The Minor Servicing Exemption Scope •1910.147(a)(2)(ii) –Normal production operations are not...

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Carlos Gallegos

Assistant Area Director - Response Team

Aurora Area Office

[email protected]

The Minor Servicing

ExemptionLOTO’s Misunderstood Requirement

Goals• Review LOTO application

– Define employee roles

– Review Acceptable Isolation Devices

– Compare Machine Guarding to LOTO

– Special Equipment/Circumstances

• Discuss the “Minor Servicing Exception”

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Goals• Review Machine Guarding

– When is Machine Guarding sufficient

• Related Standards

• E-Stops

• Performance and Control Reliability

– Safeguards

– Circuit Integration (relays + contactors)

• Examples of machine guarding in Minor Servicing

Region V Top 10 Most Frequently Cited (Manufacturing)

0

50

100

150

200

250

300

350

348

168156 153

133 127

99 92 85 84

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National Top 10 Most Frequently Cited (Manufacturing FY-16)

6

1169

679

563

499 497446

316 312 301 282

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Presentation References

• 29 CFR 1910.147 The Control

of Hazardous Energy

(Lockout/Tagout)

• CPL 02-00-147 The Control of

Hazardous Energy –

Enforcement Policy and

Inspection Procedures

• ANSI B11.19-2010 American

National Standard for

Machines – Performance

Criteria for Safeguarding

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Definitions

• "Affected employee." An employee whose job

requires him/her to operate or use a machine or

equipment on which servicing or maintenance is

being performed under lockout or tagout, or

whose job requires him/her to work in an area in

which such servicing or maintenance is being

performed.

1910.147(b)

Definitions

• "Authorized employee." A person who locks out or

tags out machines or equipment in order to perform

servicing or maintenance on that machine or equipment.

• An affected employee becomes an authorized

employee when that employee's duties include

performing servicing or maintenance covered under

this section.

1910.147(b)

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Authorized Employee (CPL:Pg 1-4)

• Any employee who implements a lockout and/or tagout system procedural element on machines or equipment (for servicing and/or maintenance purposes) is considered an authorized employee:– perform energy source isolation;

– implement lockout and/or tagout on machines or equipment;

– dissipate potential (stored) energy;

– verify energy isolation;

– implement actions to release LOTO; or

– test or position machines or equipment.

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Required Training

• Authorized employees

– Recognition of hazardous energy sources

– Type and magnitude of energy in the workplace

– Methods for energy isolation / control

• Affected employees

– Purpose and use of energy control procedures

• Other employees in work area

– Procedures related to restarting machines

Servicing and/or Maintenance

(CPL:Pg 1-10)

• Workplace activities such as constructing,

installing, setting up, adjusting, inspecting,

modifying, and maintaining and/or servicing

machines or equipment.

• These activities include lubrication, cleaning or

un-jamming of machines or equipment and

making adjustments or tool changes, where the

employee may be exposed to the unexpected

energization or start-up of the equipment or

release of hazardous energy.

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Energy Isolating Device (CPL:Pg 1-5)

• A mechanical device that physically

prevents the transmission or release of

energy.

• Push-buttons, selector switches,

safety interlocks and other

control circuit type devices are

NOT energy isolating devices.

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Alternative Effective Protection?

• Employee reaches into the die in a

hydraulic press to clean die surface, which

is done about once an hour.

• The press has a light curtain for protection.

Assume this is minor servicing work.

• Is the employee considered authorized or

affected?

Adequate device for

energy isolation?

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MINOR SERVICING

EXCEPTION TO THE

LOCKOUT/TAGOUT

STANDARD

CPL 02-00-147; Pgs. 3-25 Thru 3-32

Lockout/Tagout & Employee Protection(CPL:Pg. 2-16)

• Employee Protection for Service & Maintenance Activity

is achieved by:

– Apply Full LOTO I/A/W 29 CFR §1910.147;

– Complying with the minor servicing exception to the LOTO

standard (1910.147(a)(2)(ii))

• Machine Guarding – Must provide effective employee

protection.

– Utilizing the cord and plug connected equipment or hot tap

exemptions – i.e., 1910.147(a)(2)(iii)(A) and (a)(2)(iii)(B);

– Complying with the machine or equipment testing or

positioning requirements of 1910.147(f)(1);

• Machine Guarding – Must provide effective employee

protection.

LOTO Scope

• 1910.147(a)(2)(ii)– Normal production operations are not covered by this

standard (See Subpart O of this Part). Servicing and/or maintenance which takes place during normal production operations is covered by this standard only if:

• An employee is required to remove or bypass a guard or other safety device; or

• An employee is required to place any part of his or her body into an area on a machine or piece of equipment where work is actually performed upon the material being processed (point of operation) or where an associated danger zone exists during a machine operating cycle.

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Minor Servicing Exception

• Exception to paragraph (a)(2)(ii)

– Minor tool changes and adjustments, and other minor servicing activities, which take place during normal production operations, are not covered by this standard if they are routine, repetitive, and integral to the use of the equipment for production, provided that the work is performed using alternative measures which provide effective protection (See Subpart O of this Part).

Lockout/Tagout & Machine Guarding

Servicing & Maintenance

Activity

29 CFR 1910.147

Normal Production

Operations

Subpart O29 CFR 1910.212 - 219

Employee Exposure

Employee Exposure


Servicing & Maintenance

Activity

29 CFR 1910.147

Normal Production

Operations

Subpart O29 CFR 1910.212 - 219

M

S

E

Employee Exposure

Employee Exposure

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• In order to take advantage of the limited

exception, an employer must provide

effective alternative protection in lieu of

LOTO.


Guards & Safeguarding Devices to ELIMINATE employee exposure

during the servicing and maintenance activity.

Guarded

Guarded


• Minor “servicing and/or maintenance”

activities:

– Do not require extensive disassembly of the

machinery/equipment.

– Can be accomplished safely with effective

production-mode safeguards, (Subpart O).

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(CPL:Pg. 3-26)

• Activities requiring machine or equipment shutoff anddisassembly, such as changing a machine tool or cutting blade, usually take place outside of the normal production process and require energy isolating device LOTO in accordance with §1910.147.– Changing Table Saw blade.

– Changing Grinding Wheel, etc.

• Replacement of machine or equipment components normally is not considered a routine maintenance function that can be safely accomplished when a machine or piece of equipment is operating.– belts, valves, gauges, linkages, support structure, etc. --

* Inherent & Minor - Activities must be

necessary to allow production to

proceed and be:

Routine: The activity must be

performed as part of a regular and

prescribed course of procedure

and be performed in accordance

with established practices.

Repetitive: The activity must be

repeated regularly as part of the

production process or cycle.

Integral: The activity must be

inherent to the production

process.

Normal

Production

Operation?

Lockout

Applies to All

Service/Maint

YES

YES

Lockout

AppliesNO

Service/

Maintenance

Inherent & Minor?*

Service/

Maintenance Activity/

EE Exposure to Hazard

Effective

Protection In

Use? **

NO

NOLockout

Applies

YES

Exception Applies to

Service/Maintenance

** Employer must demonstrate that

the alternative measures provide

effective protection from the

hazardous energy.(Subpart O; ANSI B11.19-2003; etc.)

Region V Minor Servicing (1910.147(a)(2)(ii)) Decision Flow Chart

MSE Operator Initiated Safety

• Is it acceptable to have the employee

follow a procedure to place the machine in

a safe mode, manual mode or pause the

operation as a part of the MSE effective

protection?

• NO! – With the exception of certain low risk

equipment and tasks.

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Westvaco Corporation Decision

(CPL:Pg. 3-26)

• OSHA issued a citation alleging a serious

violation of §1910.147 because an employer did

not lockout or tagout the slotter section of a

printer/slotter machine. Adjustments to both the

printer section and the slotter section had to be

made for each order. The average number of

orders run per day was three or four and each

order change required set-up adjustments taking

between 15 and 45 minutes to complete.


• What did the OSHRC decide and why?

– Rejected the employer's assertion that set-up activities associated with this equipment constituted minor servicing within the scope of the exception.

– Commission Concluded• setting up does not occur during normal production

operations

• work performed before the normal production operation is not covered by the exception


• While not reaching the questions of

whether the activities were minor [as are

included in this exception] or whether the

alternative protection was effective, the

Commission concluded that adjustments

made while the machine was being set-up

were not adjustments made during normal

production operations.

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MSE Operator Initiated Safety

• Must have a guard or safety device,

properly selected and applied based on

generally accepted good engineering

practices. (ANSI B11.19)

• A procedure that involves and requires the

employee to initiate the safe condition is

an Administrative Control.

Hierarchy of ControlPROTECTIVE MEASURE EXAMPLES

Elimination or

Substitution

•Eliminate human interaction in the process.

•Eliminate pinch points (increase clearance)

•Automated material handling. Etc.

Engineering Controls(Safeguarding/Safeguards)

•Guards – Fixed, Interlocked, Adjustable, Etc.

Interlocks•Presence Sensing Devices - light curtains,

safety mats, area scanners, etc.

•Two Hand Controls and Trip Devices

Awareness Means•Lights, beacons, and strobes

•Computer Warnings•Signs and Labels

•Beepers, Horns, and Sirens

Training and Procedures

(Administrative Controls)

•Safe Work Procedures

•Safety Equipment Inspections•Training

•Lockout/Tagout/Tryout

Personal Protective

Equipment

(PPE)

•Safety glasses/Face Shields

•Ear Plugs•Gloves

•Protective Footwear

•Respirators

Most Effective

Least Effective

MSE Operator Initiated SafetyIntrp Letter August 24, 2005

• In low risk minor servicing applications,

such as changing a tool bit on a milling

machine or a drill bit on a drill press,

where the activity meets all of the criteria

contained in the minor servicing exception,

servicing activities may be performed

using local disconnects or control switches

that:

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Examples Of Effective Alternative Protection

(Minor Servicing Exception)(CPL: Pgs. 3-29 thru 3-32)

• Changing a mixing blade on a vertical mixer or a drill bit on a single-spindle drill press.– machine's electrical disconnects or control

(e.g., on/off buttons or emergency stops) switches:

1. Are properly designed and applied in accordance with recognized and good engineering practice; and

2. Control all the hazardous energy and are placed in an off position; and

3. Are under the exclusive control of the employee performing the task.

• Removal of a part that is

stuck (jammed) in a plastic

injection molding machine.

– Completed a cycle and is shut-

off (using the stop push button).

– Opening interlocked sliding

operator gate guard prevents

the machine from cycling.



• The employee is positioned such that the interlock operator-gate provides the employee with sufficient protection

– an interlock gate guard is not adequate protection if the employee's entire body is inside the guard area

• Injection molding machine safety systems are designed, inspected, tested, maintained, and operated in accordance with recognized and generally accepted good engineering practices; and

• Means of control of the machine remain in the exclusive control of the person afforded the protection.



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(CPL:Pg. 3-29)

• An employer who is claiming that a

machine servicing activity is exempted by

the minor servicing exception must

demonstrate that they meet each and

every element of this exception.

– See Falcon Steel Co., 16 BNA OSHC 1179

(No. 89-2883, 1990)

• Task Creep

– Mold opened too soon or a stuck plastic part melted or became stuck such that LOTO is required because “other-than minor” cleaning must be performed.

• e.g., prying, pulling, scrapping, and/or chipping) or even machine component (e.g., die) disassembly

• This now requires LOTO


(Minor Servicing Exception)

Lockout/Tagout & Employee Protection(CPL:Pg. 2-16)

• Employee Protection for Service & Maintenance Activity is achieved by:

– Using effective machine guarding, in compliance with Subpart O, that eliminates or prevents employee exposure from the hazardous energy associated with the machines or equipment;

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Lockout/Tagout & Machine Guarding(CPL:Pg. 2-18)

• Point of operation requirements for machines, §1910.212(a)(3)(ii) requires point of operation danger zone guarding in conformity with any appropriate or applicable standard that has been adopted as or incorporated by reference into an OSHA standard.– In the absence of such standards, the guarding

device must… prevent (and not just warn or signal employees of the impending hazard) the operator from having any part of his or her body in the danger zone during the operating cycle.

Machine Guarding/ANSI B11.19 – 2003

(CPL:Pg. 2-26)

• OSHA will consider adherence with:

– 1) guards;

– 2) safeguarding devices; As primary safeguarding

methods compliant with Subpart O.

Effective Employee Protection

• What is Effective Employee Protection or

Effective Machine Guarding?

• American National Standard for Machine

Tools – Performance Criteria for

Safeguarding -- ANSI B11.19-2003

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• Safeguarding Protective Device in the 2003

ANSI standard.

– Safeguarding (protective) device: A device that

detects or prevents inadvertent access to a hazard.

Devices that detect, but do not prevent

employee exposure to machine hazards (e.g.,

through one of the four methods in (a) through (d)

above), do not comply with the machine guarding

provisions contained in Subpart O, when guards or

safeguarding devices are feasible.

Safeguarding

(CPL:Pg. 1-9)

OSH Review Commission

• “Section 1910.212(a)(1) is a general machine

guarding standard that applies to all machinery

not otherwise covered by Subpart O. The

guarding required must be provided by a

“device” that does not allow reliance upon the

skill or attentiveness of employees. It is

“intended to eliminate danger from unsafe

operating procedures, poor training or employee

inadvertence.”

Cincinnati Incorporated, OSHRC Docket No. 00-0955, Final Order Date 10/02/00





“device” that does not allow reliance upon

the skill or attentiveness of employees. It is



inadvertence.”






“device” that does not allow reliance upon

the skill or attentiveness of employees. It is



inadvertence.”


Machine Guarding/ANSI B11.19 – 2003

(CPL:Pg. 2-26)

• These methods, by design, do not prevent

employees from placing or having any part of their

bodies in the hazardous machine areas:

– Awareness devices;

– Safeguarding (work) methods;

– Safe work procedures.

• These methods provide a lesser degree of employee

protection and are considered to be secondary

control measures during normal production

operations.

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Hierarchy of ControlPROTECTIVE MEASURE EXAMPLES

Elimination or

Substitution

•Eliminate human interaction in the process.

•Eliminate pinch points (increase clearance)

•Automated material handling. Etc.

Engineering Controls(Safeguarding/Safeguards)

•Guards – Fixed, Interlocked, Adjustable, Etc.

Interlocks•Presence Sensing Devices - light curtains,

safety mats, area scanners, etc.

•Two Hand Controls and Trip Devices

Awareness Means•Lights, beacons, and strobes

•Computer Warnings•Signs and Labels

•Beepers, Horns, and Sirens

Training and Procedures

(Administrative Controls)

•Safe Work Procedures

•Safety Equipment Inspections•Training

•Lockout/Tagout/Tryout

Personal Protective

Equipment

(PPE)

•Safety glasses/Face Shields

•Ear Plugs•Gloves

•Protective Footwear

•Respirators

Most Effective

Least Effective

Complimentary Safeguarding

Equipment

• Safety Blocks, Slide Locks,

Chain Locks, and Locking Pins

• Workholding Equipment

• Enabling Devices

• Stopping Performance

Monitors

• Safety Interface Modules

– Monitoring Safety Relays

– Safety PLCs

– Safety BUS Systems

• Emergency Stop (E-Stop)

Devices– Pushbuttons

– Pull Cords (Cable Pulls, Trip

Wires)

– Body Bars

– Trip Rods

– Footswitches (without a

mechanical guard)

• Hand Tools

Equipment That Augments Safeguarding Devices:

Types of Safeguarding

• Mechanical solutions that physically

prevent or restrict access:

– Fixed Guards

– Safe Openings in Fixed Guards

– Adjustable Guards

– Moveable/Self Adjusting Guards

– Pullbacks

– Mechanical Restraints

– Moveable/Self Adjusting Guards

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Types of Safeguarding

• Mechanical solutions that prevent access

and cycle initiation (Interconnected or

Interlocked):

– Interlocked Guards (With or W/O Guard Locking)

– Type A&B Moveable Barriers (i.e. Gates)

– Moveable/Automatic Screens

– Automated Doors

– Probe Detection

Interlocks and Guarding Devices

• What do these devices have in common?

– They are all connected to the machine

controls and generate/send a command to

stop or prevent hazardous motion.

– This Protective (Safety) Stop command is

sent through the protective stop circuit. (ANSI

B11.19 - 2010: Clause 6.2.1)

Design of the SRP/CS

• One strategy used to meet these

requirements is to design the system with;

– Redundancy, and

– Monitoring to ensure that redundancy is

maintained.

• This design strategy is called “Control

Reliability” and it is used to describe the

integrity of the safety rated control system.

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Safety Related Parts of Control

System (SRP/CS)

• Are the machine’s SRP/CS “Control

Reliable”?

– What is the other question we should be

asking?

• What is the Performance Level (PL) or

Safety Integrity Level (SIL) of the

machine’s SRP/CS?

– This will tell us how well the Safety-Related

Function performs.

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ISO 13849-1 Requirement Highlights

ISO 13849-1 provides safety requirements

and guidance on the principles for the

design and integration of safety-related parts

of control systems (SRP/CS), including the

design of software. Topics include:

• Performance Levels– Categories

– Diagnostic Coverage

– Common Cause Failures

– MTTFd

• Safety Functions

• Software based parameterization

• Fault considerations and Fault exclusions

Categories – The common

misunderstandingSafety Categories ONLY describe what happens if something goes

wrong. They are NOT a measure of reliability, quality, or safety.

Instead, they help answer the question “So….If this thing fails, will the

machine still shut down?”

The higher the category, the more measures are in place to ensure the

safeguarding device does what it is supposed to do.

A higher category does NOT a mean a machine is “Safer”

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• When a single failure occurs, and it or

another subsequent failure would lead to

the inability of the safety-related

function(s) to respond to a normal stop

command or an immediate stop command,

the safety-related function shall:

Performance of the Safety-Related

Function (ANSI B11.19 - 2010: Clause 6.1)

• Until the failure is corrected or until the

control system is manually reset;

– Prevent initiation of hazardous machine

motion; or

– Initiate an immediate stop command and

prevent re-initiation of hazardous machine

motion; or

– Prevent re-initiation of hazardous machine

motion at the next normal stop command.

Performance of the Safety-Related

Function (ANSI B11.19 - 2010: Clause 6.1)

Understanding Safety Categories Categories range between B through 4. Oversimplified,

they build off each other to ensure faults don’t lead to un-

safe states:

• Category B: The use of “basic safety principles” – The use of standard components

with no fault detection or fail-safe measures

• Category 1: Category B plus the use of “well-tried components” or safety-rated

devices instead of standard components.

• Category 2: Category B plus periodic monitoring – no action required (e.g. check

engine light on car).

• Category 3: Category B plus no single fault can lead to an unsafe state, single faults

must be identified (e.g. redundancy)

• Category 4: Category B plus no accumulation of faults can lead to an unsafe state or

all faults must be individually identified (e.g. every safety device has its own safety

monitoring relay)57

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Example Safety

Function

Safety

Category

“Direct

Drive” or

“Positive Opening”

Mechanically

Linked

Contacts

Periodic

Testing

Periodic

Testing

Feedback

Feedback

Higher

Diagnostic

Coverage

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Understanding Safety Categories

Control Reliability – Performance

Level – Safety Integrity Level(Table 4 ANSI B11.0 – 2010: Clause 7.2.9.1)

Acceptable Levels(Table 4 ANSI B11.0 – 2010: Clause 7.2.9.1)

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Machine Safety Statistics: Control System Failures

HSE: Out of Control 978 0 7176 2192 7

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Today’s Machine Safety

Landscape

Avoidance:Machines are not fully

safeguarded or there has

been a minimal attempt to safeguard. “We haven’t had

an accident, haven’t had a

citation – we are good to go”

Illusion of Safety:There has been a valiant effort

to use technology and new

guarding methods to provide increased safety, but ultimately

is resulting in an illusion of

safety

Fort Knox:Limited understanding in

technology, standards, and

regulations causes an overly guarded, overly restrictive,

high cost, and productivity

limiting safety solution

Most manufacturers today are in one of these categories:

Programmable logic controllers (PLCs)?

(CPL:Pg. 1-6)

• PLC devices are NOT considered energy

isolating devices for purposes of the LOTO

standard.

• Safety functions, such as stopping or

preventing hazardous energy (motion),

can fail due to component failure, program

errors, magnetic field interference,

electrical surges, improper use or

maintenance, etc.

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What To Look For

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The Minor Servicing Exemption Scope •1910.147(a)(2)(ii) –Normal production operations are not...

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