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1. PURPOSEThis standard specifies minimum locking and tagging procedures necessary to prevent
injury by the inadvertent operation of power equipment, the inadvertent opening of valves,
inadvertent release of stored energy, or the energizing of electrical equipment. Once a
work permit requires an isolation of hazardous energy, an isolation process set forth in this
policy and procedure must be accomplished prior to issuing the work permit.
[See Blinding and Blanking]
[See Positive Isolation]
Isolation of plant and equipment is required to achieve a safe and controlled means of
access for maintenance, verification, construction, modification and decommissioning
activities and doing so ensuring that risks are as low as reasonably practicable.
The isolation certificate is to certify that the equipment has been isolated and locked off from
hazardous sources. It also provides a list of isolation locations and devices fitted to achieve
this. It shall used to record isolations carried out on:
Mechanical / process systems
Electrical systems Safety / Emergency systems
2. POTENTIAL HAZARDS
All sources of energy (i.e., pressure, electrical, hydraulic) that could result in accidental
movement of equipment, or otherwise cause damage to person, property or process must
be locked out and tagged at the main source of energy or control device.
3. APPLICATION
This policy and procedures apply to all personnel working on COPI site facilities both
onshore and offshore. This policy and procedures apply to all isolations required either as
part of the permit to work system.
4. DEFINITIONS
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Authorized employees are employees who have knowledge of the equipment and facility to
be isolated. Also, they shall have received training in the hazardous energy lockout/tagout
procedures.
Designated Group Authorized Super visors are authorized employees formally vested with the
authority to lockout/tagout equipment for a group of employees in a particular craft.
Group Lock Boxes are devices designed to secure the keys for group locks. These boxes
shall be designed in such a manner that keys for group locks is put inside and secured byattaching the personal locks of the authorized employees working on the equipment.
ENERGY - Mechanical motion; potential energy due to pressure, as in hydraulic,
pneumatic, or vacuum systems, or it can be due to gravity; or springs; generated or static
electrical energy; thermal energy resulting from high or low temperatures; radiation energy;
or the unexpected flow of gas, vapor, or liquid into an open process vessel or piping system
undergoing maintenance.
ENERGY SOURCE - Any source of electrical, mechanical, hydraulic, pneumatic, chemical,
thermal, gravitational, radiation, or other energy.
Blind Flange - Flange used for isolation purposes rated to the maximum operating or test
pressure which may be applied. Meets CII standard.
Block Valve - Ball valve or gate valve normally, butterfly valves are acceptable in water
flood applications less than 150 psi.
Full thickness - Solid Metal plate cut to form isolation between faces Skillet of two flanges
rated to the maximum operating or test pressure which may be applied. Meets CII
standard and used in conjunction with gaskets meeting the CII standard.
Single Valve A single closed, locked, non-leaking block valve used Isolation to isolate
pressure
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5. TRAINING
Training shall be provided to ensure that the purpose and function of the lockout / tagout
program is understood by the employees and that the knowledge and skills required for the
safe application, usage, and removal of energy controls are acquired by employees.
This training shall be recorded. Record shall include date, names, and subject matter.
Retraining shall be provided whenever:
- there is a change in the employees job assignments
- there is a change in machines, equipment or processes that present new hazards
- there is a change in lockout/tagout procedures.
6. GENERAL REQUIREMENTS
Hazardous energy lockout/tagout work shall be attempted only by authorized employees,who shall notify the supervisor of the facility before work begin
The process or mechanical isolation design should be determined and carried out as defined
in Appendix A, table 1 to 7, and Typical example (Appendix B). However this should not be
regarded as a replacement for competent technical judgement.
These policy and procedures support the Work Permit System. The requirement for an
isolation can not be raised without the appropriate work permit.
The Site HSE Leader shall have a master or duplicate key that fits all locks in their area of
responsibility:
These individuals are the only ones, other than the person who set the lock, with the
authority to approve lock removal.
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Locks specifically designated for use in the lockout procedure shall be provided by
ConocoPhillips Indonesia. The locks utilized shall be HIGH SECURITY MASTER PAD
LOCKS that are keyed differently. Each lock and key shall be stamped in order to identify
them by location. They shall be assigned individual numbers.
Each work location is to be equipped with a locked box containing lock and key sets, lockout
tags, multiple lock devices, and a registration book.
Entries into the registration Log book must, as a minimum, indicate location and purpose of
isolation/lockout, dates and times isolation/lockout was initiated and completed, and thecraftsman's name.
The number of locks required at each location is dependent upon utilization requirements.
These locks must be put into the lock box at designated controlled area and the lock must be
administered and controlled.
All work locations are required to inventory their lock boxes weekly and ensure that the
correct number of locks and keys are accounted for and to familiarize themselves with logbook entries and active locks in place. Any missing locks or keys are to be reported to the
master key holder immediately. This inventory check shall be noted in the logbook.
The authorized employee shall have knowledge of the type and magnitude of the energy, the
hazards of the energy to be controlled and the method or means to control the energy prior
to locking out equipment.
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Only the Electrical / System or his designee shall test, energize, de-energize, and/or lockout
primary electrical equipment. Primary electrical equipment is defined as equipment such as
generators, switch gear, controllers, transformers and power cables that transmit or control
electrical power in excess of 600 volts.
Control devices such as push buttons, selector switches, or electrical interlocks that de-
energize electric power currents indirectly through contractors, controllers, or electrically
operating disconnecting devices are not to be utilized as the sole disconnecting means.
Applicable craft shall remove fuses and positively ensure the circuit is dead when it is notpossible to apply a lock.
When locks cannot be applied or are not feasible, or when it can be demonstrated that
tagout procedures will provide equivalent safety, tagouts shall be permitted to be used by
authorized employees. The use of tagouts shall be accompanied by additional safety pre-
cautions such as isolating the circuit or opening a connecting device.
A DANGER tag is to be signed, dated and attached by the applicable craftsman at the pointwhere the circuit is isolated. Tags shall be water proof and conform to OSHA 1910-145.
Both sides of the tag shall have the word "DANGER" in white on a red background with a
black border. The inscription on one side of the tag shall have the inscription "DO NOT
REMOVE THIS TAG" & "SEE OTHER SIDE". This tag shall indicates isolation certificate
number related to this isolation.
A qualified person shall physically verify that the equipment cannot be energized or restarted
once a lockout has been made.
Further Guidance on process isolation and electrical isolation is defined in Appendix C, D.
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Once the work leader performing the work pick up the work permit to commence the work,
he/she is subject to keep the lock related to his/her job.
Upon completion of the work, the work leader return the work permit to the central control
point to indicate that he finished the work. The work leader who performed isolation
previously shall accomplish de-isolation after all work permit related to this isolation certificate
finished. The isolation certificate in the central permit control point must be picked up to
record de-isolation process and return back to the central permit control point upon
completion De-isolation.
The authorized employee and the applicable craftsmen shall conduct a visual inspection to
ensure the area is safe prior to energizing/starting the equipment/electrical circuit.
The authorized employee nominated to maintain the lock box shall ensure that all craft locks
have been removed and returned to the lock box when work is completed.
Upon completion of work covered by isolation certificate, work permit authorizer must
complete isolation certificate to indicate the work is complete, all isolations have beenremoved and closed the certificate.
Annually, each site shall review the site lock and tag procedure to ensure that the procedure
is adequate and is being implemented.
A hasp can be used when a multiple work requires a lock at the same lock holder location. If
this is impractical, one work is only required to lock the isolation drawer of the other work.
8. OWN ISOLATIONS
When an R.E.P (Responsible Electrical Person). or, other authorised person, feels that the
Work Leader is competent to perform their own isolations associated with the work they will
be carrying out, and conditions 12.6.1 to 12.6.6 apply, then the isolations can be deemed
own isolations.
The competent person who will be carrying out the isolations/deisolations and work will be
responsible for completing the plan if required and signing prepared by and accepted
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by. He will also be responsible for ensuring isolations and work satisfies 12.6.1 to 12.6.6 at
all times.
The REP or other authorised person should write own isolations on the Work permit,
identifying the equipment/systems to which these isolations apply.
In all own isolation cases, it will be necessary for the Work Leader to carry out his own
isolations / de-isolations throughout the course of the work subject to the following criteria:
The person carrying out "own isolations" must have been assessed as competent to
carry out such isolations and authorised in accordance with Site Leader.
Own isolations shall only be carried out by a competent person for work in which
they are personally involved.
Own isolations shall remain in place only as long as the competent person is
actually involved in the work.
Additional persons under the control of the Work Leader may only work on
equipment isolated under an Own Isolation if the following conditions are satisfied;
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(i) An Electrical Work Plan shall be completed.
And
(ii) All persons assisting the Work Leader shall agree and sign the Work Plan. The
Work Leader shall issue each person with their own dedicated Lock & Key and
ensure that each shall apply their lock along with his own to act as secondary
isolation and ensure their safety for as long as they are involved in the work.
The Work Leaders lock shall be the first applied and the last removed, providing
he has satisfied himself that it is safe to do so.
or
(iii) Where it is not possible to apply multiple padlocks all additional personnel shall
be under the direct and continuous supervision of the Work Leader whilst they
are at the location of the equipment.
The Own Isolation shall be recorded on an Own Isolation Certificate and in the local
Isolation Logbook .
The Own Isolation Certificate shall be appended to the Work Leaders copy of the
Work Permit and isolations/de-isolations recorded on the Certificate by the Work
leader as and when they take place.
9. SANCTION TO TEST
Under the current Permit to Work procedure there is no facility to temporarily de-isolate
equipment for test purposes, when controlled under a Permit and associated Isolation
Certificate. In this case a separate Permit requires to be raised for testing purposes.
However, for equipment being worked on under the control of an Own Isolation, the
isolation can be removed, to facilitate testing, subject to the conditions laid down in Section
12.6.
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Appendix A.
Process Isolation Selection Flow Scheme
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Table 1
Situation Parameter
Typical Examples
Type Description Onshore Offshore
A Congested or confined equipment or>20 people at risk.
Offshore there is the potential forescalation resulting in the need forplatform evacuation.
Crude distiller unit,catalytic cracker
plant. Village ortown within range oftoxic effects
Compressionmodule heavily
populated with pipework and objects of box typeconstruction.
B Open process storage or producetransfer plant or 11 to 20 people atrisk. Offshore open or less congestedmodules where explosion hazard isminimal or escalation beyond theimmediate area is unlikely. Large fireswith potential for local damage andmultiple fatalities.
Treater unit, LPGspheres, road-car-loading gantry.
Module containinglarge cylindricalvessels, such asseparators, widelyseparated.
C Storage area or 6 to 10 people at risk.Offshore an area where gas is unlikely
to accumulate to hazardous levels withminor fires contributing the highestrisk.
Tank farm, pumpingmanifold,
unprotected controlroom or outsideworkers within rangeof toxic effects.
Wellhead modulesor other non-
enclosed spacesopen on two or moresides.
D Few i tems of equipment in an openarea or 3 to 5 people at risk. Offshoreutility systems with the potential tocause fatalities or structural damage.
Isolated pumphouse. Modules containingtemperature or high-
pressure utilitysystems or corrosivesubstances.
E Remote single items or 1 or 2 peopleat risk. Offshore minor fires that areeasily contained.
Remote pump orvessel.
Note:
The numbers of people at risk includes those not in the immediate vicinity but who
might be exposed to the hazard in the event of a release of hazardous substance.
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Table 2
Substance Parameter
Type
Description
1 Toxic gases e.g. HF, CI2, SO2, H2S, HCN, HCI, CO
Note: Toxic liquids such as CI2 and SO2 require special treatment sinceleaks may cause toxic effects over a wide area. In such cases thehighest standard of isolation should be employed.
2 LPG, NGL or flammables above a temperature where more than about50% weight would be flash on release. Material above auto-ignition
temperature.3 Flammable liquids above their flashpoint e.g. condensate.
4 Flammable gases.
5 Flammable liquids below their flashpoint e.g. methanol
6 Other hazardous fluids, e.g. steam, high temperature or lowtemperature (cryogenic) fluids, corrosives, acids, asphyxiants, etc.
7 Non-hazardous substances (Note that substances such as water andnitrogen may be hazardous in some situations).
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Table 3
Effects Matrix
Situation (from Table 1)
SubstanceType
(from Table2)
A B C D E
1 10 10 9 8 7
2 9 8 5 4 3
3 8 6 4 3 2
4 5 4 3 2 1
5 4 3 2 1 1
6 3 2 1 1 1
7 1 1 1 1 1
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Table 4
Time Matrix
Duration
Frequency < 1 Shift > 1 Shift > 7 Days
Daily 10 10 -
Weekly 7 10 -
Monthly 3 7 10
Annually 2 3 7
Occasionally 1 2 3
Table 5
System Pressure
Line Size >100
barg
>50 barg >20 barg > 10
barg
8 10 8 6 5 4
6 8 6 5 4 3
4 6 4 3 3 2
2 4 3 2 2 1
< 1 3 2 2 1 1
Note:
For satellites this is the cumulative time that the platform is manned during
which the isolation is in place.
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Table 6
Selection of Isolation Method
Hazard Factor =
Release Factor x Time Factor xEffects Factor
Preferred Isolation Method
30 single valve
31 to 150 double valve
151 to 450 double block and bleed
451 to 600 single valve, spade andbleed
>600 double block, bleed andspade
Table 7
Special Techniques
Application
Technique Process plant Pipelines
Valves Standard Standard
Spool removal Standard Standard
Spades/spectacle blinds Standard Standard
Pipe stoppers Special Standard
Line plugs (e.g. stopple) Special Standard
Line plugs (mechanical seals) Special Special
Pipe freezing Special Special
Pigs Not applicable Special
Inflatable bags Special Special
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Appendix B
Typical Examples
8 inch LPG line at 50 barg in a congested process plant (so there is a VCE
potential. Isolation is to be carried out once a year for three weeks
Effects factor = 9(A.2)
Release factor = 10
Time Factor = 7
Hazard factor = 630 (9 x 10 x 7)
Isolation is Method 5 Double Block and Bleed
4 inch Condensate line at 10 barg and 20 degrees celsius in a tank farm
manifold where one or two workers might be present. Pool fire and escalation
hazard. To be isolated occasionally for several weeks.
Effects factor = 4(C.3)
Release factor = 3
Time factor = 3
Hazard factor = 36
Isolation is Method 2 Double Valve
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Appendix C.
Process IsolationsPRINCIPLES OF ISOLATION crown copyright 1997
The Primary objective is to always use the highest level of isolation, which is
reasonably practicable.
The adequacy of the isolation should reflect the reasonably foreseeable risk and
consequences should that risk be realised.
Isolations should be secure throughout the duration of the activity
Isolations should be adequately tested to prove effectiveness.
Plant and equipment should be correctly and clearly identified.
Isolations applied should be adequately recorded.
Personnel should be competent in their knowledge and understanding of hazards, the
process plant and the procedures manual and in the skills necessary to effect and
remove isolations from the plant.
The requirement for process isolation shall be identified through a task risk
assessment and subsequently the permit to work.
The risk-based methodology to be used for determining process isolation is given inAppendix B. This should be used as a selection tool but not as a
replacement for competent technical judgement.
Information to carry out the risk based isolation design will be made available on the
permit by identifying the system to be isolated and the work to be carried out. Where
the isolation method identified by best practices is not achievable then a lower level of
isolations may be used, as long as the risks have been identified as being as low as
reasonably practicable through risk assessment.
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CONFINED SPACE ENTRY crown copyright 1997
Entry into confined spaces is the most hazardous activity for anyone who works on
process plant. Vessels, such as separators, tanks, reactors or distillation columns, are
the most obvious form of confined space, yet sumps, pig launchers/receivers or work
inside pipes can present the same dangers. Hazards can arise from the presence of
flammable or toxic vapours from process materials, or evolve from residues, but the
less obvious dangers of oxygen depletion or carbon dioxide build-up should not be
ignored. People can also be drowned by the ingress of water or asphyxiated by
granular solids. In these circumstances the highest standards of isolation are
paramount and physical disconnection (spool removal) or the insertion of spectacle
blind are acceptable methods. It is particularly important that isolation is installed as
close as possible to the vessel.
Some confined spaces contain electrical and mechanical equipment with power
supplied from outside the space. Unless the risk assessment specifically enables the
system of work to allow power to remain on, either for the purpose of the task being
undertaken or a vital service (i.e. lighting), vital communications, fire fighting,
pumping where flooding is a risk, or cables distributing power to other areas) the
power should be disconnected, separated from the equipment, and a check made to
ensure isolation has been effective. Check must be made to ensure there is no stored
energy of any kind left in the system that could activate the equipment inadvertently.
Isolation Methods
The isolation method identified from Appendix B Table 6, and from Confined Space
Entry risk assessment are defined as follows:
Physical Separation (PS): A method of isolation whereby a complete
separation between the energy source and the
plant/equipment is achieved.
Physical Barrier (PB): By insertion of a spade/spectacle blind of the
correct rating as close to the section to be isolated.
Single Isolation Valves (SIV): By the locking of a single isolation valve in the
closed position.
Double Block and Bleed Valves: An isolation method consisting of an
arrangement of two block
(DBB) valves with a bleed valve located in between.
The isolation method required shall be applied to all boundaries of interconnecting
isolatable sections of plant.
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APPENDIX D.
ELECTRICAL ISOLATIONS
Electrical isolations apply to all sources of electrical energy which can give rise to
electric shock, electrical burns or which cause incendive sparks in hazardous areas.
The competency required to design, implement and authorise electrical isolations shall
be met.
D.1. PREPARATION OF ELECTRICAL WORK PLAN (EXHIBIT B)
On receipt of electrical isolation request, which requires preparation of "plan, the REP
or other authorised person must complete the step-by step electrical work plan.
The step-by-step plan should, where relevant, show the following:
Alternative power feeding arrangements
All points of isolation of potential supplies
All points where circuit main earths and additional earths will be applied
All positions to be tested dead
All positions where locks are to be fitted
Details of work to be done in relation to isolation/deisolation sequence
Details of testing to be done and precautions when removing earths and
applying test voltages.
The person who prepares the plan should sign this plan.
NOTE:
For Own Isolations the person doing the isolations will be responsible for
completion of the plan.
D.2. ACCEPTANCE OF PLAN
When the electrical work plan have been completed by the REP, or other authorised
person, should nominate competent person(s) to perform the isolations/work and sign
plan prepared by.
The persons nominated to perform the isolations/work should sign plan accepted by
if they agree with the plan.
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If required other personnel working on the isolated equipment can view plan for
assurance and confirmation of isolation methods. If this is done they should sign plan
agreed by. Where more than one person is working on equipment isolated on an Own
isolation all persons assisting the Work Leader shall agree and sign the Electrical Work
Plan.
D.3. ISOLATIONS / DEISOLATIONS
As isolations are completed and locked off lock numbers, date and signatures should
be entered onto the general isolation certificate.
Permission to de-isolate has to be obtained from the general isolation certificate
authoriser. This can only be done on completion of all work and cancellation of all
permits.
All details of isolations and de-isolations should be recorded in local isolation logs
which should be kept in every switchroom and at a suitable place when not located in
a switchroom.
D.4. PRE-ENERGISATION CHECKS
Prior to de-isolation or switching operations, all equipment / switchgear should be
checked for foreign objects which would likewise cause a short circuit i.e. tools, wiringdebris, etc. Field-end equipment should be checked to ensure all cable terminations
are complete, enclosures are closed-up and cover screws/fixing bolts re-instated.
Subsequent to the visual inspection of field equipment Insulation Resistance and
continuity tests shall be carried out at the Switchgear, MCC cubicle or Distribution
Board to confirm the integrity of the circuit. Proprietary test leads shall be used in all
cases in accordance with HSE Guidance Note GS38 Electrical Test Equipment for use
by electricians.
D.5. ISOLATION PRACTICES
D.5.1. PROVING DEAD
Prior to commencing work on equipment that has been electrically isolated the
equipment conductors should be proved dead at the point(s) of work.
A proprietary live line tester or Voltage Indicator shall be utilised for the
purpose of Proving Dead. The rating of the tester/indicator shall be checked
for suitability against the equipment rating prior to testing. Multi-meters shall
not be used for proving dead.
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The Live Line Tester or Voltage Indicator shall be inspected for signs of
damage or deterioration prior to use. The test instrument itself shall be
proved immediately before and immediately after testing the conductors.
D.5.2 EARTHING
Isolation and proving dead will prevent the equipment from becoming charged
by connection to its own or normal sources of electrical energy. The presence
of electrical energy as a result of electromagnetic induction, mutual
capacitance or stored electrical energy should be guarded against by applying
earth connections for the duration of the work, after initial discharge of the
circuit. Where possible e.g. on HV Switchgear, these earth connections shouldbe applied by means of purpose-built Circuit Main Earthing facilities.
The application of earths shall be recorded on the Electrical Work Plan and
Isolation Certificate. Likewise, upon completion of the work it is important that
all Circuit Main and Additional Earths are removed and checked off on the
Isolation Certificate and Electrical Work Plan.
D.5.3 CONTROL CIRCUIT ISOLATIONS
In all cases where it is possible to receive a start/close signal from an external
control circuit, the electrical isolation of plant equipment shall include the
isolation of the control circuit.
If energisation of the control circuit is required for function-testing this shall be
arranged in consultation with the REP and itemised on the Work Plan/Own
Isolation Certificate.
D.5.4 MCC STARTER CUBICLES
Where electrical isolations are applied at MCC Cubicles the following practices
should be observed;
Where the isolation is for work involving direct access to the conductors feeding
the equipment then physical separation of the supply should be ensured. This
may involve withdrawal of the starter cubicle (if withdrawable), removal of
fuses or physical disconnection of conductors. The reliance upon isolators or
isolating switches only as a means of isolation is not permitted.
Where the isolation is for work not involving direct access to the conductors,
e.g. mechanical work associated with pump or fan-motor assemblies, then
reliance upon the isolator/isolating switch may be permitted only if its design
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conforms with BSEN 60947-3. The above requirements recognise the risk of
failure to operate of older Isolators/Isolating switches, as evidenced by a
number if incidents within the Industry in recent years.
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Special techniques
It may not be always reasonably practicable to isolate a section of pipe using the
methods previously referred to. In such cases other alternatives may need to be
considered to effect an isolation. Such methods should only be used following a task-
specific risk assessment. Isolation methods deemed Special Techniques, and under
which circumstances they can be used, are identified in Appendix A, Table 7.
Techniques falling into this category include, but are not restricted to the following.
Pipe plugs
Pipe stoppers
Inflatable bags
Hot tapping and stoppling
Pipe freezing
Pigs
SHORT DURATION WORK crown copyright 1997
In some cases the time needed to install a final isolation is substantial and for some
work it may therefore be acceptable to use a different standard of isolation.
Two factors need to be considered when deciding what is short duration work:
the work should take less time to complete than the time needed to
install and remove the final isolation; and
the risk of loss of containment from completing the work with the short
duration standard of isolation should not be greater than the risk of using
a final standard of isolation. Additional risks associated with the
installation and the removal of the final isolation can be taken into
account.
A decision to use "short duration" standards of isolation should be supported by a risk
assessment to justify the variation from a more secure "final" isolation method.
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When using short duration standards, isolation valves need to be proved before
proceeding, and then monitored for leakage during the work activity. If a short
duration isolation is in use, the work site should not be left unattended. This will allow
prompt remedial action if a leak develops. Short duration work should not extend
beyond one operating shift and measures to be implemented to mitigate the effects of
a release, e.g. adjacent work activities should be restricted, local gas detection
equipment provided, and fire fighting equipment made available locally.