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Rules for Classification and Construction I Ship Technology 1 Seagoing Ships 16 Harmony Class Rules on Rating Noise and Vibration for Comfort, Cruise Ships (v 25 kn) Edition 2003
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Page 1: Rules for Classification and Construction I Ship Technologyrules.dnvgl.com/docs/pdf/gl/maritimerules/gl_i-1-16_e.pdf · 2012-05-09 · The following Rules come into force on April

Rules for Classification and Construction I Ship Technology 1 Seagoing Ships

16 Harmony Class – Rules on Rating Noise and Vibration for Comfort, Cruise Ships (v ≤ 25 kn)

Edition 2003

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The following Rules come into force on April 1st, 2003.

"General Terms and Conditions" of the respective latest edition will be applicable (see Rules for Classification and Construction, I – Ship Technology, Part 0 – Classification and Surveys).

Reproduction by printing or photostatic means is only permissible with the consent of Germanischer Lloyd.

Germanischer Lloyd AG

Head Office Hamburg

Vorsetzen 32/35, D-20459 Hamburg

Telefon +49 40 3 61 49-0 Telefax +49 40 3 61 49-2 00

Telex 212828 glhh d [email protected] http://www.gl-group.com

Published by: Germanischer Lloyd AG, Hamburg Printed by: Gebrüder Braasch GmbH, Hamburg

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Table of Contents

Section 1 Classification

A. Scope .......................................................................................................................................... 1- 1 B. Harmony Categories (hc) ........................................................................................................... 1- 1 C. Class Notation ............................................................................................................................ 1- 1

Section 2 Required Noise and Vibration Limits

A. General ....................................................................................................................................... 2- 1 B. Noise Requirements ................................................................................................................... 2- 1 C. Vibration Requirements ............................................................................................................. 2- 1

Section 3 Required Measurements

A. General ....................................................................................................................................... 3- 1 B. Measuring Conditions ................................................................................................................ 3- 1 C. Performance of Measurements ................................................................................................... 3- 2 D. Survey Programmes ................................................................................................................... 3- 7 E. Survey Report ............................................................................................................................ 3- 7

Section 4 Calculation Procedure of hcClass_Notation

A. Determination of Single hc ........................................................................................................ 4- 1 B. Averaging of Single hc ............................................................................................................... 4- 1 C. Determination of hcClass_Notation ................................................................................................ 4- 2

Annex A Standards

A. General ....................................................................................................................................... A- 1 B. Standards .................................................................................................................................... A- 1

Annex B Definitions

A. Important Definitions ................................................................................................................. B- 1

Annex C Recommendations to Reduce Noise and Vibration

A. General ....................................................................................................................................... C- 1 B. Considerations Regarding Excitation Forces ............................................................................. C- 1 C. Theoretical Investigations .......................................................................................................... C- 1 D. Secondary Measures ................................................................................................................... C- 2 E. Supplementary Measurements during Production Phase ........................................................... C- 2

Annex D Protocol Sheet

A. Measurement Protocol Sheet ...................................................................................................... D- 1

I - Part 1 GL 2003

Table of Contents Chapter 16Page 3

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Section 1

Classification

A. Scope

1. In general, these Rules are based on national and international standards listed in Annex A. They will be adapted to the latest editions of these stan-dards when deemed necessary or will be modified to account for the progress of knowledge. The Rules reflect the state of the art in vibration and acoustic technology.

2. Some important definitions for expressions used in these Rules are given in Annex B.

3. Among various comfort-promoting factors (e.g. decor and furniture of cabins and public spaces, indoor climate, board service, ship motions etc.), two main parameters determining the comfort on board a passenger ship are dealt with in these Rules: noise and vibration.

4. In this context, noise and vibration are de-fined as follows:

– Noise: Audible air pressure variations, generated for

instance by main engines, propellers, auxiliary machinery, systems and persons within the fre-quency range of 16 to 16 000 Hz.

– Vibration: Structural oscillations in the frequency range of

1 to 80 Hz

5. The influence of ship motions (seasickness) on human wellbeing is not considered in these Rules.

6. These Rules are intended to support owners and shipyards to specify requirements regarding comfort for passengers and crew on board seagoing passenger ships.

7. Requirements according to current regula-tions of the responsible flag state regarding maximum noise and vibration levels in crew spaces have to be fulfilled independently of these Rules.

8. If the maximum speed of the passenger ship exceeds 25 knots, requirements defined for fast pas-senger vessels shall be applied. 9. If the maximum speed of the passenger ship exceeds v = 7,16 ⋅ Δ1/6 [knots], the requirements defined for high speed craft have to be applied.

10. If the length between perpendiculars is less than 120 m, limit values given in these Rules do not

apply. They shall be agreed upon separately after conferring with Germanischer Lloyd (GL).

B. Harmony Categories (hc)

To allow for a graduation of noise and vibration lev-els, 5 harmony categories hc are introduced:

hc = E = ∗∗∗∗∗ excellent comfort

hc = 1 = ∗∗∗∗ very high comfort

hc = 2 = ∗∗∗ high comfort

hc = 3 = ∗∗ moderate comfort

hc = 4 = ∗ acceptable comfort

Two separate categories, hcpass and hccrew, reflect the level attained for passenger and crew spaces, respec-tively.

1. Respective limit values of noise and vibra-tion are defined in Section 2.

2. Compliance with criteria given in these Rules shall be verified through measurements per-formed under defined conditions at specified loca-tions, see Section 3.

C. Class Notation

1. Upon request, ships complying with these Rules are granted the following special notation of Harmony Class

GL – HC (hcpass/hccrew).

For instance, HC (2/3) corresponds to a high comfort for passengers and a moderate comfort for crew, according to B.

2. For a series of ships, the required noise measurements have to be conducted individually for each ship of the series. Regarding vibration meas-urements, a reduced measurement programme can be accepted for sister ships.

3. After modifications (e.g. conversions) that might influence the noise and vibration behaviour, the class notation has to be reconfirmed by Ger-manischer Lloyd.

I - Part 1 GL 2003

Section 1 Classification Chapter 16Page 1–1

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Section 2

Required Noise and Vibration Limits

A. General

1. Requirements given in these Rules refer to human wellbeing only. However, to achieve a certain level of noise and vibration comfort, it must be ensured that main and auxiliary machinery do not vibrate heavily. Therefore, limit values given in corresponding standards or classification rules, for instance GL Rules, I – Ship Technology, Part 1 –Seagoing Ships, Chapter 2 – Machinery Installations, Section 2, Fig. 2.1, shall be observed, too.

2. Requirements regarding acoustic privacy are given in addition to those for noise and vibration.

3. Requirements for noise and vibration are presented for three operating conditions:

– Sea Mode

– Harbour Operation

– Thruster Operation

The noise and vibration limits given for Sea Mode Operation form an upper bound for any operation mode at typical ship speeds.

4. Requirements regarding measurements for three operating conditions are given in Section 3, B.

5. Limits are given separately for passenger and crew spaces.

6. Requirements are related to different immission zones as defined by Frame A, B, C and D. The principal arrangement of these zones is shown

in Fig. 2.1 for a typical seagoing passenger vessel, see also Annex B.

B. Noise Requirements

1. Most relevant standards are ISO 2923, ISO 717/1 and ISO 717/2.

2. Required noise limit values depending on the harmony category number (hc) are listed in Tables 2.1 to 2.4.

3. The measurement procedure and the calculation of the hc achieved by noise measurements are described in Section 3, C. and Section 4, respectively.

C. Vibration Requirements

1. The most relevant vibration standard is ISO 6954, edition 2000-12-15. The limit values refer, consequently, to the overall frequency-weighted rms value in the range of 1 to 80 Hz. The vibration velocities are given in mm/s.

2. Required vibration limit values depending on the harmony category (hc) are listed in Tables 2.5 and 2.6.

3. The measurement procedure and the calculation of the hc achieved by vibration measurements are described in Section 3, C. and Section 4, respectively.

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Fig. 2.1 Immission Zones

I - Part 1 GL 2003

Section 2 Required Noise and Vibration Limits Chapter 16Page 2–1

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Table 2.1 Noise Limits, Passenger Spaces

Sea Mode 1, 2 Harbour Operation 1, 2

Thruster Operation 2 , 3, 4

hc hc hc

Noise Level Limits in dB(A)

E 1 2 3 4 E 1 2 3 4 E 1 2 3 4

Indoor Spaces Aft of Frame A

First-class cabins 48 50 52 54 56 44 46 48 50 52 52 54 56 58 60

Standard cabins 52 54 56 58 60 46 48 50 52 54 56 58 60 62 64

Public spaces, type 1 and 2 56 58 60 62 64 52 54 56 58 60 60 62 64 66 68

Corridors, staircases 56 58 60 62 64 54 56 58 60 62 –– –– –– –– ––

Indoor Spaces Between Frame A and C

First-class cabins 46 48 50 52 54 44 46 48 50 52 52 54 56 58 60

Standard cabins 48 50 52 54 56 46 48 50 52 54 54 56 58 60 62

Public spaces, type 1 and 2 52 54 56 58 60 52 54 56 58 60 58 60 62 64 66

Corridors, staircases 54 56 58 60 62 54 56 58 60 62 –– –– –– –– ––

Indoor Spaces Between Frame C and D

First-class cabins 44 46 48 50 52 44 46 48 50 52 52 54 56 58 60

Standard cabins 46 48 50 52 54 46 48 50 52 54 54 56 58 60 62

Public spaces, type 1 and 2 52 54 56 58 60 52 54 56 58 60 58 60 62 64 66

Corridors, staircases 54 56 58 60 62 54 56 58 60 62 –– –– –– –– ––

Indoor Spaces Forward of Frame D

First-class cabins 44 46 48 50 52 44 46 48 50 52 52 54 56 58 60

Standard cabins 46 48 50 52 54 46 48 50 52 54 56 58 60 62 64

Public spaces, type 1 and 2 52 54 56 58 60 52 54 56 58 60 60 62 64 66 68

Corridors, staircases 54 56 58 60 62 54 56 58 60 62 –– –– –– –– ––

Outdoor Spaces

Open deck recreation areas 64 66 68 70 75 64 66 68 70 72 64 66 68 70 72

Exhaust/supply air openings in open deck recreation areas 5 68 70 72 75 80 68 70 72 75 80 68 70 72 75 80

1 In each space the noise level generated only by air-conditioning and mechanical ventilation systems must be at least 4 dB(A) below the required noise limit value for harbour operation.

2 In each sanitary cell the noise level generated only by air-conditioning exhaust air systems at full capacity must not be more than 5 dB(A) above the required noise limit value for harbour operation.

3 To be verified by measurements in the vicinity of thrusters only. Passenger indoor spaces aft of Frame A shall be considered during stern thruster operation only. All thrusters running at not less than 70 % of full load. The noise limits shall be maintained also in standby operation of thrusters.

4 Limit values valid, provided that thrusters are in operation for a maximum of 4 hours out of 24 hours. 5 At a distance of 1,5 m.

Chapter 16 Page 2–2

Section 2 Required Noise and Vibration Limits I - Part 1GL 2003

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Table 2.2 Noise Limits for Acoustic Privacy, Passenger Spaces

On board Acoustic Privacy – Sound Insulation (minimum required weighted apparent sound insulation index in dB

according to ISO 717/1 and ISO 140/4)

hc Arrangements:

E 1 2 3 4

First-class cabins to first-class cabins (incl. bath to bath) 42 40 38 36 34

First-class cabins to standard cabins (incl. bath to bath) 42 40 38 36 34

Standard cabins to standard cabins (incl. bath to bath) 40 38 36 34 32 First-class cabins to corridors 40 38 36 34 32

Standard cabins to corridors 38 36 34 32 30 Pax cabins to crew spaces 50 48 46 44 42

Pax cabins to public spaces type 11 64 62 60 58 56

Pax cabins to public spaces type 2 58 56 54 52 50 Pax cabins to staircases 2 58 56 54 52 50

Pax cabins to engine room casings, elevator casings etc. 3 60 58 56 54 52

Pax cabins to HVAC rooms 4 58 56 54 52 50

Pax cabins to engine rooms 5 64 62 60 58 56 1 The sound pressure levels (SPL) for the 1/1 octave band mid frequencies that should not be exceeded

in public spaces type 1 (when in use) are listed as follow:

Frequency in Hz 31,5 63 125 250 500 1 k 2 k 4 k 8 k

SPL in dB(A) 65 72 78 85 88 91 94 94 94

2 In general, the number of passenger cabins located adjacent to staircases have to be minimized.

3 Number of passenger cabins located adjacent to engine rooms and elevator casings etc. should be minimized. If possible, acoustic buffer zones (e.g., service stores, lockers etc.) should be arranged between cabins and casings. The average sound pressure level in engine room casings must be limited to max. 100 dB(A).

4 Average sound pressure level in HVAC rooms located adjacent to passenger cabins must be limited to max. 80 dB(A).

5 Arrangement of passenger cabins adjacent to engine rooms should be avoided. Otherwise specific provisions are required to achieve limit values.

I - Part 1 GL 2003

Section 2 Required Noise and Vibration Limits Chapter 16Page 2–3

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Table 2.2 Noise Limits for Acoustic Privacy, Passenger Spaces (cont'd.)

On board Acoustic Privacy – Impact Sound Insulation (maximum permissible normalized sound pressure level index in dB

according to ISO 717/2 and ISO 140/7)

hc Arrangements:

E 1 2 3 4

Pax cabins adjacent to pax cabins (soft floor) 46 48 50 52 54

Pax cabins adjacent to corridors (soft floor) 46 48 50 52 54 Pax cabins adjacent to crew spaces 46 48 50 52 54

Pax cabins adjacent to public spaces type 1 46 48 50 52 54 Pax cabins adjacent to public spaces type 1a maximum 46 dB Pax cabins adjacent to public spaces type 2 (hard floor) 48 50 52 54 56 Pax cabins adjacent to public spaces type 2 (soft floor) 46 48 50 52 54

Pax cabins adjacent to service spaces (galleys, pantries etc.) 46 48 50 52 54 Pax cabins adjacent to open deck recreation areas 6 maximum 60 dB

Pax cabins adjacent to jogging paths, sport courts etc. 7 7 7 7 7

6 Arrangement of passenger and crew cabins below open deck recreation areas should be avoided. However, if so arranged the limit of the normalised impact sound pressure level for cabins below those spaces must be agreed upon between owner, yard and Germanischer Lloyd but must not exceed 60 dB in any case.

7 Arrangement of passenger and crew cabins below jogging paths, sport courts etc. should be avoided. However, if so arranged the limit of the normalised impact sound pressure level for cabins adjacent to those spaces must be agreed upon between owner, yard and Germanischer Lloyd.

Chapter 16 Page 2–4

Section 2 Required Noise and Vibration Limits I - Part 1GL 2003

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Table 2.3 Noise Limits, Crew Spaces

Sea Mode 1 Harbour Operation 1

Thruster Operation 2, 3

hc hc hc

Noise Level Limits in dB(A)

E 1 2 3 4 E 1 2 3 4 E 1 2 3 4

Work Spaces

Machinery spaces (not continuously manned) 5 110 110 110 110 110 110 110 110 110 110 110 110 110 110 110

Engine control rooms 67 69 71 73 75 64 66 68 70 72 67 69 71 73 75Workshops 80 80 85 85 85 80 80 80 80 80 –– –– –– –– ––Open deck working areas 4 75 75 80 80 85 75 75 80 80 85 75 75 80 80 85Stores 5 80 80 85 90 90 75 75 80 85 85 –– –– –– –– ––Indoor spaces not specified 5 90 90 90 90 90 90 90 90 90 90 –– –– –– –– ––

Service Spaces

Galleys 6 68 70 72 75 75 66 68 70 75 75 68 70 72 75 75Serveries, pantries 6 66 68 70 75 75 66 68 70 75 75 66 68 70 75 75

Navigation Spaces

Navigation bridge and chart rooms 55 55 60 60 65 55 55 60 60 65 58 58 60 60 65Radio rooms 55 55 60 60 60 55 55 60 60 60 55 55 60 60 60Listing posts, including outdoor bridge wings 7 65 65 70 70 70 65 65 65 70 70 65 65 70 70 70

Accommodation Spaces

Day and sleeping rooms / officers 50 52 54 56 58 50 52 54 56 58 62 64 66 68 70Day and sleeping rooms / others 52 54 56 58 60 52 54 56 58 60 64 66 68 70 72Mess rooms, offices, recreation rooms 57 59 61 63 65 57 59 61 63 65 66 68 70 72 74Hospitals 54 56 58 60 60 54 56 58 60 60 64 66 68 70 72Gymnasiums, treatment rooms 57 59 61 63 65 57 59 61 63 65 –– –– –– –– ––Corridors adjacent to cabins 58 60 62 64 66 56 58 60 62 64 –– –– –– –– ––Open deck recreation areas 68 70 72 75 75 68 70 72 75 75 –– –– –– –– ––1 In each space the noise level generated only by air-conditioning and mechanical ventilation systems must be limited to at least 4 dB(A)

below the required noise limit value for harbour operation (excluding work spaces and open recreation areas). 2 To be verified by measurements in the vicinity of thrusters only. All thrusters running at not less than 70 % of full load. The noise limits

are also to be maintained in standby operation of the thrusters. 3 Limit values valid provided that thrusters are in operation for a maximum of 4 hours out of 24 hours. 4 Spaces requiring verbal communication when berthing the ship (maximum 4 hours out of 24 hours). 5 Reference is made to IMO Resolution A.468 (XII) – ear protectors should be worn when the noise level is above 85 dB(A). 6 With mechanical ventilation in normal operation. 7 Reference is made to IMO Resolution A.468 (XII) – which also requires that the noise level at ¾ speed does not exceed 68 dB in the

1/1 octave band at 250 Hz and does not exceed 63 dB in the 1/1 octave band at 500 Hz.

I - Part 1 GL 2003

Section 2 Required Noise and Vibration Limits Chapter 16Page 2–5

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Table 2.4 Noise Limits for Acoustic Privacy, Crew Spaces

On board Acoustic Privacy – Sound Insulation (minimum required weighted apparent sound insulation index in dB

according to ISO 717/1 and ISO 140/4)

hc Arrangements:

E 1 2 3 4

Cabins to cabins 40 38 36 34 32 Cabins to corridors 38 36 34 32 30 Cabins to stairways 56 54 52 50 48 Cabins to engine room casings, elevator casings etc. 1 58 56 54 52 50 Cabins to mess rooms, hospitals, gymnasiums, service spaces etc. 58 56 54 52 50 Cabins to engine rooms 2 60 58 56 54 52 1 The number of cabins located adjacent to engine rooms and elevator casings etc. should be minimized. If

possible, acoustic buffer zones (e.g., corridors, service stores, lockers etc.) should be arranged between cabins and casings. The average sound pressure level in engine room casings shall be limited to max. 100 dB(A).

2 The arrangement of cabins adjacent to engine rooms should be avoided. Otherwise specific provisions are required to achieve limit values.

On board Acoustic Privacy – Impact Sound Insulation (maximum permissible normalized sound pressure level in dB

according to ISO 717/2 and ISO 140/7)

hc Arrangements:

E 1 2 3 4

Cabins adjacent to cabins 52 54 56 58 60

Cabins adjacent to dance floors, stages etc. 50 52 54 56 58

Cabins adjacent to gymnasiums 52 54 56 58 60

Cabins adjacent to service spaces (e.g. galleys, pantries etc.) 52 54 56 58 60

Chapter 16 Page 2–6

Section 2 Required Noise and Vibration Limits I - Part 1GL 2003

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Table 2.5 Vibration Limits, Passenger Spaces

Sea Mode Harbour

Operation Thruster

Operation 1

hc hc hc

Vibration Limits in mm/s

(overall frequency weighted rms value 1 to 80 Hz)

E 1 2 3 4 E 1 2 3 4 E 1 2 3 4

Indoor Spaces Aft of Frame B

First-class cabins 1.1 1.5 1.9 2.3 2.6 –– –– –– –– –– 1.6 2.0 2.4 2.8 3.2

Standard cabins 1.6 2.0 2.4 2.8 3.2 –– –– –– –– –– 2.0 2.4 2.8 3.2 3.6

Public spaces, short exposure time 2.4 2.8 3.2 3.6 4.0 –– –– –– –– –– –– –– –– –– ––

Public spaces, long exposure time 1.8 2.2 2.6 3.0 3.4 –– –– –– –– –– –– –– –– –– ––

Corridors, staircases –– –– –– –– –– –– –– –– –– –– –– –– –– –– ––

Indoor Spaces Forward of Frame B

First-class cabins 0.8 1.2 1.6 2.0 2.4 –– –– –– –– –– 1.6 2.0 2.4 2.8 3.2

Standard cabins 1.2 1.7 2.2 2.7 3.2 –– –– –– –– –– 2.0 2.4 2.8 3.2 3.6

Public spaces, short exposure time 2.0 2.5 3.0 3.5 4.0 –– –– –– –– –– –– –– –– –– ––

Public spaces, long exposure time 1.4 1.9 2.4 2.9 3.4 –– –– –– –– –– –– –– –– –– ––

Corridors, staircases –– –– –– –– –– –– –– –– –– –– –– –– –– –– ––

Outdoor Spaces Aft of Frame B

Open deck recreation areas 2.2 2.6 3.0 3.4 3.8 –– –– –– –– –– –– –– –– –– ––

Open deck recreation areas of overhangs 2.4 2.8 3.2 3.6 4.0 –– –– –– –– –– –– –– –– –– ––

Outdoor Spaces Forward of Frame B

Open deck recreation areas 2.0 2.4 2.8 3.2 3.6 –– –– –– –– –– –– –– –– –– ––

Open deck recreation areas of overhangs 2.2 2.6 3.0 3.4 3.8 –– –– –– –– –– –– –– –– –– ––1 Thrusters operating at not less than 70 % of full load.

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Section 2 Required Noise and Vibration Limits Chapter 16Page 2–7

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Table 2.6 Vibration Limits, Crew Spaces

Sea Mode Harbour

Operation Thruster

Operation 1

hc hc hc

Vibration Level Limits in mm/s (overall frequency weighted rms

value 1 to 80 Hz) E 1 2 3 4 E 1 2 3 4 E 1 2 3 4

Work Spaces

Machinery spaces (not continuously manned) 4.4 4.8 5.2 5.6 6.0 –– –– –– –– –– –– –– –– –– ––Engine control rooms 2.4 2.8 3.2 3.6 4.0 –– –– –– –– –– –– –– –– –– ––Workshops 3.2 3.6 4.0 4.4 4.8 –– –– –– –– –– –– –– –– –– ––Stores 4.0 4.5 5.0 5.5 6.0 –– –– –– –– –– –– –– –– –– ––Indoor spaces not specified 4.0 4.5 5.0 5.5 6.0 –– –– –– –– –– –– –– –– –– ––

Service Spaces

Galleys 2.0 2.5 3.0 3.5 4.0 –– –– –– –– –– –– –– –– –– ––Serveries and pantries 2.4 2.8 3.2 3.6 4.0 –– –– –– –– –– –– –– –– –– ––

Navigation Spaces

Navigation bridges and chart rooms 2.0 2.5 3.0 3.5 4.0 –– –– –– –– –– –– –– –– –– ––Radio rooms 2.0 2.5 3.0 3.5 4.0 –– –– –– –– –– –– –– –– –– ––Listing posts including navigation bridge wings 2.8 3.2 3.6 4.0 4.4 –– –– –– –– –– –– –– –– –– ––

Accommodation Spaces

Day and sleeping rooms / officers 1.2 1.7 2.2 2.7 3.2 –– –– –– –– –– 2.0 2.5 3.0 3.5 4.0Day and sleeping rooms / others 1.6 2.0 2.4 2.8 3.2 –– –– –– –– –– –– –– –– –– ––Mess rooms, offices, recreation rooms 2.0 2.4 2.8 3.2 3.6 –– –– –– –– –– –– –– –– –– ––Hospitals 1.2 1.7 2.2 2.7 3.2 –– –– –– –– –– –– –– –– –– ––Gymnasiums, treatment rooms 2.0 2.4 2.8 3.2 3.6 –– –– –– –– –– –– –– –– –– ––Corridors adjacent to cabins –– –– –– –– –– –– –– –– –– –– –– –– –– –– ––Open deck recreation areas 2.6 3.0 3.4 3.8 4.2 –– –– –– –– –– –– –– –– –– ––1 Thrusters operating at not less than 70 % of full load

Chapter 16 Page 2–8

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Section 3

Required Measurements

A. General

1. Noise and vibration measurements and their evaluation shall be carried out by experienced techni-cians employed by a company authorized by Ger-manischer Lloyd. If desired, GL will conduct meas-urements with own experts.

2. Propulsion machinery power shall be veri-fied during measurements.

3. Measurements shall be witnessed by a GL surveyor.

B. Measuring Conditions

1. Sea mode

1.1 Propulsion machinery shall produce the necessary power to reach the service speed of the vessel as contractually agreed on. Power shall not be less than 85 % of MCR.

1.2 Controllable pitch propellers, if any, to be in normal seagoing position.

1.3 A condition with operating stabilizers to be considered.

1.4 The minimum water depth during measure-ments shall be at least five times the draught. The loading condition should be the same as specified in the contract. Deviations shall be submitted to Ger-manischer Lloyd for approval prior to trials. For ships normally operating in shallow waters, corresponding conditions have to be chosen for measurements.

1.5 Sea state 3 (significant wave height approx. 1,25 m) and a wind speed of 4 Bft should not be exceeded. For more severe weather conditions, the acceptance of measurements will be decided by GL on a case-by-case basis.

1.6 The course of the vessel shall be as straight as possible. Minimum rudder movement is impera-tive. Rudder angles shall not exceed ± 2 degrees.

1.7 The ship shall be fully outfitted, and all systems contributing to noise and vibration shall be in normal seagoing condition, i.e., all auxiliary ma-chinery, navigation instruments, radar sets etc. shall be in normal operation throughout measurements.

The communication radio shall be turned on, but not operating.

Mechanical ventilation and air-conditioning equip-ment shall be in normal operation (capacity to be in accordance with design conditions). All air-conditioning systems shall be adjusted prior to meas-urements.

1.8 Noise and vibrations caused by any unneces-sary human activity shall be avoided.

1.9 Passenger entertainment and public address systems shall be switched off.

1.10 No passengers shall be on board. Exceptions may be permitted.

1.11 Doors and windows shall, in general, be closed.

2. Harbour operation

2.1 Measurements are permissible for water depths smaller than for Sea Mode. The water depth present during harbour measurements shall be re-ported.

2.2 The presence of large noise-reflecting areas in the vicinity of the vessel shall be reported.

2.3 The influence of external noise sources, such as traffic, workshops etc., shall be reduced to a mini-mum.

2.4 All machinery, mechanical ventilation and air-conditioning equipment to be running in normal port condition, as contractually agreed on between owner and shipyard.

2.5 Requirements according to B.1.7 to 1.11 apply as well.

3. Thruster operation

3.1 Measurements shall be conducted in an open sea area. The water depth shall be reported.

3.2 Ship speed shall be close to zero.

3.3 All machinery shall be running in normal condition as necessary for Thruster Operation with not less than 70 % of full load for each thruster.

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3.4 Additional noise measurements shall be taken in selected pax and crew cabins during standby operation of thrusters.

3.5 Requirements according to B.1.5 and 1.7 to 1.11 apply as well.

C. Performance of Measurements

1. Noise

1.1 Instrumentation

1.1.1 Integrating-averaging sound level meters shall be applied. These should be able to store the measured data.

1.1.2 The instrumentation system including mi-crophone, cable and recording devices shall meet requirements for a type 1 instrument as specified in IEC 804.

1.1.3 The microphone shall be calibrated to have an essentially flat frequency response in a diffuse sound field.

1.1.4 A windscreen shall be used for outdoor measurements.

1.1.5 If a windscreen is used for indoor meas-uremts, the measured A-weighted sound pressure level shall not be influenced by more than 0,5 dB (A).

1.1.6 1/1 or 1/3 octave band filters shall comply with the requirements of IEC 1260.

1.1.7 Class 1 sound calibrators complying with the requirements of IEC 942 shall be used.

1.1.8 Calibration of measuring instrumentation:

– The compliance of the integrating-averaging sound level meter with requirements of IEC 804 shall be verified by the manufacturer or o-ther authorized organization at least every two years.

– The compliance of the sound calibrator with requirements of IEC 942 shall be verified by the manufacturer or other authorized organiza-tion at least every two years.

– The date of last verification and confirmation of compliance with relevant IEC standards shall be recorded. Calibration sheets shall be provided.

1.1.9 An instrument suitable of storing time sig-nals in case of subjectively annoying low-frequency sound (booming) or obvious tonal components shall be provided.

1.2 Number of measurement positions

1.2.1 Noise level measurements in passenger spaces

1.2.1.1 Cabins

The total number of measurement positions to be taken in pax cabins depends on the net living space of each room belonging to the individual pax cabin.

– Net living space less than or equal to 20 m2: one measurement position in the middle of the

room.

– Net living space greater than 20 m2: at least two measurement positions in the room.

On ships whose total number of passengers is less than or equal to 150, noise measurements shall be conducted in each pax cabin.

On ships whose total number of passengers is greater than 150, the number of required measurement loca-tions are defined in Table 3.1.

1.2.1.2 Public spaces of type 1 and 2

The selection of measurement positions shall be cho-sen in a way that the noise situation can be evaluated in each individual public space.

In small public spaces with an area less than or equal to 40 m², at least one measurement position shall be taken in the centre of the room.

In larger public spaces exceeding 40 m2, several mea-surement positions shall be chosen. At least one mea-surement position shall be taken for each 40 m2. It shall be ensured that the distance between any two measurement positions is not less than 2 m and not greater than 7 m. Measurement positions selected shall include positions where maximum noise levels can be expected.

1.2.1.3 Corridors

Measurement positions shall be chosen where maxi-mum noise levels can be expected (especially close to air inlets and outlets of air-conditioning systems, casings etc.). Furthermore, the maximum distance between each two measurement positions depends on the operating condition and the immission zone as follows:

– Sea Mode; aft of Frame C: 12 m

– Sea Mode; forward of Frame C: 18 m

– Harbour Operation; aft of Frame C: 18 m

– Harbour Operation; forward of Frame C: 25 m

– Thruster Operation: measurements not required.

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Table 3.1 Required Scope of Noise Measurements, Passenger and Crew Spaces (Number of Passengers > 150)

Sea Mode Harbour Operation 2

Thruster Operation 3 Verification Percentages 1

All hc All hc All hc

Indoor Spaces Aft of Frame A

Passenger first-class cabins 4 ≥ 50 ≥ 10 ≥ 20

Passenger standard cabins 4 ≥ 25 ≥ 10 ≥ 20

Crew day and sleeping rooms 4 ≥ 30 ≥ 10 ≥ 20

Crew mess and recreation rooms 4 100 ≥ 25 ≥ 50

Work spaces, control rooms, offices etc. 4 100 ≥ 25 ––

Indoor Spaces Between Frame A and C

Passenger first-class cabins ≥ 25 ≥ 10 ≥ 10

Passenger standard cabins ≥ 25 ≥ 10 ≥ 10

Crew day and sleeping rooms ≥ 30 ≥ 10 ≥ 10

Crew mess and recreation rooms 100 ≥ 25 ≥ 25

Work spaces, control rooms, offices etc. 100 ≥ 25 ––

Indoor Spaces Between Frame C and D

Passenger first-class cabins ≥ 20 ≥ 10 ≥ 10

Passenger standard cabins ≥ 20 ≥ 10 ≥ 10

Crew day and sleeping rooms ≥ 20 ≥ 10 ≥ 10

Crew mess and recreation rooms ≥ 25 ≥ 25 ≥ 25

Work spaces, control rooms, offices etc. ≥ 25 ≥ 25 ––

Indoor Spaces Forward of Frame D

Passenger first-class cabins ≥ 20 ≥ 10 ≥ 20

Passenger standard cabins ≥ 10 ≥ 10 ≥ 20

Crew day and sleeping rooms ≥ 20 ≥ 10 ≥ 20

Mess and recreation rooms ≥ 25 ≥ 25 ≥ 50

Work spaces, control rooms, offices etc. ≥ 25 ≥ 25 –– 1 For spaces not referred to in this table, C.1.2.1 and 1.2.2 applies. 2 Especially spaces in the vicinity of main noise sources (where maximum noise levels can be expected or where obviously high noise

levels are observed during the noise survey). 3 Especially spaces close to thrusters (where maximum noise levels can expected or where obviously high noise levels are observed

during the noise survey). 4 Passenger indoor spaces aft of Frame A shall be considered during stern thrusters operation only.

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1.2.1.4 Main staircases

Measurement positions shall be taken at each stair-case platform of each main staircase in Sea Mode and Harbour Operation.

1.2.1.5 Outdoor spaces

Total number of measurement positions mainly de-pend on the size of the passenger ship and on number of air-conditioning and mechanical ventilation air supply/exhaust openings located close to passenger recreation areas. In general, several measurement positions shall be taken on passengers’ open recreation deck spaces directly exposed to exhaust gas noise of the main propulsion plant and auxiliary machinery. The same applies to recreation areas located close to air sup-ply/exhaust openings of mechanical ventilation sys-tems. The final noise measurement positions on passen-gers’ open recreation deck spaces will be determined by GL.

1.2.2 Noise level measurements in crew spaces

1.2.2.1 Accommodation and work spaces

The measurement positions shall be chosen according to IMO Resolution A.486 (XII), chapter 2.8.

On ships whose total number of passengers is less than or equal to 150, noise measurements shall be conducted in each crew cabin for Sea Mode condi-tion. On ships whose total number of passengers is greater than 150, the number of noise measurements required for Sea Mode condition is given in Table 3.1. Number of measurement positions for Harbour Op-eration and Thruster Operation are given in Table 3.1, irrespective of the number of passengers.

1.2.3 Acoustic privacy measurements

1.2.3.1 Sound insulation

Measurements shall be conducted according to ISO 717/1 and ISO 140/4 in crew and passenger spaces. Measurements shall be conducted in at least two cabins of each type.

1.2.3.2 Impact sound insulation

Measurements shall be conducted according to ISO 717/2 and ISO 140/7 in crew and passenger spaces. Measurements shall be conducted at least in two cabins located close to relevant spaces for each com-bination of cabin type and floor construction.

1.3 Measurement procedure

1.3.1 General

1.3.1.1 The most relevant standards to be observed are:

– ISO 2923 – ISO 140 – ISO 717 – E DIN 45681

1.3.1.2 A maximum of three persons are allowed to stay in the same indoor space/cabin when the noise measurements are being conducted.

1.3.1.3 The equivalent continuous A-weighted sound pressure level in dB(A) shall be measured. The corresponding band levels of the 1/1 octave band mid frequencies of at least 31,5 Hz to 8 000 Hz shall be measured simultaneously. After each measurement, all measured data shall be stored on the hard disk of the sound level meter.

1.3.1.4 The calibration of the measuring instruments shall be checked immediately before and after each period of use. The calibration level shall be measured and stored after each calibration.

1.3.1.5 Overall sound pressure level in dB(A), file number of the data storage (ID number), measure-ment location, noise limit according to hc target and subjective noise impression shall be recorded and immediately noted in measurement protocol sheets after recording, see Annex D.

1.3.1.6 The sound level instrumentation shall be set to "fast" response. The measuring time shall be at least 15 seconds if the fluctuation of the overall sound pressure level is equal to or less than ± 3 dB(A). If fluctuations exceed ± 3 dB(A) or if the sound is cyclic or irregular, the instrument setting shall be changed to "slow" response and the measur-ing time shall be extended to at least 30 seconds.

1.3.1.7 During each measurement, the microphone shall slowly be moved horizontally and/or vertically over a distance of approximately ± 0,5 m.

1.3.1.8 In spaces such as radio and radar rooms, care should be taken to ensure that any electrical interference present does not give rise to a false indi-cation of the noise level.

1.3.1.9 A microphone windscreen shall be used when measuring noise levels on open deck spaces and also below decks where there is any substantial air movement. When used for indoor spaces, C.1.1.5 has to be observed.

1.3.1.10 Wind noise, e.g. wind trash, singing or simi-lar effects has to be reported for surveyed outdoor spaces.

1.3.1.11 For measurements in passenger spaces, it is recommended to position the microphone at an aver-age height of approx. 1,4 m to cover both the position of a sitting and a standing person.

1.3.1.12 The microphone position should not be closer than 0,5 m to boundary surfaces, e.g. lining walls, ceilings, windows, floors and bulkheads.

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1.3.2 Acoustic privacy

1.3.2.1 Measurements shall be conducted according to ISO 717-1, ISO 717-2, ISO 140/4 and ISO 140/7.

1.3.2.2 For sound transmission measurements be-tween corridor and cabin, the microphone position in the cabin (receiver room) shall be located where passengers normally stay.

1.3.3 Presence of secondary noise sources

In general, secondary noise sources (e.g. rattling, knocking and squeaking noises from doors, panels, furniture, fittings or fixtures etc.) shall be eliminated in crew and passenger accommodation spaces.

1.3.4 Presence of obvious tonal components

1.3.4.1 In general, obvious tonal components in passenger and crew spaces will not be accepted for any of the conditions: Sea Mode, Harbour Operation and Thruster Operation.

1.3.4.2 Obvious tonal components audible in pax cabins and/or in passenger public spaces and/or in crew accommodation spaces shall be reported, see Annex D.

1.3.4.3 The tone rating procedure, as mentioned in Annex B, shall be applied in passenger spaces where steady noise with audible discrete tones is present. In general, the application of this tone rating procedure does not depend on the hc target, but will be handled in a stricter manner for ships with a hc target E, 1 and 2.

1.3.4.4 This procedure shall also be applied in crew accommodation spaces on board ships with an hc target of E, 1 and 2. For ships with an hc target 3 or 4, IMO Resolution A.468 (XII) shall be applied.

1.3.5 Presence of booming effects

1.3.5.1 In general, the presence of annoying low-frequency sound (booming effects) occurring in pas-senger and crew spaces during Sea Mode, Harbour Operation and Thruster Operation will not be ac-cepted.

1.3.5.2 Annoying low-frequency sound audible in pax cabins and/or in passenger public spaces and/or in crew accommodation spaces shall be reported, see Annex D.

1.3.5.3 When booming effects are present in pas-senger spaces, the booming rating procedure as men-tioned in Annex B shall be applied, irrespective of the hc target chosen for the ship.

1.3.5.3.1 The procedure as described in IMO Reso-lution A.468 (XII) shall be applied in crew accom-modation spaces and does not depend on the hc target chosen for the ship.

1.3.6 Presence of impulse noise

1.3.6.1 In general, impulse noise in passenger and crew spaces will not be accepted for any of the condi-tions: Sea Mode, Harbour Operation and Thruster Operation.

1.3.6.2 The presence of impulse noise shall be de-termined according to the definition as given in Annex B.

2. Vibration

2.1 Instrumentation

2.1.1 The equipment shall be calibrated at periodic intervals of not more than two years. Calibration sheets shall be provided.

2.1.2 On non-magnetic floors, measuring sensors should preferably be mounted on a three-legged plate with a minimum weight of 1500 g.

2.1.3 The instrumentation shall allow for calcula-tion of the weighted rms value in terms of vibration velocity according to ISO 6954.

2.1.4 Provision shall be made for the storage of all spectra and a limited number of time records.

2.1.5 The instrumentation shall comply with re-quirements of ISO 8041.

2.2 Number of measurement positions

2.2.1 The required number of measurement posi-tions depends on the vibration direction to be meas-ured (longitudinal, transverse or vertical).

2.2.2 Measurement positions for assessing longi-tudinal vibrations shall be chosen in a way that meas-urement results adequately reflect the global level. At least one measurement position should be chosen at the inner bottom, the strength (weather) deck and the top deck level.

2.2.3 Measurement positions for assessing trans-verse vibrations shall be chosen in a way that results adequately reflect the global level. Measurement positions should be located at the strength (weather) deck of the vessel and at the highest deck of ship. The longitudinal distance of measurement positions shall not exceed Lpp/4.

2.2.4 The scope of measurements in vertical direc-tion for passenger and crew accommodation areas, expressed in verification percentages, is listed in Table 3.2.

2.2.5 In rooms/spaces of a more unique character, e.g. public spaces, open deck recreation areas, of-fices, mess rooms etc., the vertical vibration level shall be measured individually for each room/space.

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Normally, measurements will be carried out in the centre of the room.

2.2.6 For rooms/spaces with an area exceeding 40 m2, several measurement positions shall be chosen (at least one position per 40 m2) in a way that subjec-tively high vibrations in vertical direction are cov-ered. 2.3 Measureme nt procedure

2.3.1 The relevant standards are ISO 4867 and 4868.

2.3.2 The velocity spectrum, achieved by an FFT analysis of the measured time series, shall generally be made available, i.e. during sea trials. The spectrum shall be stored.

2.3.3 If desired by GL experts, for instance if beating occurs, time records of selected measurement positions shall be recorded and stored.

2.3.4 To ensure comparability of the spectra, the following parameters shall be applied for data acqui-sition and signal processing:

– Measurement time per point: ≥ 1 min

– Sampling rate: ≥ 300 1/s

– Spectral frequency range: 1 Hz to 80 Hz

– Minimum spectral resolution: 0,2 Hz

– FFT window function: flat top (if not available, Hanning window)

– FFT averaging mode: linear averaging (stable mean)

2.3.5 The results shall be presented as weighted rms values in terms of vibration velocity.

Table 3.2 Required Scope of Vibration Measurements, Passenger and Crew Spaces, Vertical Direction

Verification Percentages 1 Sea Mode

Harbour Operation

Thruster Operation

Aft of Frame B

Passenger first-class cabins ≥ 50 –– ≥ 30 2

Passenger standard cabins ≥ 30 –– ≥ 30 2

Crew day and sleeping rooms ≥ 30 –– ≥ 30 2

Spaces Between Frame B and D

Passenger first-class cabins ≥ 20 –– ––

Passenger standard cabins ≥ 10 –– ––

Crew day and sleeping rooms ≥ 10 –– ––

Spaces Forward of Frame D

Passenger first-class cabins ≥ 20 –– ≥ 30

Passenger standard cabins ≥ 10 –– ≥ 30

Crew day and sleeping rooms ≥ 10 –– ≥ 30 1 For spaces not referred to in this table, C.2.2.5 and 2.2.6 applies. 2 For vessels equipped with stern thruster only.

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D. Survey Programmes

1. General

Different types of measurements which are to be conducted on board shall be described in six individ-ual Survey Programmes:

Noise VibrationPart I: Sea Mode

Part II: Harbour Operation

Part III: Thruster Operation

Part IV: Acoustic Privacy

Part V: Sea Mode

Part VI: Thruster Operation

At least three months prior to measurements the cor-responding Survey Programmes should be submitted to GL for approval.

All Survey Programmes shall be based on the final design stage of the ship and shall be presented in form of an A4-sized document with numbered pages. The use of A3 format is restricted to drawings. Moreover, programmes are meant to give the persons performing measurements necessary background information for a straightforward execution of meas-urements.

2. Data and drawings

2.1 Following items form the standard informa-tion required for approval of the Survey Programmes; additional documents can be required if deemed nec-essary.

2.2 General arrangement drawings of the ship (preferred scale 1:50, 1:100, 1:250 or 1:500).

2.3 Machinery arrangement drawings, including casing arrangement and machinery legend (preferred scale 1:100, 1:250 or 1:500).

2.4 Drawing for thermal, fire and sound protec-tion, including insulation details (e.g. sketches, mate-rial properties etc.).

2.5 Floor and deck covering drawings (thermal, fire and sound protection), including insulation de-tails (e.g. sketches, material and acoustical properties etc.) .

2.6 General arrangement drawings of mechani-cal ventilation systems, including location of HVAC rooms. All relevant structure-borne and airborne noise sources shall be indicated in the drawings (in-cluding the air supply / exhaust openings of mechani-cal ventilation and HVAC systems).

2.7 Data and drawings required according to ISO 717-1 and ISO 717-2.

2.8 Acoustic privacy plan (see Annex B).

2.9 Detailed description (sketches, material properties etc.) of noise abatement measures which are provided in cabins adjacent to machinery spaces, casings, trunks etc.

3. Content of each Survey Programme

3.1 Target hcpass and hccrew

3.2 Ship particulars

3.3 Main data of propulsion plant, propeller, auxiliary engines.

3.4 Environmental conditions expected during measurements.

3.5 Permissible range of wind speed, sea state and water depth.

3.6 Operating conditions expected during meas-urements.

Loading condition, displacement, draughts, power and speed of main engine, propeller and auxiliary machinery.

3.7 Measurement instrumentation

3.8 Prepared measurement protocol sheets and sketches for each immission zone.

Table indicating for each measurement position: number, location (frame, transverse offset from CL, deck level), measurement direction, kind and area [m²] of space/room and limit values corresponding to hc target.

Measurement positions plotted in general arrange-ment plans indicating number, position and direction to be measured.

E. Survey Report

A Survey Report contains all results of each meas-urement on board, executed on the basis of the Sur-vey Programmes.

Each Survey Report shall contain the following do-cumentation:

1. Ship and machinery data

2. Loading condition

3. Any deviation from the Survey Programmes, e.g. environmental and operation condition, meas-urement locations, number, instrumentation etc.

4. Wind speed and direction, sea state (esti-mated wave height and direction), ship course and speed

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5. Filled-in measurement protocol sheets for noise and vibration.

6. Calculation of overall hc achieved on the basis of measurement results.

7. All measured 1/1 and/or 1/3 octave band noise levels shall be submitted (CD, discettes or via e-mail).

8. All measured vibration spectra shall be sub-mitted (CD, discettes or via e-mail). The same applies to selected time series if desired by GL surveyor.

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Section 4

Calculation Procedure of hcClass_Notation

A. Determination of Single hc

The measured overall values for each individual measuring location during the acceptance tests (see Section 3) are transformed to the corresponding sin-gle hc on the basis of the limits given in Section 2.

The measurement values must not be rounded, i.e.:

– A measured noise level of 46,1 dB(A) exceeds a given limit of 46 dB(A),

– A measured vibration level of 3,21 mm/s exceeds a given limit of 3,2 mm/s.

B. Averaging of Single hc

All hc have to be determined separately for passenger and crew spaces.

When averaging, for the hc 'E' the value '0' must be used.

For hcClass_Notation E, 1 and 2 the single hc must not exceed the desired hcClass_Notation by more than 2 cate-gories.

For hcClass_Notation 3 and 4 the measured noise and vibration levels must not exceed the respective limit values by more than 2 dB or 1,0 mm/s.

If the single hc is smaller than the desired hcClass_Notation, the latter must be used for the average hc calculation.

For vibration only: In a room/space with several measurement positions, the tar-get hc shall not be exceeded at more than one position.

1. Noise

1.1 The hcSPL_Cabins is defined as the arithmetic mean value (average hc) of all single hc determined during the required acceptance trials for the sound pressure level in passenger and crew cabins, accord-ing to the following ranges:

hcSPL_Cabins = E for average hc = 0,00 to 0,25

hcSPL_Cabins = 1 for average hc = 1,00 to 1,25

hcSPL_Cabins = 2 for average hc = 2,00 to 2,25

hcSPL_Cabins = 3 for average hc = 3,00 to 3,25

hcSPL_Cabins = 4 for average hc = 4,00

1.2 The hcSPL_Others is defined as the arithmetic mean value (average hc) of all single hc determined during the required acceptance trials for the sound pressure level in passenger and crew spaces other than cabins, according to the following tolerances:

hcSPL_Others = E for average hc = 0,00 to 0,35

hcSPL_Others = 1 for average hc = 1,00 to 1,35

hcSPL_Others = 2 for average hc = 2,00 to 2,35

hcSPL_Others = 3 for average hc = 3,00 to 3,35

hcSPL_Others = 4 for average hc = 4,00

1.3 The hcAcousticPrivacy is defined as the arithmetic mean value (average hc) of all single hc determined during the required acceptance trials for the sound and impact sound insulation, according to the follow-ing tolerances:

hcAcousticPrivacy = E for average hc = 0,00 to 0,35

hcAcousticPrivacy = 1 for average hc = 1,00 to 1,35

hcAcousticPrivacy = 2 for average hc = 2,00 to 2,35

hcAcousticPrivacy = 3 for average hc = 3,00 to 3,35

hcAcousticPrivacy = 4 for average hc = 4,00

2. Vibration

2.1 The hcLongVib corresponds to the worst sin-gle hc determined by measurements of the longitudi-nal vibrations during the required acceptance trials.

2.2 The hcTransvVib corresponds to the worst sin-gle hc determined by measurements of the transverse vibrations during the required acceptance trials.

2.3 The hcVertVib is defined as the arithmetic mean value (average hc) of all single hc determined by measurements of the vertical vibrations during the required acceptance trials, according to the following tolerances:

hcVertVib = E for average hc = 0,00 to 0,10

hcVertVib = 1 for average hc = 1,00 to 1,10

hcVertVib = 2 for average hc = 2,00 to 2,10

hcVertVib = 3 for average hc = 3,00 to 3,10

hcVertVib = 4 for average hc = 4,00 to 4,10

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C. Determination of hcClass_Notation

The hcClass_Notation is determined separately for passen-ger and crew spaces.

The hcClass_Notation is the worst hc out of the following six hc, taking the three types of conditions into ac-count (Sea Mode, Harbour Operation and Thruster Operation):

Noise: hcSPL_Cabins

hcSPL_Others

hcAcoustic_Privacy

Vibration: hcLong_Vib

hcTransv_Vib

hcVert_Vib

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Annex A

Standards

A. General

1. If these Rules contain procedures deviating from the relevant standards, these Rules shall have priority.

B. Standards

1. Noise standards

– IMO Resolution A.468 (XII): 1982, "Code on noise levels on board ship"

– IMO Resolution A.343 (IX): 1975-11, "Rec-ommendation on Methods of Measuring Noise Levels at Listening Posts"

– ISO 2923, 1996-12, "Acoustics – Measurement of noise on board vessels"

– ISO 31-7: 1992-09, "Quantities and units of acoustics"

– IEC 651: 2001-10, Ed. 1.2, "Sound level me-tres"

– IEC 1260: 1995-08 and IEC 1260-am1: 2001-09, Electroacoustics - Octave-band and frac-tional-octave-band filters"

– IEC Publication 804, and amendment no. 1, 1989, "Integrating/averaging sound level me-ters"

– IEC 942: 1997-11, Ed. 2.0 and IEC 942-am1: 200-10, Ed. 2.0 "Sound calibrators"

– ISO 717/1: 1996-12, "Acoustics – Rating of sound insulation in buildings and of building elements – Part 1: Airborne sound insulation in buildings and interior elements"

– ISO 717/2: 1996-12, "Acoustics – Rating of sound insulation in buildings and of building elements – Part 2: Impact sound insulation"

– ISO 140/4: 1998-12, "Acoustics – Measure-ment of sound insulation in buildings and of building elements – Part 4: Field measurements of airborne sound insulation between rooms"

– ISO 140/7: 1998-12, "Acoustics – Measure-ment of sound insulation in buildings and of building elements – Part 7: Field measurements of impact sound insulation of floors"

– ISO 1999: 1990-01, "Acoustics – Determina-tion of occupational noise exposure and estima-tion of noise-induced hearing impairment"

– E DIN 45681: 1992-01, "Bestimmung der Ton-haltigkeit von Geräuschen und Ermittlung eines Tonzuschlages für die Beurteilung von Ge-räuschimmissionen" ("Detection of tonal com-ponents of noise and determination of a tone adjustment for the assessment of noise immis-sion")

2. Vibration standards

– ISO 6954: 2000E, "Mechanical vibration – Guidelines for the measurement, reporting and evaluation of vibration with regard to habitabil-ity on passenger and merchant ships"

– ISO 2631-1: 1997 (E), "Mechanical vibration and shock – Evaluation of human exposure to whole-body vibration – Part 1: General re-quirements"

– ISO 2631-2: 1989 (E), "Mechanical vibration and shock – Evaluation of human exposure to whole – body vibration – Part 2: Continuous and shock induced vibration in buildings (1 - 80 Hz)"

– ISO 4867: 1984 (E), "Code for the measure-ment and reporting of shipboard vibration data"

– ISO 4868: 1984 (E), "Code for the measure-ment and reporting of local vibration data of ship structures and equipment"

– ISO 8041: 1990 (E), "Human response to vibra-tion – Measuring instrumentation"

– Germanischer Lloyd, Ed. 2000, "Rules for Classification and Construction, I – Ship Tech-nology, Part 1 –Seagoing Ships, Chapter 2 – Machinery Installations"

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Annex B

Definitions

A. Important Definitions

– Angular frequency, circular frequency:

ω [rad/s] is the product of the frequency of a sinusoidal quantity and the factor 2 π:

ω = 2π ⋅ f

– Acoustic privacy: "Privacy" from an acoustical point of view, i.e.

the state of being alone and relatively undis-turbed with regard to noise emissions from neighbouring cabins, sanitary cells, corridors, public spaces, open deck recreation spaces, service spaces etc. (sound and impact sound in-sulation).

– Acoustic privacy plan: Drawings showing the arrangement of all cabin

types including noise limit values to be kept. See also "cabin type".

– Auxiliary machinery: Machinery, other than main propulsion ma-

chinery, operating when the ship is in normal service, e.g. auxiliary diesel engines, turbo-generators, hydraulic motors and pumps, com-pressors, boilers, ventilation fans, gears, pumps.

– Abatement measures: Noise and/or vibration control measures, e.g.

with the aim of reducing the airborne and/or structure-borne noise emission as well as of vi-bration levels of structures, equipment etc.

– A-weighted sound pressure level LAeq or LAeq,T:

The A-weighted equivalent continuous sound pressure level using the frequency weighting "A" as specified in the IEC publication 60651 within a measurement time interval T.

– Beat, beating: Periodic amplitude variations of an oscillation

resulting from the superposition of two excita-tion sources of slightly different frequencies. Beating which occurs in the audible frequency range is experienced as being annoying.

– Boom, booming: Deep, hollow resonant low-frequency sound in

the range between 16 and 125 Hz. Booming is mainly due to one or more discrete tonal com-ponents of significantly greater amplitudes than

those of the adjacent spectrum level. Booming is experienced as being annoying and can only be detected subjectively. See also "steady noise with audible discrete tones".

– Booming rating procedure: Procedure for measuring and assessing the

occurrence of audible discrete tones below 125 Hz (booming effect). The procedure devel-oped by Germanischer Lloyd is based on ex-perimental investigations on board ships.

As result of this procedure a booming adjust-ment (CB in dB(A)) is established. The noise rating level has to be used for further evalua-tion.

– Bathroom: A room in which there is, e.g. a shower and/or

a bathtub, a washbasin, a toilet etc. In these Rules, the area of a bathroom is greater than 6 m2.

– Cabin type: Cabins with different types of interior systems

(lining walls, ceilings, doors, etc.), floor con-structions, floor coverings etc. See also "Acoustic Privacy Plan".

– Crew spaces: Cabins, offices (for carrying out the ship's

business), hospitals, mess rooms, recreation rooms (such as lounges, smoke rooms, cine-mas, libraries, hobby and game rooms) and open recreation areas used by officers, hotel staff and crew.

– Corridors: Passageways/alleyways arranged in crew and

passenger spaces.

– Displacement (Δ): Displacement of the vessel in metric tonnes.

– Dressing-room: A room for putting on clothes and a place

where clothes are stored, usually in a built-in wardrobe. In these Rules, the area of a dressing room is greater than 8 m2. Otherwise the dress-ing room is not to be defined as a "room".

– Driving–point impedance: In a mathematical sense, the complex ratio of

force to velocity taken at the same point in a

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mechanical system during simple harmonic motion.

– Engine or shaft speed: Number of revolutions per minute [rpm]

– Equivalent continuous sound pressure level Leq or Leq,T :

Unweighted sound pressure level of a continu-ous steady sound. Within a measurement time interval T this sound has the same mean square sound pressure as a sound under consideration that varies with time. It is expressed in decibels by the following equation:

( )

( ) 2t2eq eq T 10

2 1 ot1

p t1L L , 10 log dtt t p

⎡ ⎤⎛ ⎞⎢ ⎥= = ⋅∫ ⎜ ⎟⎢ ⎥− ⎝ ⎠⎣ ⎦

where: (t2 – t1) = is the period T over which the aver-

age is taken, starting at t1 and end-ing at t2

p (t) = unweighted instantaneous rms sound pressure between 16 and 16 000 Hz

p0 = 2 ⋅ 10–5 Pa (reference level)

– Exposure time (vibration): A distinction is made as to whether the rooms

or spaces are characterized by "short" or "long" exposure times. Typical rooms/spaces with short exposure times are receptions, shops, al-leyways, staircases, lobbies, sanitary rooms etc. Typical rooms/spaces with long exposure times are restaurants, cafeterias, bars, theatres, cine-mas, lounges, conference rooms, hospitals, dis-cos etc.

– Fluctuating noise: The measured sound pressure level (e.g. pointer

of the display) varies more than ± 3 decibels with the "slow" meter characteristic switched on. Impulse noise must be excluded.

– Frame A, B, C, D: See "immission zones"

– Hard floor: Floor characterized by a relatively "hard" final

covering, e.g. uncovered steel deck, wood, tiles, marble, PVC etc. fitted on top of floating floors, viscoelastic floors, normal deck compo-nents, steel decks etc.

– Hotel staff spaces: See "crew spaces"

– HVAC: Heating, venting and air-conditioning system

– Immission zones:

Typical noise and vibration immission zones are defined as follows:

– Frame A:

A virtual frame section at a maximum distance of 3 times the propeller diameter in front of the propeller plane.

– Frame B:

A virtual frame section or the aft main vertical fire zone bulkhead a distance of at least 0,15 Lpp in front of the propeller plane.

– Frame C:

Forward bulkhead of forward engine room (main or auxiliary diesel engine room).

– Frame D:

20 m aft of rear bulkhead of bow thruster room.

– Impedance:

See "driving-point impedance"

– Impulse noise:

Noise of less than one second duration that occurs as an isolated event or as one of a series of events with a repetition rate of less than 15 times per second. The presence of impulse noise shall be determined by obtaining the dif-ference between the equivalent continuous sound pressure level measured with time weighting "impulse" and "fast". If the differ-ence is more than 2 dB, the presence of impulse noise may be assumed.

– Impulse rating procedure:

Procedure for measuring and assessing the occurrence of impulse noise events. As result of this GL procedure an impulse adjustment (CI in dB(A)) is established. The noise rating level has to be used for further evaluation.

– Integrating sound level meter:

A sound level meter designed or adapted to measure the level of the mean squared time av-eraged A-weighted sound pressure level (IEC 804).

– ISO noise rating (NR) number:

The number found by plotting the 1/1 octave band spectrum of the NR curves given in ISO Standard R 1996-1967 and selecting the highest noise rating curve tangent to the spectrum .

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– Machinery spaces: All spaces containing propulsion machinery,

boilers, steam and internal combustion engines, generators and major electrical machinery, oil filling stations, refrigerating, stabilizing, hy-draulic units, air-conditioning cooling com-pressors, etc.

– Maximum continuous rating (MCR): Designed maximum continuous power rating of

main engines.

– Measured SPL: The sound pressure level measured with a

sound level meter or sound measurement in-strumentation. The measured SPL shall be ex-pressed to one decimal place.

– Net living space: Total living area of an individual pax cabin

without sanitary cell and balcony in square me-tres.

– Noise level: See "A-weighted sound pressure level".

– NRC: Noise rating curve, see "ISO noise rating (NR)

number".

– Noise rating level: The noise rating level LA, r is defined as fol-

lows:

A, r Aeq T I BL L C C C= + + + in dB(A)

LA, r is the noise rating level in dB(A)

LAeq is the measured overall A-weighted sound pressure level

CT, CI, CB are adjustments as result of the tone, impulse and booming rating procedure

– NoiseFEM: The Noise Finite Element Method (NoiseFEM)

developed by Germanischer Lloyd makes it possible to predict the propagation of structure-borne noise energy in complex ship structures. For this purpose the NoiseFEM uses the ge-ometry and material data of existing global fi-nite element models created mainly for strength and vibration computations. NoiseFEM is based on principles also used in SEA. For de-tailed information see:

C. Cabos and H. G. Matthies:

"A method for the prediction of structure-borne noise propagation in ships", Proceed-

ings of the 6th international congress on sound and vibration 1999, Technical Univer-sity of Denmark

– Normal service speed: Shaft speed and propulsion power correspond-

ing to service speed contractually agreed on, at least at 85 % MCR.

– Officers’ spaces: See "crew spaces".

– Overall frequency-weighted rms value: The overall frequency-weighted rms value has

to be determined according to ISO 6954, sec-ond edition 2000-12-15.

– Overhang: An overhang in this context is the part of a

deck area protruding the vertical support (walls, pillars).

– Passenger: Any person on board other than members of the

crew or persons employed or engaged in any capacity for the business of that ship.

– Pax cabins: All types of cabins (e.g. suite, first-class, stan-

dard cabin etc.) intended to be used by passen-gers.

– Passenger indoor spaces: All areas used by passengers in enclosed spaces

of the vessel.

– Passenger outdoor spaces: All outdoor recreation areas to where passenger

access is foreseen.

– Public spaces, type 1: Enclosed spaces for passenger recreation where

the noise level normally is or may be high when in use, e.g. entertainment spaces such as discos, theatres, cinemas, gymnasiums, etc.

– Public spaces, type 1a: Separated deck/floor spaces of public spaces

type 1 such as dance floors, stages and gymna-sium floors.

– Public spaces, type 2: Enclosed spaces for passenger recreation where

the noise level is not normally high (approx. 75 dB(A)) or can be expected to be low (approx. 65 dB(A)) when in use, e.g. confer-ence rooms, casinos, restaurants, bars, shops, atriums, galleries, receptions, observation lounges, libraries etc.

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– RMS value:

The rms value of a single-valued function, f(t), over an interval between t1 and t2 is

( )

1 2t2 2t1

2 1

f t dtrms value

t t

⎡ ⎤∫⎢ ⎥

= ⎢ ⎥−⎢ ⎥

⎢ ⎥⎣ ⎦

– Room space: Total room area of an individual public space

in square metres.

– SEA: Statistical Energy Analysis. For detailed infor-

mation see:

R. H. Lyon and R. G. DeJong, "Theory and Applications of Statistical En-

ergy Analysis", Butterworth Heinemann, Boston 1995

– Soft floor: Floor characterized by a relatively soft final

covering, e.g. carpets, carpeting etc., fitted on top of floating floors, viscoelastic floors, nor-mal deck compounds, steel decks etc.

– Sound pressure level "L": A measure of sound level on logarithmic scale

given by:

[ ]100

pL 20 log dBp

⎛ ⎞= ⎜ ⎟

⎝ ⎠

where: p = rms value of measured sound pressure

between 16 and 16 000 Hz p0 = 2 ⋅ 10–5 Pa reference level

– Steady noise without audible discrete tones: Level fluctuations equal to or less than ± 3

decibels. This type of noise is frequently re-ferred to as "broad-band" noise. Obvious tonal components of noise (tonality and/or booming) in the whole audible frequency range between

16 and 16 000 Hz are absent or negligibly small.

– Steady noise with audible discrete tones: This type of noise has components at one or

more discrete frequencies having significantly greater amplitudes than those of the adjacent spectrum level. Audible discrete tonal compo-nents of noise (tonality and/or booming) can occur in the whole audible frequency range be-tween 16 and 16 000 Hz.

– Sanitary cell: A space in which there is, e.g. a shower and/or

bathtub, a washbasin, a toilet etc. In these Rules, the room space of a sanitary cell is less than or equal to 6 m2. Sanitary cells are not de-fined as "rooms".

– Suite: First-class passenger cabin/space with a set of

at least two adjacent rooms, e.g. bedroom, liv-ing room and/or sitting room, bathroom, dress-ing room etc.

– Tonality, annoying discrete tone: A sound wave whose instantaneous sound

pressure varies essentially as a simple sinusoi-dal function of time (pure tone). Tonality is ex-perienced as being annoying and can only be detected subjectively. Tonality is defined in the frequency range between 125 and 16 000 Hz. It is mainly caused by main reduction gears, pumps, air-conditioning cooling compressor units, thruster gears, HVAC inlet and outlet openings etc.

– Tone rating procedure: Procedure for measuring and evaluating the

occurrence of tonality. It was developed by Germanischer Lloyd on the basis of national standards and experimental investigations on board ships.

As a result of this procedure, a tone adjustment (CT in dB(A)) is established. The noise rating level has to be used for further evaluation.

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Annex C

Recommendations to Reduce Noise and Vibration

A. General

1. To maintain the required noise and vibration levels various investigations and noise and vibration reduction measures are recommended. This is true for the planning, design, fabrication and testing phase of a newbuilding.

B. Considerations Regarding Excitation Forces

By nature, the reduction of noise and vibration exci-tation forces is the most effective way to reduce the noise and vibration levels. Therefore it is recom-mended:

– to optimise the ship's lines by model tests in order to achieve an appropriate wake distribu-tion

– to optimise the propeller design with regard to noise and vibration excitation by cavitation tank tests

– to take into account the noise and vibration excitation characteristics of main and auxiliary machinery, gear, bow thruster etc. by appropri-ate choice of suppliers

C. Theoretical Investigations

1. Noise and vibration aspects should be con-sidered as early as possible in the design process.

2. The extent of the theoretical investigations necessary depends on the experience of the yard with the relevant ship type and the hc which shall be achieved. As a guideline the analyses summarised in Table C.1. are recommended.

The following types of investigations are distin-guished:

Review of General Arrangement Plan Prior to detailed investigations, the general arrange-ment plan is reviewed with regard to noise and vibra-tion.

Local Vibration Calculation Natural frequencies of plate fields, stiffeners and small regularly stiffened panels are estimated by means of empirical formulas. The objective is to avoid resonance with main excitation frequencies. Added masses as well as hydrodynamic masses have to be considered. Attention should especially focus on local structures in the vicinity of excitation sources (e.g. main propulsion, bow and stern thrust-ers) as well as on structural components of public, living and working spaces. Natural frequencies of all structural components shall be chosen to have a suffi-cient margin to main excitation frequencies.

Noise Prediction A noise prediction is conducted at an early design stage. Semi-empirical noise prediction programmes are applied to predict the average airborne noise levels. Noise limits specified for passenger and crew spaces are compared with predicted values.

Global Vibration Level Prediction

In a global vibration level prediction, the vibration level at "global" points of the ship structure is esti-mated on the basis of a forced vibration calculation in the lower frequency range (~ 1 Hz to 20 Hz). Dy-namic magnification due to local resonances of plate fields, stiffeners or panels is not considered. These local structural systems are investigated separately (see "Local Vibration Calculation").

The vibration level is estimated for relevant loading conditions at representative points of the ship struc-ture.

If the expected vibration level exceeds specified limits, modifications of the steel structure, a different number of propeller blades, arrangement of compen-sators, etc. are proposed as possible means of im-provement.

Detailed Vibration Level Prediction A detailed vibration level prediction represents an extension of a global vibration level prediction, i.e., the dynamic magnification due to vibrations of large deck panel structures is considered. The distribution of homogeneous and inhomogeneous masses on decks are taken into account as realistically as possi-ble. Detailed Impedance Investigation

Driving-point impedance levels (frequency range approx. 50 to 300 Hz) of machinery foundations, shell constructions above the propeller and of other critical areas are determined by means of detailed

local finite element models as early as possible dur-ing the design stage. The aim of such an investigation is to optimize relevant parts of the ship structure from an acoustical point of view.

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NoiseFEM Analysis / Statistical Energy Analysis (SEA) With an SEA or a NoiseFEM analysis, the sound propagation within the structure is predicted. Consid-ering the main structural members, the structure-borne noise intensity flow is calculated for each sub-system of the SEA/NoiseFEM model. Then the en-ergy level within each subsystem is used for predict-ing average structure-borne and airborne noise levels in the ship.

D. Secondary Measures

1. If the theoretical investigations reveal that the required noise and vibration levels probably can not be maintained secondary measures should be foreseen, i.e. – Isolation (resilient supports for instance) – Insulation, Encapsulation – Damping (floating floors for instance) – Compensation of vibration excitation forces

– Silencing – Structural modifications

E. Supplementary Measurements during Production Phase

1. It is recommended to carry out test bed noise and vibration measurements for machinery compo-nents in order to check the adherence to noise and vibration specifications agreed on with suppliers.

2. During outfitting stage the local vibrations of deck structures should be measured (impact or/and exciter measurements) to verify calculation results and to identify and rectify local structural deficien-cies.

3. During outfitting stage the impedance of machinery foundations should be measured to verify calculation results and to identify and rectify local structural deficiencies.

Table C.1 Recommended Theoretical Investigations for Seagoing Passenger Ships (v ≤ 25 knots)

Seagoing Passenger Ships

hc

Type of Investigation

E 1 2 3 4

Review of General Arrangement 1

Local Vibration Calculation

Noise Prediction 1

Global Vibration Level Prediction

Detailed Vibration Level Prediction

Detailed Impedance Investigation

Detailed Noise Analysis (e.g. NoiseFEM Analysis, SEA Analysis etc.) 1

= Strongly recommended = Recommended

= Recommended only if experience with similar ships is not available 1 The occurrence of tonality and/or booming in pax cabins and public spaces will be strictly assessed for hc E, 1 and 2

(see Section 3, C.1.3.4).

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Annex D

Protocol SheetA. Measurement Protocol Sheet

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I - Part 1 GL 2003

Annex D Protocol Sheet Chapter 16Page D–1

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