U.S. Department of Labor Assistant Secretary for
Occupational Safety and Health
Washington, D.C. 20210
OSHA Instruction STD 1-7.3 SEP 11 1990 Directorate of Compliance
Programs
SUBJECT: 29 CFR 1910.147, the Control of Hazardous Energy
(Lockout/Tagout)--Inspection Procedures and Interpretive
Guidance
A. Purpose. This instruction establishes policies and provides
clarification to ensure uniform enforcement of the Lockout/Tagout
Standards.
B. Scope. This instruction applies OSHA-wide.
C. References.
1. General Industry Standards, 29 CFR 1910, Subpart O, Subpart
S, and other specific subparts.
2. OSHA Instruction CPL 2.45B, June 15, 1989, the Revised
Field Operations Manual (FOM).
D. Effective Date of Requirements. All requirements of 29 CFR
1910.147 have an effective date of January 2, 1990. The information
collection requirements contained in this section have been approved
by the Office of Management and Budget (OMB) and listed under OMB
control number 1218-0150, as announced at Federal Register, Volume
54, No. 199, October 17, 1989.
E. Action. Regional Administrators and Area Directors shall
ensure that the guidelines and interpretive guidance in this
instruction are followed and that compliance officers are familiar
with the contents of the standard.
F. Federal Program Change. This instruction describes a Federal
program change which affects State programs. Each Regional
Administrator shall:
1. Ensure that this change is forwarded to each State
designee.
OSHA Instruction STD 1-7.3 SEP 11 1990 Directorate of
Compliance Programs
2. Explain the technical content of this change to the State
designee as requested.
3. Ensure that State designees acknowledge receipt of this
Federal program change in writing, within 30 days of notification,
to the Regional Administrator. This acknowledgment should include
the State's intention to follow the inspection guidelines
described in this instruction, or a description of the State's
alternative guidelines which are "at least as effective" as the
Federal guidelines.
a. If a State intends to follow the revised inspection
guidelines described in this instruction, the State must submit
either a revised version of this instruction, adapted as
appropriate to reference State law, regulations and
administrative structure, or a cover sheet describing how
references in this instruction correspond to the State's
structure. The State's acknowledgment letter may fulfill the
plan supplement requirement if the appropriate documentation is
provided.
b. Any alternative State inspection guidelines must be
submitted as a State plan supplement within 6 months. If the
State adopts an alternative to Federal guidelines, the State's
submission must identify and provide a rationale for all
substantial differences from Federal guidelines in order for
OSHA to judge whether a different State guideline is as
effective as a comparable Federal guideline.
4. After Regional review of the State plan supplement and
resolution of any comments thereon, forward the State submission
to the National Office in accordance with established procedures.
The Regional Administrator shall provide a judgment on the
relative effectiveness of each substantial difference in the State
plan change and an overall assessment thereof with a
recommendation for approval or disapproval by the Assistant
Secretary.
5. Review policies, instructions and guidelines issued by the
State to determine that this change has been communicated to State
personnel.
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OSHA Instruction STD 1-7.3 SEP 11 1990 Directorate of
Compliance Programs
G. Background. The Standard for Control of Hazardous Energy
(Lockout/Tagout), 29 CFR 1910.147, was promulgated on September 1,
1989, at Federal Register, Volume 54, No. 169 (pages 36644-36696),
and was effective on January 2, 1990, as announced at Federal
Register, Volume 54, No. 213, November 6, 1989 (page 46610).
Previously existing section 29 CFR 1910.147 was redesignated as 29
CFR 1910.150, Sources of Standards.
1. Since the inception of its enforcement program, OSHA has
relied on the "General Duty Clause" (Section 5(a)(1) of the OSH
Act) to ensure that employers safeguarded their maintenance and
service employees through the use of lockout/tagout from the
hazards involving the unintentional release of hazardous energy.
Such violations reached a level so significant that the
development and promulgation of a lockout/tagout standard was
required.
2. The new rule addresses practices and procedures that are
necessary to disable machinery or equipment and to prevent the
release of potentially hazardous energy while maintenance and
servicing activities are being performed.
3. The lockout/tagout provisions of this standard are for the
protection of general industry workers while performing servicing
and maintenance functions and augment the safeguards specified at
Subparts O, S, and other applicable portions of 29 CFR
1910.
H. Inspection Guidelines. The standard incorporates performance
requirements which allow employers flexibility in developing
lockout/tagout programs suitable for their particular
facilities.
1. The compliance officer shall determine whether servicing
and maintenance operations are performed by the employees. If so,
the compliance officer shall further determine whether the
servicing and maintenance operations are covered by 29 CFR
1910.147 or by the requirements or employee safeguarding specified
by other standards as discussed in I.1.
2. Evaluations of compliance with 29 CFR 1910.147 shall be
conducted during all general industry inspections
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OSHA Instruction STD 1-7.3 SEP 11 1990 Directorate of Compliance
Programs
within the scope of the standard in accordance with the FOM,
Chapter III, D.7. and 8., Additional Information to Supplement
Records Review. The review of records shall include special
attention to injuries related to maintenance and servicing
operations.
3. The compliance officer shall evaluate the employer's
compliance with the specific requirements of the standard. The
following guidance provides a general framework to assist the
compliance officer during inspections:
a. Ask the employer for any hazard analysis or other basis
on which the program related to the standard was developed.
Although this is not a specific requirement of the standard,
such information, when provided, will aid in determining the
adequacy of the program. It should be noted that the absence of
a hazard analysis does not indicate non-compliance with the
standard.
b. Ask the employer for the documentation including:
procedures for the control of hazardous energy including
shutdown, equipment isolation, lockout/tagout application,
release of stored energy, verification of isolation;
certification of periodic inspections; and certification of
training. The documented procedure must identify the specific
types of energy to be controlled and, in instances where a
common procedure is to be used, the specific equipment covered
by the common procedure must be identified at least by type and
location. The identification of the energy to be controlled may
be by magnitude and type of energy. Note the exception to
documentation requirements at paragraph 1910.147(c)(4)(i),
"Note". The employer need not document the required procedure
for a particular machine or equipment when all eight(8) elements
listed in the "Note" exist.
c. Evaluate the employer's training programs for
"authorized", "affected", and "other" employees. Interview a
representative sampling of selected employees as a part of this
evaluation (29 CFR 1910.147 (c)(7)(i)).
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OSHA Instruction STD 1-7.3 SEP 11 1990 Directorate of
Compliance Programs
(1) Verify that the training of authorized employees
includes:
(a) Recognition of hazardous energy;
(b) Type and magnitude of energy found in the
workplace;
(c) The means and methods of isolating and/or controlling
energy; and
(d) The means of verification of effective energy control,
and the purpose of the procedures to be
used.
(2) Verify that affected employees have been instructed in
the purpose and use of the energy control
procedures.
(3) Verify that all other employees who may be affected by
the energy control procedures are instructed about the procedure
and the prohibition relating to attempts to restart or
reenergize such machines or equipment.
(4) When the employer's procedures permit the use of tagout,
the training of authorized, affected, and other employees shall
include the provisions of 29 CFR 1910.147(c)(7)(ii) and
(d)(4)(iii).
d. Evaluate the employer's manner of enforcing the program
(29 CFR 1910.147 (c)(4)(ii)).
4. In the event that deficiencies are identified by following
the guidelines in H.3. of this instruction, the compliance officer
shall evaluate the employer's compliance with specific
requirements of the standard, with particular attention to the
interpretive guidance provided in section I. and to the
following:
a. Evaluate compliance with the requirements for periodic
inspection of procedures.
b. Ensure that the person performing the periodic inspection
is an authorized employee other than
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OSHA Instruction STD 1-7.3 SEP 11 1990 Directorate of Compliance
Programs
the one(s) utilizing the procedure being
inspected.
c. Evaluate compliance with retraining requirements which
result from the periodic inspection of procedures and practices,
or from changes in equipment/processes.
d. Evaluate the employer's procedures for assessment, and
correction of deviations of inadequacies identified during
periodic inspections of the energy control
procedure.
e. Identify the procedures for release from lockout/tagout,
including:
(1) Replacement of safeguards, machine or equipment
inspection, and removal of non-essential tools and
equipment;
(2) Safe positioning of employees;
(3) Removal of lockout/tagout device(s); and
(4) Notification of affected employees that servicing and
maintenance is completed.
f. Ensure that when group lockout or tagout is used, it
affords a level of protection equivalent to individual lockout
or tagout as amplified in I.7. through I.9. of this
instruction.
5. The lockout/tagout standard is a performance standard;
therefore, additional guidance is provided in Appendix C of this
instruction to assist in effective implementation by employers and
for uniform enforcement by OSHA field staff.
I. Interpretive Guidance. The following guidance relative to
specific provisions of 29 CFR 1910.147 is provided to assist
compliance officers in conducting inspections where the standard may
be applicable:
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OSHA Instruction STD 1-7.3 SEP 11 1990 Directorate of
Compliance Programs
1. Scope of the Standard.
a. The standard as specified in 29 CFR 1910.147(b), applies
to any source of mechanical, hydraulic, pneumatic, chemical,
thermal, or other energy.
(1) The standard applies to piping systems, and requires, at
29 CFR 1910.147(d)(5), that all potentially hazardous stored or
residual energy be relieved, disconnected, restrained, and
otherwise rendered safe. If there is a possibility of
reaccumulation of stored energy to a hazardous level, continued
monitoring shall be performed while a potential hazard
exists.
(2) The standard also applies to high intensity
electromagnetic fields regulated at 29 CFR 1910.97, nonionizing
radiation. Such electromagnetic devices shall be deenergized and
held off whenever workers are present within a high intensity
ambient field.
(3) Servicing/maintenance of fire alarm and extinguishing
systems and their components, upon which other employees are
dependent for fire safety, are not required to meet the
requirements of this standard if the workers performing
servicing/maintenance upon fire extinguishing systems are
protected from hazards related to the unexpected release of
hazardous energy by appropriate alternative measures. (See 29
CFR 1910, Subpart L.)
b. The standard does not apply to servicing and maintenance
when employees are not exposed to the unexpected released of
hazardous energy.
c. Safeguarding workers from the hazards of contacting
electrically live parts (exposure to electric current) continues
to be regulated at Subpart S.
d. Servicing and maintenance functions conducted during
normal production operations are not regulated at 29 CFR
1910.147 if the safeguarding
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OSHA Instruction STD 1-7.3 SEP 11 1990 Directorate of Compliance
Programs
provisions of Subpart O or other applicable portions of 29
CFR 1910 prevent worker exposure to hazards created by the
unexpected energization or start-up of the machine or equipment.
However, lockout/tagout procedures are required if the
production safeguards are rendered ineffective while an employee
is exposed to hazardous portions of the machines or
equipment.
e. Generally, activities such as lubrication, cleaning or
unjamming, servicing 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, are covered by this standard.
However, 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 equipment for
production, and if work is performed using alternative
protective measures which provide effective employee protection.
Thus, lockout or tagout is not required by this standard if the
alternative protective measures enable the servicing employee to
clean or unjam, or otherwise service the machine without being
exposed to unexpected energization or activation of the
equipment, or the release of stored energy.
NOTE: Appendix C, section A, provides further guidance in
this area.
f. The exclusion of plug and cord connected electric
equipment, at 29 CFR 1910.147(a)(2)(iii)(A), applies only when
the equipment is unplugged and the plug is under the exclusive
control of the employee performing the servicing and/or
maintenance.
(1) The plug is under the exclusive control of the employee
if it is physically in the possession of the employee, or in
arm's reach and in line of sight of the employee, or if the
employee has affixed a lockout/tagout device on the
plug.
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OSHA Instruction STD 1-7.3 SEP 11 1990 Directorate of
Compliance Programs
(2) The company lockout/tagout procedures required by the
standard at 29 CFR 1910.147(c)(4) shall specify the acceptable
procedure for handling cord and plug connected
equipment.
2. Procedures.
a. The employer must develop and document procedures and
techniques to be used for the control of hazardous energy. The
standard, at 29 CFR 1910.147(c)(4)(i) "Note," identifies eight
(8) conditions that must exist in order to excuse the employer's
obligation to maintain a written procedure for a specific
machine or piece of equipment.
b. 29 CFR 1910.147(d)(3) and (d)(5) provide that energy
isolation be a mandatory part of employer's control procedure
where either a lockout system or a tagout system is
used.
c. Similar machines and/or equipment (such as those using
the same type and magnitude of energy and the same or similar
types of controls) can be covered with a single written
procedure.
3. Lockout vs. Tagout.
a. OSHA has determined that lockout is a surer means of
ensuring deenergization of equipment than tagout, and that it is
the preferred method.
b. 29 CFR 1910.147(c)(3)(ii) provides that: When using a
tagout program in those instances where the equipment is capable
of being locked out, the employer shall demonstrate that the
tagout program will provide a level of safety equivalent to the
obtained when using a lockout program. Additional means beyond
those necessary for lockout are required. (Additional means
include: additional safety measures such as the removal of an
isolating circuit element, blocking of a controlling switch,
opening of an extra
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OSHA Instruction STD 1-7.3 SEP 11 1990 Directorate of Compliance
Programs
disconnecting device, or the removal of a valve handle to
reduce the likelihood of inadvertent
energization.)
c. 29 CFR 1910.147(c)(4)(ii) provides that: Where
lockout/tagout programs are used, the employer is required to
implement an effective means of enforcing the
program.
d. 29 CFR 1910.147(c)(7)(ii)(A-F) provide that: Additional
training of authorized, affected and other employees is required
when tagout programs are used.
e. 29 CFR 1910.147(c)(5)(ii)(A) requires that lockout and
tagout devices be capable of withstanding the environment to
which they are exposed. Devices which are not exposed to harsh
environments need not be capable of withstanding such
exposure.
f. 29 CFR 1910.147(c)(5)(ii)(C)(2) requires that tagout
devices having reusable, non-locking, easily detachable means of
attachment (such as string, cord, or adhesive) are not
permitted.
4. Employees and Training.
a. The standard recognized three types of employees:
(1)"authorized" and (2)"affected", defined in 1910.147 (b), and
(3)"other", defined in 1910.147(c)(7)(ii)(C). Different levels
of training are required based upon the respective roles of
employees in the control of energy and the knowledge which they
must possess to accomplish their tasks safely and to ensure the
safety of fellow workers as related to the lockout/tagout
procedures (1910.147(c)(7)(i)).
b. Employees who exclusively perform functions related to
normal production operations, and who perform servicing and/or
maintenance under the protection of normal machine safeguarding,
need only be trained as "affected" (rather than "authorized")
employees even if tagout procedures are used. (See, I.1.d. and
I.1.e. of this instruction.)
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OSHA Instruction STD 1-7.3 SEP 11 1990 Directorate of
Compliance Programs
c. The employer's training program must cover, at a minimum,
the following three areas: energy control program, elements of
energy control procedures relevant to employee duties, and the
pertinent requirements of the standard (1910.147(c)(7) and (d)
through (f)).
d. The employer must provide:
(1) Effective initial training;
(2) Effective retraining as needed; and
(3) Certification of training. The certification shall
contain each employee's name and dates of training
(1910.147(c)(7)iv)).
e. Retraining of authorized and affected employees is
required:
(1) Whenever there is a change in employee job
assignments;
(2) Whenever a new hazard is introduced due to a change in
machines, equipment or process;
(3) Whenever there is a change in the energy control
procedures; or
(4) Whenever a periodic inspection by the employer reveals
inadequacies in the company procedures or in the knowledge of
the employees.
5. Periodic Inspection by the Employer
a. At least annually, the employer shall ensure that an
authorized employee other than the one(s) utilizing the energy
control procedure being inspected, is required to inspect and
verify the effectiveness of the company energy control
procedures. These inspections shall at least provide for a
demonstration of the procedures and may be implemented through
random audits and planned visual observations. These inspections
are intended to ensure that the energy control
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OSHA Instruction STD 1-7.3 SEP 11 1990 Directorate of Compliance
Programs
procedures are being properly implemented and to provide an
essential check on the continued utilization of the procedures
(29 CFR 1910.147(c)(6)(i)).
(1) When lockout is used, the employer's inspection shall
include a review of the responsibilities of each authorized
employee implementing the procedure with that employee. Group
meetings between the authorized employee who is performing the
inspection and all authorized employees who implement the
procedure would constitute compliance with this
requirement.
(2) When tagout is used, the employer shall conduct this
review with each affected and authorized
employee.
(3) Energy control procedures used less frequently than once
a year need be inspected only when used.
b. The periodic inspection must provide for and ensure
effective correction of identified deficiencies (29 CFR
1910.147(c)(6)(i)(B)).
c. The employer is required to certify that the prescribed
periodic inspections have been performed (29 CFR
1910.147(c)(6)(ii)).
6. Equipment Testing or Positioning. Under 29 CFR
1910.147(f)(1), OSHA allows the temporary removal of lockout or
tagout devices and the reenergization of the machine or equipment
ONLY during the limited time necessary for the testing or
positioning of machines, equipment or components. After the
completion of the temporary reenergization, the authorized
employees shall again deenergize the equipment and resume
lockout/tagout procedures.
7. Group Lockout/Tagout. Group lockout/tagout procedures shall
be tailored to the specific industrial operation and may be unique
in the manner that employee protection from the release of
hazardous energy is
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OSHA Instruction STD 1-7.3 SEP 11 1990 Directorate of
Compliance Programs
achieved. Irrespective of the situation, the requirements of
this generic standard specify that each employee performing
maintenance or servicing activities shall be in control of
hazardous energy during his/her period of
exposure.
a. Group operations normally require that a lockout/tagout
program be implemented which ensures that each authorized
employee is protected from the unexpected release of hazardous
energy by his/her personal lockout/tagout device(s). No employee
may affix the personal lockout/tagout device of another
employee. Various group lockout/tagout procedures discussed in
Appendix C provide for each authorized employee's use of his/her
personal lockout/tagout device(s).
b. One of the most difficult problems addressed by the
standard involves the servicing and maintenance of complex
equipment. Such equipment is frequently used in the
petrochemical and chemical industries. Acceptable group
lockout/tagout procedures for complex equipment are discussed
further at Appendix C.
8. Compliance with Group Lockout/Tagout. These operations
shall, at a minimum, provide for the following:
a. Before the machine or equipment is shut down, each
authorized employee who is to be involved during the
servicing/maintenance operation shall be made aware by the
employer of the type, magnitude, and hazards related to the
energy to be controlled and of the method or means to control
the energy. In the event that the machine or equipment is
already shut down, the authorized employee shall be made aware
of these elements before beginning his/her work (29 CFR
1910.147(d)(1)). Verification shall be performed as noted at
I.8.f. of this instruction.
b. An orderly shutdown of the machine or equipment shall be
conducted which conforms to the documented company procedure and
which will not create hazards (29 CFR
1910.147(d)(2)).
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OSHA Instruction STD 1-7.3 SEP 11 1990 Directorate of Compliance
Programs
c. All energy isolating devices needed to isolate the
machine or equipment shall be effectively positioned and/or
installed (29 CFR 1910.147 (d)(3)).
d. The authorized employee(s) performing the servicing or
maintenance (following the company procedure) shall personally
affix a lock or tag upon each energy isolating device (29 CFR
1910.147(d)(4)(i). The company procedure must ensure that no
employee affixes a personal lockout/tagout device for another
employee.
(1) A single lock upon each energy isolating device,
together with the use of a lockbox for retention of the keys and
to which each authorized employee affixes his/her personal lock
or tag, also satisfies the requirement (29 CFR
1910.147(f)(3)(i)).
(2) Locks shall be affixed in a manner that will hold the
energy isolating device in a safe (off) position (29 CFR
1910.147(d)(4)(ii)).
(3) Tagout devices, where used, shall be affixed at the same
location as would a lock if such fittings are provided, or shall
be affixed in a manner that will clearly indicate that movement
of the isolating device is prohibited (29 CFR
1910.147(d)(4)(iii)).
e. Following the application of locks or tags, all
potentially hazardous stored energy or residual energy shall be
relieved, disconnected, restrained, and otherwise rendered safe
(29 CFR 1910.147(d)(5)(i)).
(1) Verification of energy isolation shall be monitored as
frequently as necessary if there is a possibility of
reaccumulation of stored energy (29 CFR
1910.147(d)(5)(ii)).
(2) Monitoring may be accomplished, for example, by
observation or with the aid of a monitoring device which will
sound an alarm if a hazardous energy level is being
approached.
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OSHA Instruction STD 1-7.3 SEP 11 1990 Directorate of
Compliance Programs
f. Authorized employees shall verify that isolation and
deenergization have been effectively accomplished before
starting servicing/maintenance work. Verification is also
necessary by each group of workers before starting work at shift
changes.
g. Release from lockout/tagout shall be accomplished in
compliance with the requirements at 29 CFR
1910.147(e).
(1) The machine or equipment area shall be cleared of
nonessential items to prevent malfunctions which could result in
employee injuries 29 CFR 1910.147(e)(1)).
(2) The authorized employees shall remove their respective
locks or tags from the energy isolating devices or from the
group lock-box(s) following the procedure established by the
company (29 CFR 1910.147(e)(3)).
(3) In all instances, the company procedure must provide a
system which identifies each authorized employee involved in the
servicing/maintenance operation.
(4) Before reenergization, all employees in the machine or
equipment area shall be safely positioned or moved from the
area, and the affected employees shall be notified that the
lockout/tagout devices have been removed (29 CFR
1910.147(e)(2)).
h. During all group lockout/tagout operations where the
release of hazardous energy is possible, each authorized
employee performing servicing or maintenance shall be protected
by his/her personal lockout or tagout device and by the company
procedure. As described at Appendix C, B.1.g., a master tag is a
personal tagout device if each employee personally signs on and
signs off on it and if the tag clearly identifies each
authorized employee who is being protected by it.
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OSHA Instruction STD 1-7.3 SEP 11 1990 Directorate of Compliance
Programs
9. Compliance of Outside Personnel. Outside servicing and
maintenance personnel (contractors, etc.) engaged in activities
regulated under 29 CFR 1910.147 are subject to the requirements of
that standard.
a. The CSHO shall verify that the outside employer and the
on-site employer have exchanged information regarding the
lockout/tagout energy control procedures used by each employer's
workers (29 CFR 1910.147(f)(2)(i)).
b. The CSHO shall verify that the on-site employer has
effectively informed his/her personnel of the restrictions and
prohibitions associated with the outside employer's energy
control procedures (29 CFR 1910.147(f)(2)(ii)).
c. When an outside employer is engaged in servicing and
maintenance activities within an on-site employer's facility and
if that contractor's activities are subject to the requirements
of 29 CFR 1910.147, the CSHO shall coordinate with the Area
Director to obtain permission to initiate an independent
inspection of the outside contractor's
activities.
10. Appendix B contains an example of a functional flow
diagram to implement safe lockout/tagout procedures. This flow
diagram is presented solely as an aid and does not constitute the
exclusive or definitive means of complying with the standard in
any particular situation.
J. Classification of Violations.
1. A deficiency in the employer's energy control program
and/or procedure that could contribute to a potential exposure
capable of producing serious physical harm or death shall be cited
as a serious violation.
2. The failure to train "authorized", "affected", and "other"
employees as required for their respective classifications should
normally be cited as a serious violation.
3. Paperwork deficiencies in lockout/tagout programs where
effective lockout/tagout work procedures are in place shall be
cited as other-than-serious.
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OSHA Instruction STD 1-7.3 SEP 11 1990 Directorate of
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K. Evaluation. In keeping with agency policy, each Region shall
evaluate the effectiveness of the guidance in this instruction
annually. Each Regional Administrator shall submit a written
evaluation report to the Directorate of Compliance Programs within
30 days of the close of the fiscal year.
Gerard F. Scannell Assistant Secretary
DISTRIBUTION: National, Regional, and Area Offices All
Compliance Officers State Designees NIOSH Regional Program Directors
7(c)(1) Consultation Project Managers OSHA Training
Institute
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OSHA Instruction STD 1-7.3 SEP 11 1990 Directorate of
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Appendix A
The following listing indicates a number of OSHA standards which
currently impose lockout/tagout related requirements. The list does
not necessarily include all lockout/tagout related OSHA 29 CFR 1910
standards.
Powered Industrial Trucks
1910.178(q)(4)
Overhead and Gantry Cranes
1910.179(g)(5)(i), (ii), (iii) 1910.179(1)(2)(i)(c),
(d)
Derricks
1910.181(f)(2)(i)(c), (d)
Woodworking Machinery
1910.213(a)(10) 1910.213(b)(5)
Mechanical Power Presses
1910.217(b)(8)(i) 1910.217(d)(9)(iv)
Forging Machines
1910.218(a)(3)(iii), (iv) 1910.218(d)(2) 1910.218(e)(1)(ii),
(iii) 1910.218(f)(1)(i), (ii), (iii) 1910.218(f)(2)(i), (ii)
1910.218(h)(2), (5) 1910.218(i)(1), (2) 1910.218(j)(1)
Welding, Cutting and Brazing
1910.252(c)(1)(i)
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OSHA Instruction STD 1-7.3 SEP 11 1990 Directorate of Compliance
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Pulp, Paper and Paperboard Mills
1910.261(b)(4) 1910.261(f)(6)(i) 1910.261(g)(15)(i)
1910.261(g)(19)(iii) 1910.261(j)(4)(iii) 1910.261(j)(5)(iii)
1910.261(k)(2)(ii)
Textiles
1910.262(c)(1) 1910.262(n)(2) 1910.262(p)(1)
1910.262(q)(2)
Bakery Equipment
1910.263(l)(3)(iii)(b), 1910.263(l)(8)(iii)
Sawmills
1910.265(c)(12)(v), 1910.265(c)(13), 1910.265(c)(26)(v)
Grain Handling
1910.272(e)(1)(ii) 1910.272(g)(1)(ii)
1910.272(l)(4)
Electrical
1910.305(j)(4)(ii)(A), 1910.305(j)(4)(ii)(c)(1)
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OSHA Instruction STD 1-7.3 SEP 11, 1990 Directorate of
Compliance Programs
Appendix B
This flow diagram does not constitute the exclusive or
definitive means of complying with the standard in any particular
situation and is presented solely as an aid. EXAMPLE - FUNCTIONAL FLOW DIAGRAM FOR IMPLEMENTATION OF
LOCKOUT/TAGOUT REQUIREMENTS
___________________________________________________________________
CONDUCT MACHINE/PROCESS DEVELOP DOCUMENTED HAZARD ANALYSIS _________
LOCKOUT/TAGOUT PROCEDURE
^ | | V
____________________| DEVELOP TRAINING PROGRAM |
__________________________ |_________________________
| V V V |PROVIDE TRAINING TO PROVIDE DETAILED TRAINING PROVIDE TRAINING
TO | AFFECTED EMPLOYEES TO AUTHORIZED EMPLOYEES ALL OTHER EMPLOYEES | | |
V | ASSIGN MAINT./SERVICE | TASK TO | AUTHORIZED EMPLOYEES | | | V |
___________________________ AND | | | | V V | CONSULT COMPANY NOTIFY
AFFECTED | PROCEDURES DOCUMENT EMPLOYEE(S) OF | | MAINT./SERVICE OPS | | |
| IDENTIFY | | ENERGY ISOLATING DEVICES | | | | IDENTIFY & OBTAIN |
|_______________
LOCKOUT/TAGOUT | DEVICES | | | V __________________________
| ___________AND/OR__________ | | | | | | V V | | DEACTIVATE &
DEACTIVATE & | | TAGOUT LOCKOUT | | |_________________________| | | |
| | V | | VERIFY HAZARDOUS | | ENERGY CONTROLLED | | | | |__ HAZARDOUS ENERGY __________ OR |
NOT CONTROLLED | |
V |
PERFORM TASK |
| |
V |
RETRIEVE TOOLS & EQUIPMENT |
| |
V |
VERIFY PERSONNEL |
CLEAR AND ACCOUNTED FOR |
| |
V |
REMOVE LOCKOUT/TAGOUT |
DEVICES |
| |
V |
NOTIFY AFFECTED |
EMPLOYEES |
| |
V |
RETURN CUSTODY OF RESTORE POWER & PROBLEM IDENTIFIED
EQUIPMENT __________ VERIFY OPS ___________
TO AFFECTED EMPLOYEE(S)
B-1
OSHA Instruction STD 1-7.3 SEP 11, 1990 Directorate of
Compliance Programs
Appendix C
This appendix provide guidelines to assist the compliance
officer during evaluations of employer operations.
A. Normal Production Operations. The lockout/tagout standard, 29
CFR 1910.147, addresses the safety of employees engaged in servicing
and maintenance activities in general industry workplaces. The
standard complements the requirements for machine and process
operator safety prescribed by the various general industry standards
in 29 CFR Part 1910. Subpart O of 29 CFR 1910 provides the
principal, though not exclusive, machine guarding
requirements.
1. Safeguarding of servicing and maintenance workers can be
ensured either by:
a. Effective machine safeguarding in compliance with Subpart
O, or
b. Compliance with 29 CFR 1910.147 in situations where the
normal production operations safeguards are rendered ineffective
or do not protect the servicing/maintenance
worker.
2. Activities which are routine, repetitive, and integral to
the use of equipment for production are not covered by this
standard if alternative measures provide effective worker
protection from hazards associated with unexpected energization.
Compliance with the machine guarding requirements of Subpart O is
an example of such alternative measures. In addition, supplemental
personal protective equipment may be necessary during a servicing
or maintenance operation when a toxic substance is to be isolated.
Under such circumstances, the requirements of applicable
standards, such as 29 CFR 1910.134 and Subpart Z, also must be
met.
3. An employer who requires employees to perform routine
maintenance and/or servicing while a machine or process is
operating in the production mode, must provide employee
safeguarding under the applicable requirements of Subpart O. (Ref.
29 CFR 1910.212(a)(1)). Operations such as lubricating, draining
sumps, servicing of filters, and inspection for leaks and/or
mechanical malfunction are examples of routine
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OSHA Instruction STD 1-7.3 SEP 11, 1990 Directorate of
Compliance Programs
operations which can be accomplished with effective
production-mode safeguards. However, the replacement of machine
or process equipment components such as valves, gauges,
linkages, support structure, etc. , is not considered to be
normal routine maintenance function which can safely be
accomplished during machine or process equipment operation. Such
maintenance requires energy isolation and should be evaluated by
OSHA field staff. They also may be an appropriate subject of a
variance request.
4. Several alternative means of safeguarding the hazardous
portions of machines and equipment are presented by the national
consensus standard, ANSI B11.19-1990. Although that standard is
not all inclusive, it describes effective safeguarding
alternatives for the protection of employees. The safeguards
describe include: interlocked barrier guards, presence sensing
devices and various devices under the exclusive control of the
employee. Such devices or guards, properly applied, may be used in
clearing minor jams and performing other minor servicing functions
which occur during normal production operations and which meet the
criteria described in paragraph A.2. of this appendix.
B. Group Lockout/Tagout. The group lockout/tagout procedures
described in this instruction at paragraph I.8. require each
authorized employee to be in control of potentially hazardous energy
release during their servicing/maintenance work assignments. Under
most circumstances, where servicing/maintenance is to be conducted
during only one shift by an individual or a small number of persons
working together, the installation of each individual's
lockout/tagout device upon each energy isolating device would not be
a burdensome procedure. However, when many energy sources or many
persons are involved, and/or the procedure is to extend over more
than one shift, (possibly several days, or weeks) consideration must
be given to the implementation of a lockout/tagout procedure that
will ensure the safety of the employees involved and will provide
for each individual's control of the energy hazards. The following
procedures are presented as examples to illustrate the
implementation of a group lockout/tagout procedure involving many
energy isolating devices and/or many servicing/maintenance
personnel. They illustrate several alternatives for having
authorized employees affix personal lockout/
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OSHA Instruction STD 1-7.3 SEP 11, 1990 Directorate of
Compliance Programs
tagout devices in a group lockout/tagout setting. These
examples are not intended to represent the only acceptable
procedures for conducting group operations.
1. Definitions. Various terms used in the examples are defined
below.
a. PRIMARY AUTHORIZED EMPLOYEE is the authorized employee
who exercises overall responsibility for adherence to the
company lockout/tagout procedure. (See 29 CFR
1910.147(f)(3)(ii)(A).)
b. PRINCIPAL AUTHORIZED EMPLOYEE is an authorized employee
who oversees or leads a group of servicing/maintenance workers
(e.g. , plumbers, carpenters, electricians, metal workers,
mechanics).
c. JOB-LOCK is a device used to ensure the continuity of
energy isolation during a multi-shift operation. It is placed
upon a lock-box. A key to the job-lock is controlled by each
assigned primary authorized employee from each
shift.
d. JOB-TAG with TAB is a special tag for tagout of energy
isolating devices during group lockout/tagout procedures. The
tab of the tag is removed for insertion into the lock-box. The
company procedure would require that the tagout job-tag cannot
be removed until the tab is rejoined to it.
e. MASTER LOCKBOX is the lockbox into which all keys and
tabs from the lockout or tagout devices securing the machine or
equipment are inserted and which would be secured by a
"job-lock" during multi-shift operations.
f. SATELLITE LOCKBOX is a secondary lockbox or lock-boxes to
which each authorized employee affixes his/her personal lock or
tag.
g. MASTER TAG is a document used as an administrative
control and accountability device. This device is normally
controlled by the operations department personnel and is a
personal tagout device if each employee personally signs on and
signs off on it and if the tag clearly identifies each
authorized employee who is being protected by it.
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OSHA Instruction STD 1-7.3 SEP 11, 1990 Directorate of
Compliance Programs
h. WORK PERMIT is a control document which authorizes
specific tasks and procedures to be accomplished.
2. Organization. A group lockout/tagout procedure might
provide the following basic organizational structure:
a. A primary authorized employee would be designated. This
employee would exercise primary responsibility for
implementation and coordination of the lockout/tagout of
hazardous energy sources, for the equipment to be
serviced.
b. The primary authorized employee would coordinate with
equipment operators before and after completion of servicing and
maintenance operations which require
lockout/tagout.
c. A verification system would be implemented to ensure the
continued isolation and deenergization of hazardous energy
sources during maintenance and servicing
operations.
d. Each authorized employee would be assured of his/her
right to verify individually that the hazardous energy has been
isolated and/or deenergized.
e. When more than one crew, craft, department, etc., is
involved, each separate group of servicing/ maintenance
personnel would be accounted for by a principal authorized
employee from each group. Each principal employee is responsible
to the primary authorized employee for maintaining
accountability of each worker in that specific group in
conformance with the company procedure. No person may sign on or
sign off for another person, or attach or remove another
person's lockout/tagout device, unless the provisions of the
exception to 29 CFR 1910.147(e)(3) are met.
3. Examples of Procedures for Group Lockout/Tagout. Examples
are presented for the various methods of lockout/tagout using
lockbox procedures. An example of an applicable method for complex
process equipment is also presented.
a. The following procedures address circumstances ranging
from a small group of servicing/
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OSHA Instruction STD 1-7.3 SEP 11, 1990 Directorate of
Compliance Programs
maintenance employees during a one-shift operation to a
comprehensive operation involving many over a longer
period.
(1) Type A. Each authorized employee places his/her personal
lock or tag upon each energy isolating device and removes it
upon departure from that assignment. Each authorized employee
verifies or observes the deenergization of the
equipment.
(2) Type B. Under a lockbox procedure, a lock or job-tag
with tab is placed upon each energy isolation device after
deenergization. The key(s) and removed tab(s) are then placed
into a lockbox. Each authorized employee assigned to the job
then affixes his/her personal lock or tag to the lockbox. As a
member of a group, each assigned authorized employee verifies
that all hazardous energy has been rendered safe. The
lockout/tagout devices cannot be removed or the energy isolating
device turned on until the appropriate key or tab is matched to
its lock or tag.
(3) Type C. After each energy isolating device is
locked/tagged out and the keys/tabs placed into a master
lockbox, each servicing/maintenance group "principal" authorized
employee places his/her personal lock or tag upon the master
lockbox. Then each principal authorized employee inserts his/her
key into a satellite lockbox to which each authorized employee
in that specific group affixes his/her personal lock or tag. As
a member of a group, each assigned authorized employee verifies
that all hazardous energy has been rendered safe. Only after the
servicing/maintenance functions of the specific subgroup have
been concluded and the personal locks or tags of the respective
employees have been removed from the satellite lockbox can the
principal authorized employee remove his/her lock from the
master lockbox.
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OSHA Instruction STD 1-7.3 SEP 11, 1990 Directorate of
Compliance Programs
(4) Type D. During operations to be conducted over more than
one shift (or even many days or weeks) a system such as
described here might be used. Single locks/tags are affixed upon
a lockbox by each authorized employee as described at Type B or
Type C above. The master lockbox is first secured with a
job-lock before subsequent locks by the principal authorized
employees are put in place on the master lockbox. The job-lock
may have multiple keys if they are in the sole possession of the
various primary authorized employees (one on each shift). As a
member of a group, each assigned authorized employee verifies
that all hazardous energy has been rendered safe. In this
manner, the security provisions of the energy control system are
maintained across shift changes while permitting reenergization
of the equipment at any appropriate time or
shift.
b. Normal group lockout/tagout procedures require the
affixing of individual lockout/tagout devices by each authorized
employee to a group lockout device, as discussed in paragraph
B.3.a. of this appendix. However, in the servicing and
maintenance of sophisticated and complex equipment, such as
process equipment in petroleum refining, petroleum production,
and chemical production, there may be a need for adaptation and
modification of normal group lockout/tagout procedures in order
to ensure the safety of the employees performing the servicing
and maintenance. To provide greater worker safety through
implementation of a more feasible system, and to accommodate the
special constraints of the standard's requirement for ensuring
employees a level of protection equivalent to that provided by
the use of a personal lockout or tagout device, an alternative
procedure may be implemented if the company documentation
justifies it. Lockout/ tagout, blanking, blocking, etc., is
often supplemented in these situations by the use of work
permits and a system of continuous worker accountability. In
evaluating whether the equipment being serviced or maintained is
so complex as to necessitate a departure from the normal group
lockout/tagout procedures (discussed
C-6
OSHA Instruction STD 1-7.3 SEP 11, 1990 Directorate of
Compliance Programs
in paragraph B.3.a.), to the use of an alternative procedure
as set forth below, the following (often occurring
simultaneously) are some of those which must be evaluated:
physical size and extent of the equipment being
serviced/maintained; the relative inaccessibility of the energy
isolating devices; the number of employees performing the
servicing/maintenance; the number of energy isolating devices to
be locked/tagged out; and the interdependence and
interrelationship of the components in the system or between
different systems.
(1) Once the equipment is shut down and the hazardous energy
has been controlled, maintenance/servicing personnel, together
with operations personnel, must verify that the isolation of the
equipment is effective. The workers may walk through the
affected work area to verify isolation. If there is a potential
for the release or reaccumulation of hazardous energy,
verification ofisolation must be continued. The
servicing/maintenance workers may further verify the
effectiveness of the isolation by the procedures that are used
in doing the work (e.g., using a bleeder valve to verify
depressurization, flange-breaking techniques, etc.). Throughout
the maintenance and/or servicing activity, operations personnel
normally maintain control of the equipment. The use of the work
permit or "master tag" system (with each employee personally
signing on and signing off the job to ensure continual employee
accountability and control), combined with verification of
hazardous energy control, work procedures, and walk-through, is
an acceptable approach to compliance with the group
lockout/tagout and shift transfer provisions of the standard.
(Note, B.1.g. of this appendix.)
(2) Specific issues related to the control of hazardous
energy in complex process equipment are described below in a
typical situation which could be found at any facility.
This
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OSHA Instruction STD 1-7.3 SEP 11, 1990 Directorate of
Compliance Programs
discussion is intended only as an example and is not
anticipated to reflect operations at any specific
facility.
(a) Complex process equipment which is scheduled for
servicing/maintenance operations is generally identified by
plant supervision. Plant supervision would issue specific work
orders regarding the operations to be
performed.
(b) In most instances where complex process equipment is
to be serviced or maintained, the process equipment operators
can be expected to conduct the shutdown procedure. This is
generally due to their in-depth knowledge of the equipment and
the need to conduct the shut-down procedure in a safe,
economic and specific sequence.
(c) The operations personnel will normally prepare the
equipment for lockout/tagout as they proceed and will identify
the locations for blanks, blocks, etc., by placing "operations
locks and/or tags" on the equipment. The operations personnel
can be expected to isolate the hazardous energy, and drain and
flush fluids from the process equipment following a standard
procedure or a specific work permit
procedure.
(d) Upon completion of shutdown, the operations personnel
would review the intended job with the servicing and
maintenance crew(s) and would ensure their full comprehension
of the energy controls necessary to conduct the servicing or
maintenance safely. During or immediately after the review of
the job, the servicing and maintenance crews would install
locks, tags and/or special isolating devices at previously
identified equipment locations following the specified work
permit procedure.
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OSHA Instruction STD 1-7.3 SEP 11, 1990 Directorate of
Compliance Programs
(e) Line openings necessary for the isolation of the
equipment would normally be permitted only by special work
permits issued by operations personnel. (Such line openings
should be monitored by operations personnel as an added safety
measure.)
(f) All of the previous steps should have been documented
by a master system of accountability and retained at the
primary equipment control station for the duration of the job.
The master system of accountability may manifest itself as a
Master Tag which is subsequently signed by all of the
maintenance/servicing workers if they fully comprehend the
details of the job and the energy isolation devices actuated
or put in place. This signing by the respective workers
further verifies that energy isolation training relative to
this operation has been conducted.
(g) After the system has been rendered safe, the
authorized employees verify energy controls as described in
B.3.b.(1) of this appendix.
(h) Specific work functions are controlled by work permits
which are issued for each shift. Each day each authorized
employee assigned must sign in on the work permit at the time
of arrival to the job and sign out at departure. Signature,
date, and time for sign-in and sign-out would be recorded and
retained by the applicable crew supervisor who upon completion
of the permit requirements would return the permit to the
operations supervisor. Work permits could extend beyond a
single shift and may subsequently be the responsibility of
several supervisors.
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OSHA Instruction STD 1-7.3 SEP 11, 1990 Directorate of
Compliance Programs
(i) Upon completion of the tasks required by the work
permit, the authorized employees' names can be signed off the
Master Tag by their supervisor once all employees have signed
off the work permit. The work permit is then attached to the
Master Tag. (Accountability of exposed workers is
maintained.)
(j) As the work is completed by the various crews, the
work permits and the accountability of personnel are
reconciled jointly by the primary authorized employee and the
operations supervisor.
(k) During the progress of the work, inspection audits are
conducted.
(l) Upon completion of all work, the equipment is returned
to the operations personnel after the maintenance and
servicing crews have removed their locks, tags, and/or special
isolating devices following the company
procedure.
(m) At this time all authorized employees who were
assigned to the tasks are again accounted for and verified to
be clear from the equipment area.
(n) After the completion of the servicing/ maintenance
work, operations personnel remove the tags originally placed
to identify energy isolation.
(o) Operations personnel then begin check-out,
verification and testing of the equipment prior to being
returned to production service.
C. It should be noted that the purpose of the lockout/tagout
standard is to reduce the likelihood of worker injuries and
fatalities during servicing/maintenance operations. Therefore, when
compliance officers inspect workplaces, they should evaluate the
potential for employee exposure to the
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OSHA Instruction STD 1-7.3 SEP 11, 1990 Directorate of
Compliance Programs
unexpected release of hazardous energy during
servicing/maintenance operations. When a hazard is noted, the
various requirements of the standard should be applied in a manner
which will result in abatement of the hazardous
circumstance.
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