DIRECTIVE NUMBER: CPL 02-00-147 EFFECTIVE DATE: 2/11/08

SUBJECT: The Control of Hazardous Energy – Enforcement Policy and Inspection 

Procedures 

 

ABSTRACT 

Purpose: This directive (manual) establishes OSHA's enforcement policy for its 

standards addressing the control of hazardous energy. It instructs OSHA 

enforcement personnel on both the agency's interpretations of those 

standards, and on the procedures for enforcing them. The application of 

this instruction will further OSHA's goal of uniform enforcement of these 

standards. However, OSHA personnel should exercise professional 

judgment consistent with their authority as appropriate when particular 

circumstances necessitate a deviation from the guidance provided in the 

instruction in order to effectuate the purposes of the Occupational Safety 

and Health Act (OSH Act), to utilize resources to effectively administer 

the OSH Act, or to ensure CSHO safety. 

This instruction is not a standard, regulation or any other type of 

substantive rule. No statement in this instruction should be construed to 

require the regulated community to adopt any practices, means, methods, 

operations, or processes beyond those which are already required by the 

OSH Act or standards and regulations promulgated under the OSH Act. 

Scope: This instruction applies OSHA-wide.

References: 1. General Industry Standards, 29 CFR Part 1910. 

 

2. Federal Register, Vol. 54, No. 169, September 1, 1989, pages 36644-

36696, Control of Hazardous Energy Sources (Lockout/Tagout), Final 

Rule, 29 CFR 1910.147. 

3. Federal Register, Vol. 55, No. 183, September 20, 1990, pages 38677-

38687, Control of Hazardous Energy Sources (Lockout/Tagout), Final 

Rule, Corrections and Technical Amendments, 29 CFR 1910.147. 
 Abstract-2

4. Federal Register, Vol. 58, No. 59, March 30, 1993, pages 16612-

16623, Control of Hazardous Energy Sources (Lockout/Tagout), Final 

Rule, Supplemental Statement of Reasons, 29 CFR 1910.147. 

5. Federal Register, Vol. 65, No. 119, June 20, 2000, pages 38302-38304, 

Control of Hazardous Energy Sources (Lockout/Tagout), Notice of the 

Availability of a Lookback Review Pursuant to the Regulatory 

Flexibility Act and Executive Order 12866. 

Cancellations: OSHA Instruction, STD 01-05-019 [STD 1-7.3], 29 CFR 1910.147, The 

Control of Hazardous Energy (Lockout/Tagout) -- Inspection Procedures 

and Interpretive Guidance, September 11, 1990.

As part of the directive revision process, OSHA has removed and archived 

interpretations from its public web-site that no longer reflect current policy 

and/or are superseded by this OSHA Instruction. 

State Impact: This instruction describes a Federal Program change for which State 

adoption is not required, but is recommended. (See Chapter 1.VII.) 

 [State Adoption Summary]

Action Offices: National, Regional, Area, and State Consultation Offices.

Originating Office: Directorate of Enforcement Programs, Office of General Industry 

 Enforcement

Contact: Directorate of Enforcement Programs (202-693-1850) 

 Office of General Industry Enforcement 

200 Constitution Avenue, N.W., N-3119 

Washington, DC 20210 

By and Under the Authority of 

Edwin G. Foulke, Jr.

Assistant Secretary 
 Abstract-3

Executive Summary

This directive (manual) provides guidance to OSHA personnel concerning the Occupational 

Safety and Health Administration’s (OSHA’s) policy, procedures, and technical interpretations 

regarding the enforcement of the Control of hazardous energy (lockout/tagout) standard, 29 CFR 

§1910.147, and other related standards. OSHA completed a look-back review of its Control of 

hazardous energy (lockout/tagout) standard, 29 CFR §1910.147, pursuant to Section 610 of the 

Regulatory Flexibility Act and Section 5 of Executive Order 12866. In response to the look-back 

review's suggestions, OSHA Instruction STD 01-05-019 [STD 1-7.3], 29 CFR 1910.147, The 

Control of Hazardous Energy (Lockout/Tagout) – Inspection Procedures and Interpretative 

Guidance (dated September 11, 1990) has been cancelled and superseded by this instruction. 

However, due to the magnitude of this review, a phased approach is planned for the revision of 

this instruction. Many of the changes contained in this revision are described below, and the 

second phase will include the incorporation of existing letters of interpretation, including 

frequently asked questions, into the manual. 

Significant Changes 

This instruction cancels the September 11, 1990 OSHA Instruction, STD 1-7.3. This manual 

provides enforcement policy and guidance for OSHA personnel performing inspection activity 

related to the control of hazardous energy. Significant modifications in this instruction include: 

• Changes in the instruction format necessitated by the OSHA Directive System (ADM 03-

00-003); 

• Addition of Compliance Officer Safety guidelines; 

• Inclusion of Citation Examples and additional guidance regarding Affirmative Defenses;

• Incorporation of compliance assistance flowcharts; 

• Inclusion of additional guidance on the minor servicing exception, specific energy control 

procedures, periodic inspections, and unexpected energization; 

• Inclusion of additional information and guidance on Alternative Methods to 

Lockout/Tagout (LOTO); 

• Inclusion of general reference material for information pertinent to hazardous energy 

control, including governmental, industry and national consensus standards; and 

• Addition of vehicle repair and maintenance standards and practices, including relevant 

Internet links, to assist employers engaged in these activities with hazardous energy 

control. 
 i

Table of Contents 

Chapter 1 BACKGROUND .................................................................................................... 1-1

I. Purpose ...................................................................................................................... 1-1 

II. Scope ......................................................................................................................... 1-1 

III. Significant Changes................................................................................................... 1-1 

IV. Cancellations ............................................................................................................. 1-1 

V. References.................................................................................................................. 1-1 

VI. Action ........................................................................................................................ 1-3 

VII. Federal Program Change ........................................................................................... 1-3 

VIII. Standard Overview .................................................................................................... 1-3 

IX. Definitions ................................................................................................................. 1-4 

A. Affected Employee.............................................................................................. 1-4 

B. Authorized Employee ......................................................................................... 1-4 

C. Capable of Being Locked Out ............................................................................ 1-5 

D. Control Reliability.............................................................................................. 1-5 

E. Controller ........................................................................................................... 1-5 

F. Disconnecting Means......................................................................................... 1-5 

G. Energized ........................................................................................................... 1-5 

H. Energy Isolating Device..................................................................................... 1-5 

I. Exclusive Control............................................................................................... 1-6 

J. Group Lockout/Tagout....................................................................................... 1-6 

K. Group Lockout/Tagout Mechanism ................................................................... 1-6 

L. Hazardous Energy .............................................................................................. 1-6 

M. Hot Tap .............................................................................................................. 1-7 

N. Isolating Switch.................................................................................................. 1-7 

O. Job Lock (“Operations or Production Lock”). ................................................... 1-7 

P. Job-Tag with a Tab............................................................................................. 1-7 

Q. Lockout............................................................................................................... 1-7 

R. Lockout Device................................................................................................... 1-8 

S. Lockbox (Master)............................................................................................... 1-8 

T. Lockbox (Satellite)............................................................................................. 1-8 

U. Machinery and Machine Guarding (29 CFR Part 1910, Subpart O).................. 1-8 

V. Master Tag ......................................................................................................... 1-8 

W. Normal Production Operations ......................................................................... 1-8 

X. Personal Tagout (Accountability) Device .......................................................... 1-8 

Y. Primary Authorized Employee........................................................................... 1-9 

Z. Principal Authorized Employee ......................................................................... 1-9 

AA. Safeguarding ...................................................................................................... 1-9 

BB. Servicing and/or maintenance.......................................................................... 1-10 

CC. Setting up.......................................................................................................... 1-10 

DD. Tagout .............................................................................................................. 1-11 

EE. Tagout device ................................................................................................... 1-11 

FF. Work Authorization Permit.............................................................................. 1-11 

X. Terminology ............................................................................................................ 1-11
 ii

Chapter 2 ENFORCEMENT POLICIES AND PROCEDURES............................................ 2-1

I. Compliance Officer Safety ........................................................................................ 2-1 

II. Inspection Guidelines ................................................................................................ 2-3 

A. Performance of Servicing or Maintenance Operations ...................................... 2-3 

B. Employer Responsibility.................................................................................... 2-3 

C. Evaluations of Compliance ................................................................................ 2-3 

D. Documentation and Screening Guidance ........................................................... 2-4 

E. Outside Personnel .............................................................................................. 2-7 

F. Compliance Assistance Flowcharts.................................................................... 2-7 

III. Citation Guidance ...................................................................................................... 2-7 

A. General ............................................................................................................... 2-7 

B. Classification of Violations.............................................................................. 2-11 

C. Citations in the Alternative .............................................................................. 2-11 

D. Citation Examples............................................................................................ 2-11 

IV. Alternative Methods and Consensus Standards....................................................... 2-15 

A. General ............................................................................................................. 2-15 

B. Minor Servicing Exception to the Lockout/Tagout Standard .......................... 2-16 

C. 29 CFR 1910, Subpart O, Machinery and Machine Guarding........................ 2-16 

D. Consensus Standards........................................................................................ 2-22 

E. Energy Isolating Device Equivalency .............................................................. 2-27 

F. Other Abatement Methods ............................................................................... 2-30 

V. Multi-employer Scenario ......................................................................................... 2-31 

VI. Affirmative Defenses............................................................................................... 2-32 

A. Greater Hazard ................................................................................................. 2-32 

B. Impossibility..................................................................................................... 2-32 

C. Unpreventable Employee Misconduct and Isolated Instance........................... 2-33

Chapter 3 INSPECTION GUIDANCE ................................................................................... 3-1

I. Purpose of the Standard............................................................................................. 3-1 

II. Scope and Application of the Standard ..................................................................... 3-2 

A. Unexpected Energization, Unexpected Start-up, and Release of Stored Energy3-2 

B. Normal Production Operations .......................................................................... 3-6 

C. Lockout/Tagout’s Relationship to Other OSHA Standards ............................... 3-8 

D. Standard Exemptions ....................................................................................... 3-16 

E. Compliance Assistance Flowcharts.................................................................. 3-17 

III. Vehicle Hazardous Energy Control ......................................................................... 3-22 

A. Background ...................................................................................................... 3-22 

B. Hazardous Energy ............................................................................................ 3-22 

C. Energy Control Program .................................................................................. 3-23 

D. Manufacturers’ Servicing and Maintenance Guidelines .................................. 3-24 

E. “Troubleshooting,” Testing, and Component Positioning ............................... 3-24 

F. References........................................................................................................ 3-25 

IV. Minor Servicing Exception to the Lockout/Tagout Standard.................................. 3-25 

V. Protective Materials and Hardware ......................................................................... 3-32 

A. Durable............................................................................................................. 3-32 

B. Standardized..................................................................................................... 3-32 
 iii

C. Substantial........................................................................................................ 3-33 

D. Labeling............................................................................................................ 3-33 

VI. Energy Isolating Devices ......................................................................................... 3-33 

A. Capable of Being Locked Out.......................................................................... 3-34 

B. Not Capable of Being Locked Out................................................................... 3-35 

VII. Lockout vs. Tagout .................................................................................................. 3-35 

A. Tagout .............................................................................................................. 3-35 

B. Lockout and Full Employee Protection [Tags Plus]........................................ 3-37 

VIII. Notification of Affected Employees........................................................................ 3-38 

IX. Energy Control Procedures...................................................................................... 3-39 

X. Application of Control Measures ............................................................................ 3-48 

XI. Removal of Lockout/Tagout Devices...................................................................... 3-53 

XII. Machine or Equipment Testing or Repositioning.................................................... 3-55 

XIII. Outside Personnel.................................................................................................... 3-56 

XIV. Group Lockout/Tagout ............................................................................................ 3-57 

XV. Shift or Personnel Changes...................................................................................... 3-58 

XVI. Employee Training .................................................................................................. 3-60 

XVII. Periodic Inspection .................................................................................................. 3-65

Chapter 4 GROUP LOCKOUT/TAGOUT ............................................................................. 4-1

I. Definitions ................................................................................................................. 4-1 

II. Background................................................................................................................ 4-1 

III. Group Lockout/Tagout: Organizational Structure..................................................... 4-2 

A. Primary Authorized Employee Designation....................................................... 4-2 

B. Primary Authorized Employee Coordination..................................................... 4-2 

C. Principal Authorized Employee Designation..................................................... 4-2 

D. Verification System............................................................................................ 4-2 

E. Authorized Employees ....................................................................................... 4-3 

IV. Group Lockout/Tagout Overview.............................................................................. 4-3 

A. Shutdown Preparation ........................................................................................ 4-4 

B. Shutdown ........................................................................................................... 4-4 

C. Affected Employee Notification ........................................................................ 4-4 

D. Isolation.............................................................................................................. 4-4 

E. Application of Lockout/Tagout Devices............................................................ 4-4 

F. Stored Energy..................................................................................................... 4-5 

G. Verification of Isolation ..................................................................................... 4-5 

H. Servicing/Maintenance....................................................................................... 4-6 

I. Release from Lockout/Tagout............................................................................ 4-6 

J. Re-energization. Energy may be restored to the machine or equipment........... 4-6 

V. Conventional Group Lockout/Tagout Procedures. .................................................... 4-7 

VI. Alternative Group Lockout/Tagout (Control and Accountability) Procedures. ...... 4-10

Chapter 5 REFERENCES ....................................................................................................... 5-1
 1-1

Chapter 1 BACKGROUND 

I. Purpose. This directive (manual) establishes OSHA's enforcement policy for its 

standards addressing the control of hazardous energy. It instructs OSHA enforcement 

personnel on both the agency's interpretations of those standards, and on the procedures 

for enforcing them. The application of this instruction will further OSHA's goal of 

uniform enforcement of these standards. However, OSHA personnel should exercise 

professional judgment consistent with their authority, as appropriate, when particular 

circumstances necessitate a deviation from the guidance provided in the instruction in 

order to effectuate the purposes of the Occupational Safety and Health Act (OSH Act), to 

utilize resources to effectively administer the OSH Act, or to ensure CSHO safety. 

This instruction is not a standard, regulation or any other type of substantive rule. No 

statement in this instruction should be construed to require the regulated community to 

adopt any practices, means, methods, operations, or processes beyond those which are 

already required by the OSH Act or standards and regulations promulgated under the 

OSH Act. 

II. Scope. This instruction applies OSHA-wide. 

III. Significant Changes. Affirmative Defenses, Compliance Officer Safety, Compliance 

Assistance Flowcharts, Vehicle Hazardous Energy Control, Relationship to Other 

Standards. 

IV. Cancellations. OSHA Instruction, STD 01-05-019 [STD 1-7.3], 29 CFR 1910.147, The 

Control of Hazardous Energy (Lockout/Tagout) -- Inspection Procedures and Interpretive 

Guidance, September 11, 1990. 

As part of the directive revision process, OSHA has removed and archived interpretations 

from its public web-site that no longer reflect current policy and/or are superseded by this 

OSHA Instruction. 

 

V. References. 

A. 29 CFR Part 1910, General Industry Standards: Control of hazardous energy 

sources (lockout/tagout), 29 CFR 1910.147; Electrical; 29 CFR 1910, Subpart S, 

including the Selection and use of work practices, 29 CFR 1910.333; Machinery 

and Machine Guarding, 29 CFR 1910, Subpart O. 

B. Federal Register, Vol. 54, No. 169, September 1, 1989, pages 36644-36690, 

Control of Hazardous Energy Sources (Lockout/Tagout), Final Rule, 29 CFR 

1910.147. 

C. Federal Register, Vol. 55, No. 183, September 20, 1990, pages 38677-38688, 

Control of Hazardous Energy Sources (Lockout/Tagout), Final Rule, Corrections 

and Technical Amendments, 29 CFR 1910.147. OSHA site lists as 38677-38688 
 1-2

D. Federal Register, Vol. 58, No. 59, March 30, 1993, pages 16612-16623, Control 

of Hazardous Energy Sources (Lockout/Tagout), Final Rule, Supplemental 

Statement of Reasons, 29 CFR 1910.147. 

E. Federal Register, Vol. 65, No. 119, June 20, 2000, pages 38302-38304, Control of 

Hazardous Energy Sources (Lockout/Tagout), Notice of the Availability of a 

Look-Back Review Pursuant to the Regulatory Flexibility Act and Executive 

Order 12866. 

F. OSHA Instruction, CPL 02-00-025 (CPL 2.25I), Scheduling System for 

Programmed Inspections, January 4, 1995. 

G. OSHA Instruction, CPL 02-00-100 (CPL 2.100), Application of the PermitRequired Confined Spaces (PRCS) Standards, 29 CFR 1910.146. 

H. OSHA Instruction, CPL 02-00-103 (CPL 2.103), Field Inspection Reference 

Manual (FIRM), September 26, 1994. 

I. OSHA Instruction, CPL 02-00-111 (CPL 2.111), Citation Policy for Paperwork 

and Written Program Requirement Violations, November 27, 1995. 

J. OSHA Instruction, CPL 02-00-124 (CPL 2-0.124), Multi-Employer Citation 

Policy, December 10, 1999 

K. OSHA Instruction, CPL 02-01-038 (CPL 2-1.38), Enforcement of the Electric 

Power Generation, Transmission, and Distribution Standard, June 18, 2003. 

L. OSHA Instruction, CPL 02-01-043, Slide-locks – Enforcement Policy, Inspection 

Procedures and Performance Guidance Criteria, September 14, 2007. 

M. OSHA Instruction, CPL 03-00-002 (CPL 2-1.35), National Emphasis Program on 

Amputations, March 26, 2002. 

N. OSHA Instruction, STD 01-12-021 (STD 1-12.21), 29 CFR 1910.217, Mechanical 

Power Presses, Clarifications, October 30, 1978. 

O. OSHA Instruction, STD 01-12-023 (STD 1-12.23), Guarding of Three-Roller 

Printing Ink Mills, July 12, 1994. 

P. OSHA Instruction, STD 01-12-024 (STD 1-12.24), Clarification and 

Interpretation of 29 CFR 1910.217, Mechanical Power Presses, as Applied to the 

Safeguarding Requirements for Die-setters, July 30, 1979. 

Q. OSHA Instruction, STD 01-16-007 (STD 1-16.7), Electrical Safety-Related Work 

Practices – Inspection Procedures and Interpretative Guidelines, July 1, 1991. 
 1-3

R. See References in Chapter 5 of this manual. 

VI. Action. Regional Administrators and Area Directors in Federal enforcement states and 

State Designees in State Plan States will ensure that the policies and procedures 

established in this instruction, or their equivalent in State Plan States, are transmitted to 

and implemented in all field offices. State Consultation Program Managers are 

encouraged to utilize this instruction during worksite evaluations. 

VII. Federal Program Change. This instruction describes a Federal program change. States 

are expected to have enforcement policies and procedures in place which are at least as 

effective as those in this instruction. 

Because of the significant nature of the policy changes contained in this instruction, 

notice of intent to adopt identical or different policies and procedures in response to this 

Instruction is required. 

 The State’s policy and procedures regarding the Lockout/Tagout standard must be 

accessible to all interested parties. Where the State’s policy differs from the Federal, 

States may either post their policy on their State Plan’s website and provide a link to 

OSHA or submit their policy to OSHA in electronic format, for posting on OSHA’s 

website. An explanation of the differences, including an indication of whether the State’s 

Lockout/Tagout standard is identical to or different from the Federal, must also be 

posted/submitted for posting. Where the State’s Lockout/Tagout policy, and standard, are 

identical, a statement to that effect with appropriate State references may be sufficient for 

posting. 

VIII. Standard Overview. The Control of Hazardous Energy (Lockout/Tagout), 29 CFR 

1910.147, standard was promulgated on September 1, 1989, at Federal Register, Volume 

54, No. 169 (pages 36644-36690), and was effective January 2, 1990, as announced at 

Federal Register, Volume 54, No. 213, November 6, 1989 (page 46610). 

A. The standard addresses practices and procedures that are necessary to disable 

machinery or equipment and to control potentially hazardous energy while 

servicing and/or maintenance activities are being performed. 

B. The standard requires that physical lockout be utilized for equipment or machines 

which have energy isolating devices capable of being locked out, except when the 

employer can demonstrate that utilization of a physical tagout system provides full 

employee protection. For equipment or machines that cannot be physically locked 

out, the employer must physically use tagout. 

C. In addition, the 1910.147 standard supplements and supports other LOTO related 

provisions in the general industry standards by establishing a requirement to 

develop complementary and uniform energy control procedures and to provide 

employee training on the procedures. The 1910.147 standard supplements and 
 1-4

augments other general industry safeguards that require the use of LOTO – e.g., 

hazardous energy control requirements contained in Subparts O and R. 

D. The standard contains definitive criteria for establishing an effective energy 

control program for the lockout or tagout of energy isolating devices. An energy 

control program includes energy control procedures, employee training, and 

periodic inspections to ensure that hazardous energy sources are isolated and 

rendered safe before and while any employee performs any servicing or 

maintenance on any machinery or piece of equipment. 

NOTE: The success of an energy control employer's program depends upon a 

commitment to the program through, in part, the development and 

implementation of: 

1. Procedures to clearly and specifically outline the necessary energy 

control steps to be taken by employees; 

2. Effective training to teach employees about the applicable 

procedure for the servicing or maintenance task to be performed; 

and 

3. Periodic inspections and other management procedures designed to 

ensure accountability. 

For additional program implementation information, see §1910.147

and the Safety and Health Management Guidelines, Issuance of 

Voluntary Guidelines (Federal Register, 54, January 26, 1989, pp. 

3904-3916) at OSHA's web-site. 

IX. Definitions. [Italicization of the term being defined indicates that the definition may be 

found in §1910.147(b). In some cases, definitions in this directive provide additional 

guidance.] 

A. 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. Affected or authorized 

employees may disable, shut down, or turn off machines or equipment. 

An affected employee becomes an authorized employee when that employee’s 

duties include performing servicing or maintenance covered under the standard. 

B. Authorized Employee. A person who locks out or tags out machines or equipment 

in order to perform servicing or maintenance on a machine or piece of equipment, 

which has a source(s) of energy that can cause injury to the employee. 

Furthermore, 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. This includes employees who: 

1) perform energy source isolation; 2) implement lockout and/or tagout on 
 1-5

machines or equipment; 3) dissipate potential (stored) energy; 4) verify energy 

isolation; 5) implement actions to release LOTO; or 6) test or position machines 

or equipment. 

 

C. Capable of Being Locked Out. An energy isolating device is capable of being 

locked out if it has a hasp or other means of attachment to which, or through 

which, a lock can be affixed, or it has a locking mechanism built into it. Other 

energy isolating devices are capable of being locked out if lockout can be 

achieved without the need to dismantle, rebuild, or replace the energy isolating 

device or permanently alter its energy control capability. Equipment that accepts 

bolted blank flanges and bolted slip blinds are considered to be capable of being 

locked out. 

D. Control Reliability. A method of ensuring the integrity of the performance of 

guards, devices, or control systems (American National Standard for Machine 

Tools – Other B11 Machine Tool Safety Standards – Performance Criteria for the 

Design, Construction, Care, and Operation, ANSI B11.19-1990). 

NOTE: The American National Standard for Machine Tools – Performance 

Criteria for Safeguarding, ANSI B11.19-2003, defines the term as 

[t]he capability of the machine control system, the safeguarding, other 

control components and related interfacing to achieve a safe state in 

the event of a failure within their safety related functions. 

 

E. Controller. A device or group of devices that serves to govern in some 

predetermined manner, the electric power delivered to the apparatus to which it is 

connected. See §1910.399. 

F. Disconnecting Means. A device, group of devices, or other means by which the 

conductor of a circuit can be disconnected from its source of supply. See 

§1910.399. 

G. Energized. Connected to an energy source or containing residual or stored energy. 

Conductors and parts of electric equipment that have been de-energized, but have 

not been locked and tagged out in accordance with §1910.333(b), must be treated 

as energized parts. Likewise, conductors and parts of electric equipment that have 

been de-energized under procedures other than those required by §§ 1910.269(d) 

or (m) and (n), as applicable, must be treated as energized. 

H. Energy Isolating Device. A mechanical device that, when utilized or activated, 

physically prevents the transmission or release of energy, including but not limited 

to the following: 

1. A manually operated electrical circuit breaker; 

2. A disconnect switch; 

3. A manually operated switch by which the conductors of a circuit can be 

disconnected from all ungrounded supply conductors, and, in addition, no pole 
 1-6

can be operated independently; 

4. A line valve, bolted blank flange and bolted slip blinds; 

5. A block (e.g., a safety block); and 

6. Any similar device used to block or isolate energy. 

Push-buttons, selector switches, safety interlocks and other control circuit type 

devices are NOT energy isolating devices. 

NOTE: Programmable logic controllers (PLCs) are used in many machine 

applications, and these control circuit 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. Refer 

to the January 25, 2008 letter to the Wm. Wrigley Jr. Company for 

additional details on PLC use with respect to the minor servicing 

exception. 

 

I. Exclusive Control. Under the exclusive control of the employee means that the 

authorized employee has the authority to and is continuously in a position to 

prevent (exclude) other individuals from re-energizing the machine or equipment 

during his servicing or maintenance activity. 

J. Group Lockout/Tagout. Group LOTO allows authorized individual employees to 

be protected from hazardous energy when they are part of a group (two or more 

employees) performing covered servicing or maintenance. Group LOTO is the 

means by which each authorized employee performing the servicing and/or 

maintenance exercises his or her control over the associated hazardous energy by 

attaching his or her personal LO or TO device onto a group LOTO mechanism. It 

consists of personal LOTO devices, group LOTO devices/mechanisms, and 

equipment LOTO devices. 

K. Group Lockout/Tagout Mechanism. Any device or mechanism that, when used as 

part of a group LOTO system, permits each individual employee to use his 

personal lockout or tagout devices to physically secure energy isolating device(s) 

during the servicing or maintenance work. The use of group lockout hasps, 

lockboxes (containing keys or tabs from equipment locks or job tags) or similar 

group mechanisms, such as a master tag that procedurally controls equipment reenergization, are examples. 

 

L. Hazardous Energy. Any energy, including mechanical (e.g., power transmission 

apparatus, counterbalances, springs, pressure, gravity), pneumatic, hydraulic, 

electrical, chemical, nuclear, and thermal (e.g., high or low temperature) energies, 

that could cause injury to employees. Danger is only present when energy may be 

released in quantities or at rates that could injure employees. 

 
 1-7

NOTE: Thermal energy may be generated as a result of electrical resistance, 

mechanical work, radiation, or chemical reaction, such as is the case 

with anhydrous ammonia, chlorine, or sulfuric acid reacting with skin, 

lung, or eye tissue causing chemical burns. 

 

Hazardous chemical energy, for purposes of this standard, includes chemicals 

(e.g., flammable and combustible liquids; flammable gases; acids and alkaline 

chemicals) that may thermally produce burn injury through high or low 

temperature. 

M. Hot Tap. A procedure used in repair, maintenance and servicing activities, which 

involves welding on a piece of equipment (pipelines, vessels or tanks) under 

pressure, in order to install connections or appurtenances. It is commonly used to 

replace or add sections of pipeline without the interruption of service for air, gas, 

water, steam, and petrochemical distribution systems. 

N. Isolating Switch. A switch intended for isolating an electric circuit from the 

source of power. It has no interrupting rating, and it is intended to be operated 

only after the circuit has been opened by some other means. See §1910.399. 

O. Job Lock (“Operations or Production Lock”). A device used to ensure the 

continuity of energy isolation during a multiple-shift operation. It is placed upon 

a lockbox. A key to the job-lock is controlled by each assigned primary 

authorized employee from each shift. 

P. Job-Tag with a Tab. A special tag that is used for the tagout of energy isolating 

devices during group LOTO procedures. The tab of the tag, for example, is 

removed for insertion into the lockbox. The company procedure would require 

that the tagout job-tag cannot be removed from the energy isolating device(s) until 

each matching tab (from the lockbox) is rejoined with its respective tag. The 

removal of the tab from the lockbox must be based on the precursory step in 

which affirmative and physical action is taken to ensure that none of the 

individual authorized employees will be exposed to hazardous energy (e.g., all 

employees remove personal locks from the lockbox). 

Q. Lockout. The placement of a lockout device on an energy isolating device, in 

accordance with an established procedure, ensuring that the energy isolating 

device and the equipment being controlled cannot be operated until the lockout 

device is removed. While the term lockout includes the placement of a lockout 

device onto an energy isolating device [as specified in §1910.147(d)(4)(i)], the 

term encompasses all systematic steps taken pursuant to an established energy 

control procedure [as specified in §1910.147(c)(4)] to shutdown the machine and 

or equipment and effectively isolate hazardous energy. 

 

NOTE: For purposes of the directive (manual), the term "LOTO" will be used 

to designate "lockout/tagout." 
 1-8

R. Lockout Device. A device that utilizes a positive means such as a lock, either key 

or combination type, to hold an energy isolating device in the safe position and 

prevent the energizing of a machine or equipment. Included are blank flanges and 

bolted slip blinds. 

S. Lockbox (Master). The lockbox into which all of the keys and/or tabs from the 

lockout or tagout devices securing the machines or equipment are inserted and 

which would be secured by individual authorized employee lockout or tagout 

devices and by a “Job-Lock” (during multi-shift operations). 

T. Lockbox (Satellite). A secondary lockbox or lockboxes to which each authorized 

employee affixes her personal lock or tag. 

U. Machinery and Machine Guarding (29 CFR Part 1910, Subpart O). See 

§1910.211 for definitions applicable to §§ 1910.213 through 1910.219. 

 

V. Master Tag. A document used as an administrative control and accountability 

device. This device is normally controlled by operations department personnel and 

is a personnel group tagout device/mechanism if each employee personally signs 

on and signs off on it and if the master tag clearly identifies each authorized 

employee who is being protected by it. 

W. Normal Production Operations. The utilization of a machine or equipment to 

perform its intended production function. The physical act or process of removing 

or releasing the isolation (e.g., opening electrical disconnects or valves), during 

the start-up process, as well as machine or equipment re-energization and/or startup, is considered a normal production operation. 

X. Personal Tagout (Accountability) Device. Any prominent warning device is 

considered a "personal tagout device" and may be used with a group LOTO 

mechanism as long as: 1) the device identifies each authorized employee being 

protected; and 2) the person in charge (principal or primary authorized employee), 

system operator, and other relevant persons can reliably ascertain the identity of 

and account for each individual who is being protected by each respective energy 

isolating device. 

Personalized tags, personal identification cards, tear-off tags, coin-like tokens, 

sign-in/sign-off logs, master tag signatures, and work authorization permit 

signatures are examples of personal accountability devices that may be used if 

they meet the above criteria. With respect to §1910.147(f)(3)(ii)(D), verbal 

accountability steps (practices) are not considered to be equivalent to each 

employee placing a personal (lockout or tagout) device on a group LOTO 

mechanism. 

NOTE: The Occupational Safety and Health Commission (OSHRC) affirmed a 

citation relating to group LOTO holding that this requirement 

mandates the use of a personal tagout device in a tagging situation 
 1-9

because the core concept of LOTO is personal protection. Verbal 

accountability methods do not afford protection equivalent to that 

provided by the implementation of a personal LOTO device. See 

Exelon Generating Corp., LaSalle County Station, OSHRC (Docket 

No. 00-1198, 2005).

Y. Primary Authorized Employee. The authorized employee who exercises overall 

responsibility for adherence to the company LOTO procedure. [See 

§1910.147(f)(3) and Chapter 4, Section III for workplace coordination and overall 

managerial procedure responsibilities.] 

Z. Principal Authorized Employee. The authorized employee who oversees or leads 

a group of servicing/maintenance employees (e.g., plumbers, carpenters, 

electricians, metal workers, mechanics). [See §1910.147(f)(3) and Chapter 4, 

Section III for workplace coordination and overall managerial procedure 

responsibilities.] 

AA. Safeguarding. ANSI B11.19-1990 national consensus standard defines 

safeguarding as the [m]ethods for protection of personnel from hazards, using 

guards, safety devices, or safe work procedures. The following ANSI B11.19-

1990 definitions describe the various types of safeguarding. 

1. Guard: A barrier that prevents entry of an individual's hand or other body 

part into the hazardous area.

2. Safeguarding device: A control or attachment that: 

a. Restrains the operator from inadvertently reaching into the hazardous 

area, or 

b. Prevents normal or hazardous operation, if any part of an individual's 

body is inadvertently within the hazardous area, or 

c. Automatically withdraws the operator's hands, if the operator's hands are 

inadvertently within the hazardous area during the hazardous portion of 

the machine cycle, or 

d. Maintains the operator or the operator's hands during the hazardous 

portion of the machine cycle at a safe distance from the hazardous area. 

NOTE: The 1990 ANSI B11.19 term Safeguarding Device was modified to 

Safeguarding (Protective) Device in the revised 2003 ANSI 

standard. The 2003 ANSI edition defines a safeguarding 

(protective) device as: 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 2a through 2d above), do not comply with the 

machine guarding provisions contained in Subpart O, when guards 

or safeguarding devices are feasible.
 1-10

3. Safe work procedures: Awareness barriers, awareness signals, shields, and 

methods are included in this safeguarding category. 

NOTE: Standing alone, safe work procedures do not constitute compliance 

with the Subpart O, Machinery and Machine Guarding, when 

guards or safeguarding devices are feasible. 

BB. Servicing and/or maintenance. 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. [In Chapters 2 through 4 of the 

manual, the term service or servicing will be used to refer to servicing and 

maintenance activities when the relevant statement applies to both servicing and 

maintenance activities.] 

NOTE: Activities where servicing and/or maintenance activities are not being 

performed on the associated machines or equipment are not covered by 

the LOTO standard. For example, some rescue activities may basically 

involve the removal of persons (e.g., elevator rescue) without any 

equipment disassembly or servicing. However, employee rescue 

activities [that do not involve a victim in an imminent danger activity, 

pursuant to §1903.13(f)] or other servicing activities that involve 

disassembly or other work on the equipment would require LOTO if 

responder exposure to hazardous energy exists. 

 Also, the standard requires employers to establish an energy control 

program to control hazardous energy that otherwise might injure or kill 

employees who service or maintain machines/equipment. However, 

the LOTO standard does not apply to equipment or machinery that is 

not the subject of the servicing and maintenance activity and that 

functions independently from, and is not a sub-system of, the 

machine/equipment being serviced or maintained. If authorized 

employees are exposed to hazardous energy associated with such an 

adjacent machine/piece of equipment while performing 

servicing/maintenance work on an independent, unrelated 

machine/piece of equipment, an employer’s obligations are established 

by Section 5(a)(1) of the OSH Act or other relevant standards, such as 

the Machine guarding (Subpart O) requirements. See The Timken 

Company (OSHRC Docket No. 97-0970, 2003). 

CC. Setting up. Any work performed to prepare a machine or equipment to perform its 

normal production operation. Setting up is not considered utilization of a machine 

or equipment and is classified as servicing and/or maintenance, rather than 

normal production operations. 
 1-11

DD. Tagout. The placement of a tagout device on an energy isolating device, in 

accordance with an established procedure, to indicate that the energy isolating 

device and the equipment being controlled may not be operated until the tagout 

device is removed. While the term tagout includes the placement of a tagout 

device onto an energy isolating device [as specified in §1910.147(d)(4)(i)], the 

term encompasses all systematic steps taken pursuant to an established energy 

control procedure [as specified in §1910.147(c)(4)] to shutdown the machine and 

or equipment and effectively isolate hazardous energy. 

 

NOTE: For purposes of the manual, the term "LOTO" will be used to 

designate "lockout/tagout." 

EE. Tagout device. A prominent warning device, such as a tag and a means of 

attachment, which can be securely fastened to an energy isolating device in 

accordance with an established procedure. The purpose of the tagout device is to 

indicate that the energy isolating device and the equipment being controlled may 

not be operated until the tagout device is removed. 

FF. Work Authorization Permit. A control document that authorizes specific tasks 

and procedures to be accomplished. 

X. Terminology. The following terms will be used in the following manner: 

A. In Chapters 2 through 4 of the manual, the term service or servicing will be used 

to refer to servicing and maintenance activities when the relevant statement 

applies to both servicing and maintenance activities. 

B. In Chapters 2 through 4, the term machines or machinery will be used to refer to 

both machines and equipment when the relevant statement applies to both 

machines and equipment. 

C. The terms he and she, as well as his or her, will be used interchangeably 

throughout the manual. References to females apply to males, and vice-versa.
 2-1

Chapter 2 ENFORCEMENT POLICIES AND PROCEDURES 

I. Compliance Officer Safety. OSHA prohibits Compliance Safety and Health Officers 

(CSHOs) from being exposed to hazards associated with the release of hazardous energy. 

CSHOs must take reasonable measures to eliminate or control exposure to hazardous 

energy when performing inspection activities. Exposure may be avoided by such 

alternative inspection techniques as: 1) interviewing employees or management 

representatives in a safe location, 2) photographing from a safe location, and 3) using 

engineering or similar drawings in lieu of obtaining direct measurements. It is of 

paramount importance that no CSHO be endangered at any time during an inspection and 

that the inspectors comply with the appropriate OSHA standards. 

Only CSHOs who are trained in energy control practices and procedures may evaluate 

machines and equipment to determine that they are properly locked and/or tagged out in 

accordance with §§ 1910.147 and 1910.333. 

NOTE: The OSHA Training Institute (OTI) currently integrates many important 

energy control principles and CSHO safety practices in various coursework, 

such as is the case with the OTI Initial Compliance Course (#1000). 

Additionally, other OTI courses (e.g., Courses #1010, #1050, #2030, #3090, 

#3094, 3095, #3190) also include electrical energy control and LOTO 

requirements in this general safety curriculum. 

 

Experienced OSHA staff may already have many OTI courses (or other 

training with equivalent curriculum) that cover the LOTO and electrical 

safety-related energy control practices; therefore, employment records and 

training certificates may be used to certify that training has been 

accomplished. 

CSHOs and their supervisors should also evaluate the inspection assignment together to 

determine whether exposure to hazardous energy may exist during the inspection process. 

This evaluation is particularly important when there are unique or complex workplace 

circumstances or when a trained CSHO has little experience with the inspection 

assignment. Furthermore, facility work areas need to be evaluated (site analysis) by the 

trained CSHO before entering such areas to determine whether there are any potential 

hazardous energy exposures. If the employer's program is not in compliance (with the 

exception of minor paperwork deficiencies that do not present an employee hazard), the 

CSHO must use alternative inspection techniques. 

 

CSHOs that perform inspection activity on employers’ machines or equipment 

undergoing servicing and/or maintenance activities are considered, by the LOTO 

standard, to be outside personnel. See §1910.147(f)(2). Prior to the performance of the 

inspection activities covered by §1910.147, CSHOs must inform the host employer of 

OSHA’s hazardous energy control procedures and safety policy (contained in this section 

and manual) and coordinate the LOTO procedures with the host employer. OSHA 
 2-2

personnel performing the inspection activity must ultimately understand the specific 

procedures to be used with the host employer. It is through strict adherence to these 

OSHA requirements, including any restrictions and prohibitions imposed by the host, that 

CSHOs must control exposures to and protect themselves from the dangers associated 

with hazardous energy. 

NOTE: Other OSHA Instructions, such as CPL 02-00-100 for the permit required 

confined spaces standard and CPL 02-01-038, for the electric power 

generation, transmission and distribution standard also address CSHO safety 

policy. 

Therefore, CSHOs must follow the LOTO standard requirements, which include the 

group LOTO and the verification of isolation provisions before inspecting, servicing and 

maintenance activities work on machinery or equipment. For example, if a CSHO 

performing a fatality investigation determines that it is necessary to inspect a potentially 

hazardous area of the bridge on an overhead crane, then the inspector would need to 

determine whether or not the employer's energy control procedure for the crane is 

compliant with the LOTO standard. The CSHO could, after determining the employer's 

procedure is compliant, then coordinate his activities with the host. This would, in part, 

entail applying his personal LOTO device on the appropriate energy isolating device(s) or 

group lockout mechanism and witnessing the verification that isolation and deenergization have been accomplished. After all of the LOTO control standard control 

measures are implemented, the CSHO may then enter the bridge area to inspect. 

NOTE: At no time shall any CSHO personally perform any machine/equipment 

shutdown, energy source isolation or servicing/maintenance work on any 

machine/equipment as part of the LOTO evaluation. All verification of energy 

isolation shall be performed by the employer's authorized or primary 

authorized employee(s) in accordance with their energy control procedures 

and witnessed by the CSHO. 

Additionally, if the overhead crane investigation scenario involves employee exposure to 

unguarded live electric circuits, such as an unguarded live electric bus, then the electric 

utilization equipment must be de-energized (e.g., lockout and tagging by a qualified 

employee) in accordance with the Selection and use of work practices, 29 CFR 

§1910.333. This standard applies to work on or near exposed energized electrical parts 

when CSHOs are close enough to expose themselves to an electrical hazard. CSHOs 

must not approach or work near any circuits and/or equipment that are not properly deenergized. 

In summary, CSHOs must use alternative inspection techniques whenever possible and 

they must not knowingly place themselves in the danger zones of any 

machines/equipment. OSHA personnel may not approach the servicing/maintenance 

work area if it is not possible to determine the zone of danger. However, CSHOs may 

implement machine LOTO if an employer's energy control program is in complete 

compliance with relevant OSHA standards, with the exception of minor paperwork 
 2-3

deficiencies that do not present an employee hazard. As part of this LOTO, OSHA 

personnel must receive the appropriate site specific training on the energy source types, 

hazards and applicable energy control and isolation procedures so as to acquire the 

requisite knowledge and skills to safely inspect the servicing/maintenance activity. 

 

OSHA Regional and Area Office policy on CSHO safety must be at least as stringent as 

the procedures stated here. 

II. Inspection Guidelines. The standard incorporates performance provisions that allow 

employers flexibility in developing LOTO programs suitable for their particular facilities 

and the particular machines being serviced. The following inspection policy provides 

guidance regarding the evaluation of an employer’s hazardous energy control program. 

A. Performance of Servicing or Maintenance Operations. The CSHO shall determine 

whether general industry servicing and maintenance operations are performed by 

employees and/or outside personnel. The CSHO shall further determine whether 

the servicing and/or maintenance operations are covered by 29 CFR §1910.147 or 

by other hazardous energy control or employee safeguarding specified by other 

standards as discussed in Section IV of this chapter. 

B. Employer Responsibility. In accordance with the grand-fathering provision of the 

standard, the employer is responsible for having isolation devices on machines or 

equipment designed to accept a lockout device. See §1910.147(c)(2)(iii) and the 

January 2, 1990 effective date. OSHA will not enforce the standard with respect 

to the designer/manufacturer of the machine or equipment, except to the extent 

that a designer/manufacturer has an obligation, as an employer, to provide 

protection for its employees as required by the LOTO standard. 

C. Evaluations of Compliance. Compliance with 29 CFR §1910.147 (LOTO) and 

related hazardous energy control standards shall be evaluated during all 

programmed and programmed-related general industry inspections where energy 

control is applicable under the focus of the inspection. The review of the records 

shall include attention to injuries related to servicing and maintenance operations. 

All programmed inspections shall be performed in accordance with the Field 

Inspection Reference Manual (the FIRM), CPL 02-00-103, and other inspection 

policies and procedures. 

For example, in order to address industries with high amputation rates and 

accomplish the Agency’s strategic goals, OSHA developed and implemented a 

National Emphasis Program on Amputations, CPL 03-00-002. Evaluations of 

compliance with the LOTO and related hazardous energy control standards shall 

be conducted as part of this national initiative to identify and reduce 

machine/equipment hazards which are causing or likely to cause amputations. 

Unprogrammed and unprogrammed-related inspections in response to alleged 

hazardous working condition involving the LOTO and related hazardous energy 

control standards shall be performed in accordance with the FIRM policy and 
 2-4

procedures. Evaluation of these standards shall be conducted whenever the 

circumstances of the unprogrammed inspection warrant (e.g., imminent dangers, 

fatalities/catastrophes, complaints, referrals) or whenever hazards involving 

hazardous energy are in plain view. 

NOTE: OSHA Instruction, STD 01-16-007, Electrical Safety-Related Work 

Practices – Inspection Procedures and Interpretative Guidelines 

(dated July 1, 1991) contains additional policy and guidance on the 

enforcement of 29 CFR §§ 1910.331 through 1910.335. These 

electrical safety-related work practices standards have provisions to 

achieve maximum safety by de-energizing energized parts and, 

secondly, when lockout and tagging is used, by ensuring that the deenergized state is maintained. Also, OSHA Instruction, CPL 02-01-

038, Enforcement of the Electric Power Generation, Transmission and 

Distribution Standard (dated June 18, 2003) contains additional policy 

and guidance for hazardous energy control practices related to 

operations and maintenance work covered by §1910.269. 

Area Directors may include these energy control compliance evaluations as part of 

an unprogrammed or unprogrammed-related inspection assignment at their 

discretion based upon prior experience or current knowledge of a particular 

establishment. Inspections under this directive may be combined, as appropriate, 

with inspections conducted pursuant to other inspection programs: e.g., National 

Emphasis Program on Amputations, CPL 03-00-002; the current Site-Specific 

Targeting (SST) program. This policy is designed to supplement and not 

supersede the FIRM (CPL 02-00-103) or any other OSHA scheduling policy or 

program. 

D. Documentation and Screening Guidance. The CSHO shall evaluate the 

employer’s compliance with the specific requirements of the standard. In the 

event deficiencies are identified, the CSHO must document non-compliance in 

accordance with established policy (per the FIRM). The following screening 

guidance, together with the interpretive policy contained in this manual, provides 

a general framework to assist the evaluator during inspections: 

1. Documentation. At a minimum, ask the employer for documentation 

including: procedures for the control of hazardous energy; certification of 

employee training; and the certification of periodic inspection. 

2. 29 CFR 1910.147(c)(4) Requirements. The CSHO must evaluate the energy 

control procedure, as required by 29 CFR §1910.147(c)(4). If the employer 

does not have a written energy control procedure, analyze the eight-point 

documentation exception, as detailed in the 29 CFR §1910.147 (c)(4)(i) note, 

to determine whether a documented energy control procedure is required. The 

results of these analyses should be placed in the inspection case file. 

Whenever possible, the CSHO should observe and evaluate actual servicing or 
 2-5

maintenance activities to determine compliance with the LOTO standard and 

the adequacy of the employer’s established procedures for the control of 

hazardous energy. Refer to additional guidance in this instruction for 

guidance and assistance in the evaluation of the employer’s energy control 

procedure(s). 

3. Training Program Evaluation. Evaluate the employer’s training program for 

“authorized,” “affected,” and “other” employees. Interview a representative 

sampling of selected employees as part of this evaluation [29 CFR 

§1910.147(c)(7)]. 

a. Evaluate the effectiveness of the training program by verifying that 

authorized employees recognize and understand: 

i. All applicable hazardous energy sources; 

ii. Type and magnitude of energy found in the workplace; 

iii. Means and methods of isolating and/or controlling energy; and 

NOTE: If the employer uses tagout devices on lockable energy 

isolating devices, CSHOs need to carefully evaluate the 

Full employee protection (Tags Plus), §1910.147(c)(3), 

provisions to determine whether the tagout program 

provides an equivalent level of safety to a lockout program. 

For additional information, refer to Chapter 3, Section VII. 

iv. Means of verification of effective energy control and the purpose of 

the procedure to be used. 

b. Verify that affected employees have been instructed in the purpose and use 

of the energy control procedure(s). 

c. Verify that all other employees who work in the area where the energy 

control procedure(s) are utilized are instructed about the procedure and the 

prohibition against attempting to restart or reenergize machines or 

equipment that is locked or tagged out. 

d. When the employer’s procedure(s) permit the use of tagout, the training of 

authorized, affected, and other employees also shall include the following 

information: 

i. Tags are essentially warning devices and do not provide the physical 

restraint on energy isolating devices that is provided by a lock; 

NOTE: Employee training on tagout system energy control methods 

must include, if relevant, the Full employee protection 

(Tags Plus) technique(s) that are being used to 

programmatically bridge the safety gap since tagout devices 
 2-6

are not equivalent to lockout devices. 

ii. When a tag is attached to an energy isolating means, it is not to be 

removed without authorization of the authorized employee responsible 

for it, and it is never to be bypassed, ignored, or otherwise defeated; 

NOTE: Employees also must receive training on the required 

procedural steps for the removal of a personal LOTO 

device, if an employer permits another employee to remove 

an authorized employee’s lockout or tagout device (as 

detailed in the §1910.147(e)(3) exception). 

iii. Tags must be legible and understandable by all authorized, affected, 

and other employees whose work operations are or may be in the area, 

in order to be effective; 

iv. Tags and their means of attachment must be made of materials that 

will withstand the environmental conditions encountered in the 

workplace; 

v. Tags may invoke a false sense of security, and their meaning needs to 

be understood as part of the overall energy control program; and 

vi. Tags must be securely attached to energy isolating devices so that they 

cannot be inadvertently or accidentally detached during use. 

4. Enforcement. Evaluate the effectiveness of the employer's enforcement of the 

energy control procedure(s). [See 29 CFR §1910.147(c)(4)(ii) and Section III

of this chapter.] 

5. Periodic Inspection Requirements. Evaluate compliance with the 

requirements for periodic inspections of energy control procedures and, if 

conducted, determine whether any deviations or inadequacies discovered by 

the inspections were corrected. The evaluation needs to determine that the 

person performing the periodic inspection is an authorized employee (other 

than the one(s) utilizing the procedure being inspected) and that these 

inspections are adequate to ascertain whether: 

a. The steps in the energy control procedure are being followed; 

b. The employees involved know their responsibilities under the procedure; 

and 

c. The procedure is adequate to provide the necessary protection and what 

changes, if any, are needed. 

6. Retraining Requirements. Evaluate the employer’s compliance with any 

retraining requirements that were identified during either the periodic 

inspection of energy control procedures or whenever the employer has reason 

to believe that there are problems with an employee's knowledge of the energy 

control procedure or with its implementation. Additionally, retraining must be 

provided for all authorized and affected employees whenever there is a change 
 2-7

in their job assignment, a change in the machines, equipment, or processes 

that presents a new hazard, or when there is a change in the energy control 

procedure. 

The CSHO shall determine whether this retraining has reestablished employee 

proficiency and whether new or revised control methods and procedures have 

been implemented. Certification of training and retraining shall be checked to 

ensure that the training included all of the elements of the energy control 

procedure which are directly relevant to the duties of the employee. 

7. Additional Lockout/Tagout Requirements. Evaluate the following LOTO 

requirements as appropriate, in accordance with the guidance provided in this 

instruction: 

a. Testing and repositioning of machines, equipment, and components 

thereof [See Section IV.A of this Chapter; Chapter 3, Section XII; and 

§1910.147 (f)(1)]; 

b. Group Lockout or Tagout [See Chapter 3, Section XIV; Chapter 4; and 

§1910.147(f)(3)]; and 

c. Shift or personnel change [See Chapter 3, Section XV and §1910.147 

(f)(4)]. 

E. Outside Personnel. When an outside employer (e.g., contractors; employees from 

a temporary employment agency) is engaged in servicing and maintenance 

activities subject to the requirements of §1910.147 within another employer’s 

facility, the CSHO should evaluate both employers’ compliance with the LOTO 

standard's requirements. [See Chapter 3, Section XIII and §1910.147(f)(2).] 

F. Compliance Assistance Flowcharts. Chapter 3 (Section II.E) contains a 

compliance assistance diagram designed to aid CSHOs in evaluating the 

effectiveness of an employer’s LOTO program. 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. 

III. Citation Guidance. 

A. General. Citations for violations of the Control of hazardous energy 

(lockout/tagout) standard shall be issued in accordance with the Field Inspection 

Reference Manual (FIRM), OSHA Instruction, CPL 02-00-103, Chapters III and 

IV. Citations alleging violations of 29 CFR §§ 1910.147(a) and (b) shall not be 

issued under any circumstances. 

Because the standard focuses on the programmatic approach to hazardous energy 

control, CSHOs are expected to carefully review the employer’s energy control 

procedure(s) and the associated documentation (e.g., hazard analyses, if 

performed; machine or equipment instructions/diagrams; training and periodic 

inspection certifications). The extent of discrepancies in the program (procedures; 
 2-8

training; periodic inspections) element documentation and implementation should 

be noted. Deficiencies in either program content or implementation may be cited, 

but the basis for any citation must be explicitly substantiated in the case file. 

On multi-employer worksites, both the host employer and outside contractors may 

be citable for a hazardous condition(s) involving §1910.147 (and other related 

standards) violations because of the flexible, performance-oriented nature of the 

standard. Host and outside (contractor) employers, depending upon the 

established energy control responsibilities (e.g., by contract or by actual practice), 

may be a creating, controlling, correcting or exposing employer. CSHOs must 

evaluate each employer’s established energy control responsibilities and 

determine whether each employer has exercised reasonable care in meeting its 

statutory obligation to comply with the OSHA standards in accordance with the 

Multi-Employer Citation Policy, CPL 02-00-124. 

NOTE: In IBP, Inc. v. Herman, 144 F.3d 861 (D.C. 1998), the Court of 

Appeals for the District of Columbia Circuit ruled that a host employer 

was not liable for the lockout/tagout violations of an independent 

contractor because, apart from pointing out the violations to the 

contractor, the host's control over those violations was limited to the 

cancellation of the contract. Proposed multi-employer citations should 

be approved through the OSHA Regional Office and the Solicitor’s 

Office. 

 

Where an employer has not established an energy control program (which consists 

of an energy control procedure, employee training, and periodic inspection), care 

must be taken (in accordance with the FIRM policy) to fairly address the 

omissions and to avoid citation duplication. An Area Director may elect to cite 

§1910.147(c)(1) for the failure to establish overall energy control program (or a 

specific program element) and also cite the individual LOTO standard 

requirements as long as the alleged deficiencies are not duplicative in nature. In 

other words, the separate requirement to establish a program is different than the 

implementation of prescribed components of that program. 

If an employer has done little or nothing to comply with the LOTO standard, 

program or program element citations for violations of the standard may be issued 

as separate items, with separate penalties. 

Additionally, Area Directors need to be aware that although some of the LOTO 

standard provisions assume that a program/procedure are in place, it is not 

appropriate for the Agency to cite provisions related to program/procedural issues 

when no program/procedure exists. For example, it would not be appropriate to 

cite an employer for failing to train employees about an energy control program 

when no such program was developed or for failing to periodically inspect energy 

control procedures when procedures -- either informally (in practice) or formally 

(documented) -- were not developed. 
 2-9

In this situation, an Area Director may cite an employer for failing to develop an 

energy control procedure, and for the failure to provide employee training on the 

knowledge and skill deficiencies associated with energy control measures for the 

machine being serviced and/or maintained -- pursuant to §§ 1910.147(c)(4)(i) and 

(c)(7)(i). 

In section (c)(4)(i) of the LOTO standard, employers are required to develop, 

document, and utilize procedures for the control of potentially hazardous energy 

and, pursuant to section (c)(4)(ii), these procedures must, in part, clearly and 

specifically: 

1. Outline the steps to be followed; 

2. Techniques to be used; and 

3. Actions to be taken by the employer to ensure that the control measures are 

utilized by employees. 

In other words, section (c)(4)(i) may be cited for procedural development, 

documentation and use issues; whereas, section (c)(4)(ii) shall be cited for 

procedural content and quality problems – e.g., for the failure to have clear and 

specific steps to be followed in order to control hazardous energy. Regardless of 

the standard cited, the alleged violation description (AVD) must identify the 

particular energy control procedure issue(s) that corresponds to the relevant 

subsection of (c)(4)(ii). For example, the AVD for a §1910.147(c)(4)(ii)(D) 

alleged violation would briefly state how the verification requirements of that 

particular standard were not met by the employer. 

The energy control procedure provisions, together with the §1910.147(d) 

Application of control requirements, contain related employer requirements for 

implementing energy control procedures. However, the regulatory text language 

of paragraph (d) refers to the requirement for the employer to have an established 

procedure; therefore, Area Directors shall not cite §§ 1910.147(d) or (d)(1) 

through (d)(6) issues if the employer does not have an established procedure. An 

employer would be considered as having an established procedure if they 

formally or informally developed or implemented energy control practices, even if 

the procedures were not in total compliance with the procedure requirements 

contained in the LOTO standard. 

NOTE: Some procedures are exempted from the procedure documentation 

requirement, so it is possible to have an established procedure that is 

not in writing, provided that each of the eight conditions is met. See 

§1910.147(c)(4)(i) note. 

In addressing the application of the energy control elements, paragraph (d) 

requires the employer to perform six LOTO system procedural actions in a 

prescribed sequence. When the violation for a single machine or piece of 
 2-10

equipment involves a failure to implement a step in an established procedure, an 

Area Director may elect to cite alleged violations individually or group 

§1910.147(c)(4)(i) for the failure to utilize the procedure and §1910.147(d) [or the 

specific subsection of paragraph (d)] in accordance with its regulatory text. 

In the event both paragraphs are cited for an implementation issue involving the 

same machine or equipment, the Area Director should normally group the 

violations into a single item. For example, a single citation may be issued for 

§1910.147(c)(4)(i) for the failure to utilize a procedure, with respect to machine 

shut down, or either §§ 1910.147(d) or 1910.147(d)(2) for the failure to shut down 

the machine in accordance with the established procedures or they may be 

grouped into a single violation item. In cases where more than one 

machine/equipment instance is documented, separate violations may be 

appropriate based on the nature of the violations. 

In other instances where an employer fails to implement more than one procedural 

element (e.g., failure to shut down a machine, failure to isolate energy, failure to 

apply LOTO devices) in accordance with the Application of control, paragraph 

(d), requirements, the Area Director may consider issuing the following 

violation(s): 

1. Cite the §1910.147(c)(4)(i) provision alleging that the established 

procedure(s) was not utilized to control hazardous energy; 

2. Cite paragraph (d) alleging that some or all of the required procedure elements 

and actions were not performed in the required sequence; 

3. Cite the first control step deficiency in the Control of application procedural 

action chronology: usually one of the steps detailed in §§ 1910.147 (d)(2) 

through (d)(6) – e.g., citing §1910.147(d)(3) failure to isolate the equipment 

from the energy source; 

4. Group the first paragraph (d) deficiency in the chronology with the subsequent 

procedural action deficiencies together as a single violation – e.g. grouping §§ 

1910.147 (d)(3) and (d)(4)(i) violations for the failure to isolate the equipment 

from the energy source and failure to apply LOTO devices to the energy 

isolating device(s). 

In instances where the energy control procedure was found to be inadequate and 

where portions of the established procedure were not adequately implemented, the 

Area Director may utilize his prosecutorial discretion and cite, as appropriate, any 

or all portions of section (c)(4) and/or paragraph (d) for the various allegations 

[e.g., section (c)(4)(ii) for specific procedure element deficiencies and paragraph 

(d) for the failure to shutdown a machine in accordance with the established 

procedure]. 

 

The above situations and citation policy do not, however, represent all of the 

possible energy control violation possibilities. LOTO violations may involve 

numerous machines and pieces of equipment, which could result in various 
 2-11

combinations and groupings of violations. Area Directors must exercise good 

judgment and discretion by citing, combining and grouping violations in 

accordance with the general principles of the FIRM. 

See Section III.D of this chapter for Citation Examples and Chapter 3, Section 

II.C for additional citation policy. 

B. Classification of Violations. Generally, a violation of 29 CFR §1910.147 could 

result in employee exposure to hazardous energy. These exposures may result in 

death or serious physical harm to employees; such violations shall normally be 

classified as serious. Paperwork deficiencies in the energy control program 

should be addressed in accordance with OSHA Instruction, CPL 02-00-111,

Citation Policy for Paperwork and Written Program Requirement Violations,

November 27, 1995. 

C. Citations in the Alternative. In cases in which it is not obvious whether the 

general industry or construction standards apply, a citation for both general 

industry and construction [e.g., §1926.64(f)(4)] violations may be issued, in the 

alternative, to address a hazardous energy control deficiency associated with the 

servicing/maintenance of a machine or piece of equipment. In other construction 

industry scenarios, a LOTO standard violation(s) may be issued “in the 

alternative” with a general duty clause [i.e., §5(a)(1) of the OSH Act] violation(s) 

in the event the Safety and Health Regulations for Construction (Part 1926) do 

not address an energy hazard associated with a specific servicing/maintenance 

activity. 

 

Additionally, there may be situations where it is not sufficiently clear whether an 

activity (e.g., machine inspection) constitutes a servicing and/or maintenance 

activity or a normal production operation (e.g., product quality control inspection). 

For example, the evidence from a fatality investigation, where the inspector was 

crushed by a product conveyor line, may be insufficient to determine definitively 

whether the employee was inspecting a conveyor line repair or simply inspecting 

product on the conveyor line. Assuming the investigation facts are legally 

sufficient, a LOTO standard violation(s) and the specific Subpart O provision(s) 

may be cited in the alternative because the employer either violated the machine 

LOTO provisions for maintenance/inspection activities or machine guarding 

provisions relating to normal production operations. 

 

D. Citation Examples. The following examples are intended for CSHO guidance 

purposes and do not reflect every situation and possibility associated with noncompliance with §1910.147 and related energy control standards. The citation 

policy contained in OSHA Instruction, CPL 02-00-103, Field Inspection 

Reference Manual (FIRM), must be followed. 

Example # 1 - A CSHO observed employees cleaning unguarded machinery 

rollers (contrary to established and documented company procedure) and these 
 2-12

employees were exposed to moving machine parts and in-going nip point 

hazards created by the operating high-speed rollers. Furthermore, the cleaning 

activity did not meet all of the elements contained in the minor servicing 

exception. This activity is a LOTO standard violation and not a machine 

guarding violation (covered by the 29 CFR §1910.212 standard) because 

cleaning is a servicing activity. 

NOTE: The applicability of 29 CFR §1910.147 versus Subpart O standards 

directly relates to the type of work activity being performed and not 

to the means of hazard abatement (i.e., LOTO versus machine 

guarding). 

The Area Director may consider issuing the following violation item(s) for this 

employee exposure to hazardous mechanical energy: 

Item #1 - 29 CFR 1910.147(c)(4)(i): Procedures were not developed, 

documented and utilized for the control of potentially hazardous energy when 

employees were engaged in the activities covered by this section: 

a) Machine #1 – The employer developed a written energy control procedure 

[include title of the procedure] for the cleaning of the machine's high speed 

rollers. However, supervisors did not enforce the energy control procedure as 

operators routinely cleaned the high speed roller during normal production 

operations. This cleaning practice exposed employees to moving machine 

parts and in-going nip point hazards created by the moving rollers. 

OR 

Item #1– 29 CFR 1910.147(d): The established procedure for the application 

of energy control (the energy control procedure) was not done in sequence as 

required by 29 CFR 1910.147(d)(1) through (d)(6): 

a) Machine #1 – Employees were exposed to machine hazards associated 

moving machine parts and in-going nip points while they cleaned unguarded, 

high speed rollers during the normal production mode of operation. The 

employer failed to implement energy control application steps as the machine 

was not shut down or turned off to perform the servicing work [per the 

1910.147(d)(2) requirements]. As a result, the remaining applicable energy 

control elements, involving machine isolation [(d)(3)], LOTO device 

application [(d)(4)], dissipation of residual energy [(d)(5)(i)], and verification 

of isolation [(d)(6)], were not implemented to protect employees from 

machine servicing hazards. 

ABATEMENT NOTE [Optional]: The machine guarding standards, in 29 

CFR 1910, Subpart O, may be used for abatement purposes provided that the 

machine guarding technique(s) (i.e., use of machine guards) that prevent 
 2-13

employee exposure to hazardous energy (e.g., in-going roller nip points). 

OR 

Item #1– 29 CFR 1910.147(d)(2): The machine or equipment was not turned 

off or shut down using the employer’s energy control procedures required by 

this standard: 

a) Machine #1 – The employer failed to shut down or turn off the machine to 

perform servicing in accordance with their established procedure, thereby 

exposing employees to the hazards of moving machine parts and in-going nip 

points while they cleaned unguarded rollers during the normal production 

mode of operation. As a result, the remaining applicable energy control 

elements, involving machine isolation [(d)(3)], LOTO device application 

[(d)(4)], stored energy [(d)(5), if applicable], and verification of isolation 

[(d)(6)], were not implemented to safeguard employees from the machine 

servicing hazards. 

ABATEMENT NOTE [Optional]: The machine guarding standards, in 29 

CFR 1910, Subpart O, may be used for abatement purposes provided that the 

machine guarding techniques (i.e., use of machine guards) that prevent 

employee exposure to hazardous energy (e.g., in-going roller nip points). 

Example # 2 - Employees unsuccessfully attempted to clean out a chemical 

process knockout pot which became inoperable due to equipment plugging 

problems. The pressurized vessel was not de-energized, pursuant to the 

established procedures, during the attempted maintenance/cleanout of the 

knockout pot. Additionally, several isolation points were not identified in the 

documented procedure. Furthermore, the procedure's methods to dissipate 

residual chemical energy and to verify that de-energization was accomplished 

were determined to be inadequate. The failure to implement these procedures 

directly resulted in the unexpected and violent release of hazardous energy 

when employees attempted to open the pressurized vessel flange. 

 

An Area Director may consider issuing the following standard violation items 

because both the company’s procedure and control actions were deemed noncompliant: 

Item #1 - 29 CFR 1910.147(c)(4)(ii): The energy control procedures did 

not clearly and specifically outline the scope, purpose, authorization, rules, 

and techniques to be utilized for the control of hazardous energy, 

including, but not limited to Items A-D of this section: 

a) Process Unit – The cleanout procedure, for the knockout pot, failed to 

clearly identify all of the specific steps to be followed by employees to 

isolate and disable the pressure vessel in order to safely de-energize the 
 2-14

equipment and control the hazardous chemical energy. The procedure also 

lacked specific steps to relieve hazardous residual chemical energy 

contained in the vessel prior to equipment opening and specific 

verification steps were not prescribed to determine the effectiveness of the 

energy control measures. 

 

ABATEMENT NOTE: The procedure must contain information which 

authorized employees must know to safely control hazardous energy. 

Overgeneralization can result in a document, which has little or no utility 

to the employee who must follow the procedure. However, while the 

procedure is required to be written in detail, this does not mean that a 

separate procedure must be written for each and every machine or piece of 

equipment. Similar machines and/or equipment (those using the same 

type and magnitude energy) that has the same or similar types of controls 

can be covered with a single procedure. 

 

AND/OR 

Item #2 - 29 CFR 1910.147(d): The established procedure for the 

application of energy control (the energy control procedures) did not cover 

the following elements or actions and was not done in sequence as 

required by 29 CFR §§ 1910.147(d)(1) through (d)(6): 

a) Process Unit - The attempted cleanout of the knockout pot and related 

piping resulted in the violent release of hazardous chemical energy 

because the company's procedure for shutdown was not followed. 

Specifically, the following control measure elements and actions were not 

sequentially performed in accordance with the established company 

procedure: 

1. Employees were not knowledgeable about the magnitude of the 

energy inside the knockout pot and the means to control of the 

energy as required by §1910.147(d)(1). For example, the various 

maintenance crews were not aware of the appropriate knockout pot 

energy isolation measures that were identified in the company's 

energy control procedure. 

2. An orderly shutdown to avoid increased hazards, as required by 

§1910.147(d)(2), was not performed because the company's 

general procedure was not completely implemented by personnel. 

Management was aware that isolation and drain valves could not 

be opened or closed per the procedure and no effort was made to 

remedy the problems so an orderly and safe shutdown could be 

accomplished. 

3. All energy isolating devices that were needed to control the 

hazardous energy for the knockout pot, as required by 
 2-15

§1910.147(d)(3), were not operated in such a manner as to isolate 

the equipment from the energy sources. Therefore, LOTO devices 

could not be affixed in accordance with §1910.147(d)(4). 

4. Residual energy was not relieved or otherwise rendered safe 

following the application of tagout devices for the knockout pot’s 

energy isolating valves in accordance with §1910.147(d)(5)(i). 

5. Prior to starting work on the knockout pot, authorized employees 

did not verify, in accordance with §1910.147(d)(6), that isolation 

and de-energization of the pressure vessel had been accomplished. 

OR 

Item #2 - 29 CFR 1910.147(d)(2): An orderly shutdown of the machine or 

equipment was not utilized to avoid any additional or increased hazard(s) 

to employees as a result of equipment de-energization: 

a) Process Unit - The attempted cleanout of the knockout pot and related 

piping resulted in the violent release of hazardous chemical energy 

because the company's procedure for shutdown was not followed. 

Specifically, an orderly and safe shut down was not performed because the 

company's energy control procedure was not implemented by personnel. 

Management was aware that isolation and drain valves could not be 

opened or closed per the procedure and no remedial action was taken to 

remedy the hazardous practice. As a result, the remaining applicable 

energy control elements, involving machine isolation [(d)(3)], LOTO 

device application [(d)(4)], stored energy [(d)(5)], and verification of 

isolation [(d)(6)], were not implemented to safeguard employees from the 

machine servicing hazards. 

IV. Alternative Methods and Consensus Standards. 

 

A. General. The LOTO standard addresses the safety of employees engaged in 

servicing and maintenance activities in general industry workplaces. The core of 

the LOTO standard, which permits employees to service and/or maintain 

machines or equipment safely, is the shutdown and de-energization of production 

process and the isolation of energy source(s). This is accomplished through the 

standard's application of hazardous energy control procedures. However, in 

promulgating the LOTO standard, OSHA did recognize circumstances in which 

discrete servicing and maintenance activities would be performed without locking 

or tagging out the machinery or equipment. 

One such circumstance is detailed in §1910.147(f)(1), which recognizes that 

LOTO devices often must be temporarily removed for discrete periods to permit

testing or positioning; however, the standard does not allow the employer or 

employee(s) to disregard the requirement for LOTO during other portions of the 
 2-16

servicing or maintenance operation. Refer to Chapter 3, Section XII for additional 

information. 

Also, the LOTO and other general industry standards (as emphasized throughout 

this OSHA Instruction) are intended to supplement each other and other methods, 

such as machine guarding, may be effective alternatives to LOTO, if the 

alternative eliminates employee exposure to the hazardous energy. 

As a general principle, the LOTO standard does not apply to servicing and 

maintenance activities when employees are not exposed to hazardous energy. 

Therefore, employees can be protected from these severe workplace injuries and 

fatality incidents by: 

1. LOTO – i.e., 29 CFR §1910.147; 

2. Complying with the minor servicing exception to the LOTO standard – 

i.e., the note contained in §1910.147(a)(2)(ii); 

3. Utilizing the cord and plug connected equipment or hot tap exemptions – 

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

4. Effective machine guarding, in compliance with Subpart O, that eliminates 

or prevents employee exposure from the hazardous energy associated with 

the machines or equipment; 

5. Final actions granting LOTO standard variances (e.g., energy isolating 

device equivalency) in accordance with the §1905 rules; or 

6. Other applicable portions of Part 1910 (e.g., guarding and LOTO 

contained in Subpart R special industries standards; electrical lockout and 

tagging requirements contained in §1910.333) that prevent employee 

exposure to hazardous energy. 

NOTE: It is important to note, however, that some types of machine guarding 

methods do not adequately protect employees from energy hazards for 

all types of servicing and maintenance work. 

 

B. Minor Servicing Exception to the Lockout/Tagout Standard. Servicing and 

maintenance activities are permitted without machine or equipment LOTO 

pursuant to the minor servicing exception -- §1910.147(a)(2)(ii) note. Minor 

servicing activities, which take place during normal production operations and 

which are routine, repetitive, and integral to the use of machine/equipment for 

production, are not covered by the LOTO standard if alternative methods provide 

effective employee protection from hazards associated with the control of 

hazardous energy (e.g., unexpected start-up). Compliance with the machine 

guarding requirements of Subpart O is an example of such alternative measures. 

Refer to Chapter 3, Section IV, for additional policy guidance. 

C. 29 CFR 1910, Subpart O, Machinery and Machine Guarding. Machine guarding 

often becomes an integral and essential component of an overall energy control 

procedure and, many times, an important economical alternative to LOTO. An 
 2-17

energy control procedure should be based upon a reliable hazard analysis that 

determines hazardous energy exposure so that hazards can be effectively 

controlled. This will provide effective employee protection during machine 

operation and component testing and positioning tasks, as well as during servicing 

and maintenance activities, and will help an employer comply with OSHA's 

performance-oriented machine guarding and LOTO standards. 

It is important to emphasize that the machine guarding requirements of 29 CFR 

Part 1910, Subpart O standards complement the requirements for LOTO. In some 

instances, an employer may avoid the requirements of the LOTO standard, if he 

eliminates exposure to servicing and maintenance hazards by using machine 

guarding techniques compliant with those standards. 

For example, the changing of dies on a full- or part-revolution mechanical power 

press requires the employer to establish a die-setting procedure that employs 

point-of-operation safeguarding method(s), such as the safe usage of an Inch or 

Jog safety device for die set-up purposes together with LOTO. See §1910.217 

(d)(9)(i). These devices safely position the mechanical power press slide utilizing 

a point-of-operation safeguarding technique. Thus, an energy control procedure 

for these types of presses would need to integrate both point-of-operation 

safeguarding method(s) for slide positioning as well as LOTO procedures for die 

setting operation -- pursuant to §1910.147(f)(1). 

NOTE: For additional guidance regarding the mechanical power press 

provisions, see §1910.217 and OSHA Instruction STD 01-12-024, 

dated July 30, 1979. Also, OSHA Instruction STD 01-12-021, dated 

October 30, 1978 provides guidance regarding the recognition of 

mechanical power press point-of-operation hazards and the definition 

of applicable machine guarding methods. 

It is also important to note that some types of machine safety devices (e.g., 

safeguarding devices) do not adequately protect employees from energy hazards 

for all types of servicing and maintenance work. For example, light curtain safety 

devices are commonly used to prevent operators from having any part of their 

body in the danger zone during the operating cycle during the machine's normal 

production mode of operation only. However, in some cases, these light curtains 

are designed such that they are not operable when a press is placed in an inch 

mode of operation. In one particular case, an amputation incident resulted from 

unexpected machine start-up because an employee incorrectly relied on a light 

curtain for his protection while he was performing servicing activities on a 

machine operating in the inch mode. 

Other safeguarding devices, such as two-hand control devices and safety mat 

devices, when properly designed and applied, safeguard machine hazard areas 

during normal production, testing, and positioning operations as they utilize 

control circuitry to prevent employees from having any part of their body in the 
 2-18

danger zone during the press's operating cycle. However, control circuit devices 

are not energy isolating devices and, as illustrated in this section, some 

safeguarding techniques (described in national consensus standards) do not 

adequately protect employees from hazardous energy exposures for all servicing 

and maintenance activities. 

The following sections provide OSHA staff with machine guarding guidance and 

additional examples: 

1. Subpart O Standards. The machine guarding standards contained in this 

subpart provide the principal, though not exclusive, machine guarding 

requirements. The following machine guarding standards (with each source 

document) apply, with limited exception, when machines are being used for 

normal production operations: 

a. §1910.212 [41 CFR §50-204.5] -- General requirements for all machines, 

b. §1910.213 [ANSI O1.1-1954 (R1961)] -- Woodworking machinery 

requirements, 

c. §1910.214 [ANSI O1.1-1954 (R1961)] -- Cooperage machinery, 

d. §1910.215 [ANSI B7.1-1970] -- Abrasive wheel machinery, 

e. §1910.216 [ANSI B28.1-1967] -- Mills and calenders in the rubber and 

plastics industries, 

f. §1910.217 [ANSI B11.1-1971] -- Mechanical power presses, 

g. §1910.218 [ANSI B24.1-1971] -- Forging machines, and 

h. §1910.219 [ANSI B15.1-1953(P1958)] -- Mechanical power-transmission 

apparatus. 

NOTE: These standards contain some servicing, maintenance and LOTO 

provisions that are intended to supplement the §1910.147 

requirements. Refer to Chapter 3, Section II.C, and 

§1910.147(a)(3)(ii) for additional information. 

The general machine guarding requirements contained in §1910.212(a)(1) are 

performance-oriented and require one or more methods of machine guarding 

to effectively protect the operator(s) and other employees in the area around 

the machine from hazards when a machine or piece of equipment is being 

used to perform its intended production function. Examples of guarding 

methods include: barrier guards, two-hand tripping devices, electronic safety 

devices, etc. Likewise, to the extent that they eliminate or prevent employee 

exposure to hazardous energy, the use of machine guarding methods (e.g., 

barrier guards, enclosure guards) may be used as alternatives to LOTO during 

servicing and/or maintenance activities. 

In terms of 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 
 2-19

reference into an OSHA standard. In the absence of such standards, the 

guarding device must be so designed and constructed so as to 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. 

NOTE: Appropriate or applicable standards, as used in the context of 

§1910.212, are references to those private consensus standards that 

were adopted and used as source standards or incorporated by 

reference in the OSHA standards. For further details, see Section 6 

of the Occupational Safety and Health Act (OSH Act) and §1910.6

for the specific standards incorporated by reference in this Part 

1910.

The remaining standards in Subpart O include definitions, machine guarding, 

and related requirements for different kinds of machinery and power 

transmission apparatus. Other OSHA standards, such as, but not limited to, 

the vertical standards for textiles, bakery equipment, and telecommunications, 

also address additional machine guarding requirements for these specific 

industries. 

2. Examples. To illustrate the relationship or complementary nature of these 

LOTO and machine guarding standards, the following brief examples are 

provided: 

a. An employer who requires employees to perform servicing and/or 

maintenance while a machine or equipment is operating in the production 

mode must provide employee protection. Operations, such as lubricating, 

draining sumps, servicing filters, making simple adjustments, and 

inspecting for leaks and/or malfunction, are examples of routine operations 

that often can be accomplished with effective production-mode machine 

guarding as addressed in Subpart O. The LOTO standard does not apply if 

employee exposure to hazardous energy is eliminated through compliance 

with the Subpart O, machine guarding, requirements. 

In contrast, the replacement of machine or process equipment components

such as valves, gauges, linkages or support structure is not considered a 

normal routine maintenance function that can be safely accomplished 

during machine or equipment operation. Such maintenance requires 

LOTO. 

b. The changing of dies on a hydraulic power press involves a sequence of 

steps that, in part, position the press slide, remove and secure dies for die 

changing purposes. In order to provide optimum employee protection, the 

LOTO standard works in conjunction with the machine guarding (Subpart 

O) standards. Compliance with Subpart O, such as using an inch safety 
 2-20

device, is required during power press test/positioning activities. 

 However, the use of an inch mechanism, for hydraulic power press die-set 

energy control steps does not effectively and reliably control all hazardous 

energy exposures to die-setters when their body parts are in, on, or in close 

proximity to hazardous energy associated with the press. Prior to placing 

their hands in, on or in close proximity to the potentially hazardous area, 

employees must, in accordance with the LOTO standard, disable and 

isolate the working area of the press as an integral step in the overall press 

energy control procedure. 

 For example, if employees need to place their hands/arms in the press 

working area (the space between the bolster plate and the ram/slide) to 

perform the servicing and/or maintenance activity (such as adjusting, 

cleaning or repairing dies), then additional energy control precautions 

(e.g., using properly applied safety blocks or slide-lock system; LOTO the 

press disconnect switch if re-energization presents a hazard) will be 

necessary because the inch or jog safety device will not protect employees 

from ram movement due to potential mechanical energy (resultant from 

the ram/slide position and associated gravitational force), press component 

or control system malfunction, or press activation by others. Refer to the 

April 22, 2005, letter to Lockton Companies of St. Louis and OSHA 

Instruction CPL 02-01-043 on slide locks for additional details. 

NOTE: The installation and removal of dies involves potential 

hazardous situations for die-setter employees because a 

trapping space exists between the top die (when the die shoes 

are together) and face of the slide or, in some instances, the 

space between the dies (if the die shoes are fastened to the 

bolster plate and slide). However, during the securing and 

unfastening of dies, the slide (with the die shoes together) is 

usually in the lowest (180 degree) position. Die-setter injury 

may still result from the sudden dropping of the upper die shoe 

when freed from the slide (due to incomplete or inadequate 

shoe attachment to the slide) if an energized inch control is 

activated (e.g., due to human error; by dropping a part onto an 

unguarded foot control treadle). 

c. Inch and jog devices have been included in the design of machines or 

equipment used by the printing (printing presses), textile (e.g., looms), and

metal stamping (e.g., power presses) industries in order to safely perform 

set-up and to address maintenance problems associated with the 

straightening or feeding of material through their processes. The use of 

properly designed and applied control circuitry (such as the use of twohand activation controls that are designed to control reliability standards 

and are mounted at a predetermined safety distance from the danger zone) 
 2-21

for the testing or positioning of machine/equipment components, in 

conjunction with LOTO, prevent employee exposure to the hazard 

associated with the movement of machine/equipment components. See 

§1910.147(f)(1). These control methods protect employees through 

compliance with Subpart O and the LOTO standards. 

d. In the printing industry, some make-ready activities on energized presses 

are performed through the use of barrier guarding (compliant with Subpart 

O) to protect employees from in-going point hazards associated with the 

press rollers. This machine guarding technique is a feasible alternative to 

LOTO as the roller guard eliminates exposure to hazardous energy 

protecting employees from the energy hazards associated with presses 

servicing and/or maintenance activities. 

 Furthermore, some operations, such as blanket-cleaning, are performed on 

printing presses while the machine is operated in a "slow run" mode. In 

this mode, barrier guards that fully extend across the entire smooth surface 

of the rolls and meet the requirements of Subpart O, protect employees 

from all ingoing nip and other machine hazards, eliminating the potential 

for employee exposure. Refer to the April 7, 2004 letter to Printing 

Industries of America, Inc. for details. 

e. In a similar situation as above, a nip point guard may be used to guard the 

ingoing nip point hazard on a three-roller printing ink mill during the 

wash-up operation. The cleaning task is, by definition, a Servicing and/or 

maintenance activity, and the equipment must be LOTO to protect the 

operator from hazardous (mechanical ) energy. However, this machine 

guarding technique may be alternatively used in lieu of LOTO if the nip 

point guard effectively prevents the cleaning cloth from getting in between 

the rollers and possibly drawing in the operator's fingers or hand into the 

danger zone. See OSHA Instruction STD 01-12-023, dated July 12, 1994, 

for additional enforcement guidance. 

f. Knife blades on a trimmer unit in a binding and finishing production line

had to be changed on a monthly basis – a non-routine set-up activity that 

does not occur during the normal production operations. Based on the 

hazard analysis, it is feasible to change the blade in accordance with the 

LOTO requirements and to utilize both the energy control procedures and 

supplemental employee protection during the blade adjustment portion of 

the task by using a plexi-glass machine guard. The transparent guard 

enables the operator to safely adjust and test the blades using a handcrank-wheel mechanism when the machine must be energized. The use of 

this barrier guard (compliant with Subpart O), in conjunction with the 

LOTO standard's positioning provisions, contained in paragraph 

1910.147(f)(1), provide optimum employee protection during this 

potentially hazardous set-up activity. Refer to the April 7, 2004 letter to 
 2-22

Printing Industries of America, Inc. for details. 

g. In a machine shop, milling machine normal production operations are 

covered by Subpart O machine guarding requirements and the LOTO 

standard does not apply if the guarding method eliminates exposure by 

physically keeping the employee’s body away from the point of operation 

and other hazardous areas of the machine. Refer to Chapter 3, Section IV

for additional guidance on milling machine minor servicing activities. 

Other practices, such as reaching around guards during press roller cleaning or 

conveyor un-jamming while the equipment is energized, are examples of 

servicing and/or maintenance activities that expose employees to hazardous 

mechanical energy. Under no circumstances is any part of an employee’s 

body ever permitted to be exposed within a hazardous area, such as the pointof-operation or in-going nip point area, during servicing and/or maintenance 

activities while the machine is running or energized. 

NOTE: For purposes of this standard, employees working on energized 

machines or equipment that meet each and every element of the 

minor servicing exception criteria (including the utilization of 

measures which provide effective protection) contained in 

§1910.147(a)(2)(ii), are not considered to be exposed to a 

hazardous area. 

D. Consensus Standards. OSHA recognizes the valuable contributions of national 

consensus standards, and in many respects, these standards offer useful guidance 

for employers and employees attempting to control hazardous energy. However, 

the OSH Act contemplates a distinction between the national consensus standard 

process and the process of OSHA rulemaking. While the former often produces 

information useful in the latter, it is not automatically equivalent. 

Section 5(a)(2) of the Act requires employers to comply with occupational safety 

and health standards promulgated under this Act. See 29 U.S.C. § 654(a)(2). As 

explained in this discussion, an employer does not necessarily satisfy its duty 

under §5(a)(2) of the Act by complying with a private standard if the private 

standard has not been adopted as or incorporated by reference into an OSHA 

standard pursuant to Section 6 of the OSH Act. 

While requiring employers to comply with OSHA standards, the OSH Act also 

authorizes OSHA to treat certain violations, which have no direct or immediate 

relationship to safety and health, as de minimis, requiring no penalty or 

abatement. See 29 U.S.C. §§ 654(a)(2) and 658(a). OSHA's enforcement policy 

provides that a violation may be de minimis, if an employer complies with a 

proposed standard or amendment or a consensus standard rather than the standard 

in effect at the time of inspection and if the employer's action clearly provides 

equal or greater employee protection. See OSHA Instruction CPL 02-00-103,
 2-23

Field Inspection Reference Manual, Chapter III, Paragraph C(2)(g), September 26, 

1994. In applying this principle, OSHA takes heed of its rulemaking findings. 

The following relevant national consensus standard descriptions address the 

control of hazardous energy and recognized machine safeguarding performance 

requirements and OSHA's related enforcement policy: 

1. Control of Hazardous Energy – Lockout/Tagout And Alternative Methods, 

ANSI Z244.1-2003. This consensus standard on LOTO and alternative 

methods offers useful guidance for employers and employees attempting to 

control hazardous energy. However, OSHA has not determined that, in all 

cases, compliance with specific provisions of the ANSI Z244.1-2003 Standard

and its annexes would constitute compliance with the relevant OSHA 

standards. 

To a considerable extent, the OSHA Lockout/Tagout Standard is a 

performance standard, which establishes general employer obligations, but 

leaves employers latitude to develop and implement specific methods for 

meeting those obligations. Where this is the case, the detailed discussion in 

the ANSI Z244.1-2003 Standard often can assist employers in developing 

specific methods to meet their obligations under the OSHA Lockout/Tagout 

Standard. 

For example, the OSHA Lockout/Tagout Standard establishes specific 

minimum criteria relevant to all energy control procedures. In Annex C, the 

ANSI Z244.1-2003 Standard details a sample energy control procedure for a 

blasting cabinet and dust extractor. While OSHA cannot ascertain whether the 

sample procedure provides the breadth and specificity mandated in 

§1910.147(c)(4)(ii) without more information about the actual machinery and 

the manner in which servicing and maintenance would be performed, this 

sample procedure may provide valuable conceptual assistance to an employer 

who is developing energy control procedures specific to its 

machinery/equipment as prescribed by the OSHA Lockout/Tagout Standard. 

 

In addition, the sample lockout/tagout placards in Annex D are good examples 

of supplemental tools that provide critical information specific to particular 

machines and equipment. An employer who chooses to develop a single, 

generic energy control procedure can supplement its generic procedure with 

similar placards to comply with 29 CFR 1910.147(c)(4)(ii). 

OSHA has not comprehensively compared each provision of the ANSI 

Z244.1-2003 Standard with the parallel provisions in OSHA standards. 

However, in several important respects, the ANSI standard appears to sanction 

practices that may provide less employee protection than that provided by 

compliance with the relevant OSHA provisions. For example, the consensus 

standard employs a decision matrix that allows employers to use alternative 
 2-24

protective methods in situations where OSHA standards require the 

implementation of machine guarding or lockout/tagout. 

In addition, the ANSI standard permits the use of tagout programs if they 

provide effective employee protection, while the OSHA Lockout/Tagout 

Standard allows the use of a tagout program only where the employer 

demonstrates it provides Full employee protection -- i.e., a level of safety 

equivalent to that obtained by using a lockout program. Further, the 

Hazardous energy control procedures, Communication and training, and

Program review sections of the ANSI Standard, while detailed and 

conceptually valuable, do not appear to mandate certain discrete practices that 

are prescribed in parallel sections of OSHA’s Lockout/Tagout Standard. 

When an OSHA standard prescribes a practice, design, or method that 

provides a requisite level of employee protection, employers may not adopt an 

alternative approach that provides a lesser level of employee protection. See 

29 U.S.C. §§ 654(a)(2) and 655 (respectively requiring employers to comply 

with occupational safety and health standards promulgated under the OSH Act 

and providing the Secretary of Labor with authority to promulgate, modify or 

revoke OSH Act occupational safety and health standards). 

2. Safeguarding When Referenced by the Other B11 Machine Tool Safety 

Standards – Performance Criteria for the Design, Construction, Care, and 

Operation – ANSI B11.19-1990. The purpose of this national consensus 

standard is to establish the performance requirements for the design, 

construction, care, and operation of safeguarding used to protect operators and 

others from machine tool hazards.

NOTE: Safeguarding, was defined in this 1990 standard, as [m]ethods for 

protection of personnel from hazards, using guards, safety devices, 

or safe work procedures. These safeguards may or may not protect 

employees adequately from all types of hazardous energy 

associated with servicing or maintaining a particular machine or 

piece of equipment. For example, if an employee needs to place 

their hands/arms in a part revolution mechanical power press 

working area to perform the repair or cleaning activity, then 

additional energy control precautions will be necessary because the 

two-hand control safeguarding device will not protect employees 

from ram movement due to potential mechanical energy (resultant 

from the ram/slide position due to gravitational force), press 

component malfunction, or press activation by others. 

Safeguarding devices (e.g., presence-sensing safeguarding devices) 

that rely on control circuitry and are used for employee protection 

purposes may not be used in lieu of LOTO during machine 

servicing/maintenance activities because control circuit devices are 
 2-25

not, by definition, energy isolating devices. See §1910.147(b). 

As a result of a legal settlement with the National Association of 

Manufacturers (NAM), OSHA incorporated a reference to this particular 1990 

consensus standard into the Normal Production Operations section (Appendix 

C, Section A) of OSHA Instruction, STD 1-7.3, 29 CFR 1910.147, The 

Control of Hazardous Energy (Lockout/Tagout) -- Inspection Procedures and 

Interpretive Guidance, dated September 11, 1990 (cancelled).

NOTE: The intent of the ANSI B11.19-1990 national consensus standard is 

to provide performance criteria for the safeguarding chosen by the 

user as referenced in the other B11 safety standards. However, the 

selection and use of properly applied B11 safeguarding for 

machines, which fall outside the scope of the B11 machine tools 

standards, may provide employers with valuable concepts and 

techniques that prevent employee exposure to hazards. 

This appendix provided guidelines to assist Compliance Safety and Health 

Officers (CSHOs) during evaluations of employer operations, and the 1990 

edition of this ANSI B11.19 consensus standard is referenced with regard to

minor servicing activities. 

Pursuant to the note for the Exception to paragraph (a)(2)(ii), Appendix C of 

OSHA Instruction STD 1-7.3 specified that the ANSI B11.19-1990 criteria 

provide [s]everal alternative means of safeguarding the hazardous portions of 

machines and equipment and that, when properly applied, may be used as 

alternative measures that provide effective protection. Although the standard 

is not all inclusive, it describes effective safeguarding alternatives for the 

protection of employees. Some described safeguards include: interlocked 

barrier guards; presence sensing devices; and various devices under the 

exclusive control of the employee. Refer to Chapter 3, Section IV, for 

additional policy guidance for this exception. 

This machine tools consensus standard was revised, reissued in 2003, and renamed as the American National Standard for Machine Tools - Performance 

Criteria for Safeguarding -- ANSI B11.19-2003. This national consensus 

standard contains requirements for the design, construction, installation, 

operation, and maintenance of the safeguarding for machine tools. The types 

of safeguarding methods contained in ANSI B11.19-2003 include: 1) guards, 

2) safeguarding devices, 3) awareness devices, 4) safeguarding (work) 

methods, and 5) safe work procedures. 

In terms of machine guarding methods (barrier guards, safety devices) and 

compliance with Subpart O, the guarding method, where feasible, must be a 

well designed and constructed guard or device that prevents employee 

exposure to the hazardous machine area or danger zone. See §1910.212(a). 
 2-26

The following ANSI B11.19-1990 safeguarding techniques are compliant with 

the OSHA Subpart O requirements, for normal production operations, as they 

either: 1) prevent employees from placing their hands or body parts into the 

hazardous machine area; or 2) prevent or stop hazardous motion of the 

machine tool, if the employee is exposed to the hazard; or 3) withdraw the 

operator's hands or body parts before a hazard exists: 

a. Barrier guards: fixed, adjustable, and interlocked; 

b. Automatic movable barrier devices; 

c. Two-hand operating lever, trip and control devices; 

d. Single control safeguarding devices; 

e. Presence-sensing safeguarding devices: electro-optical, RF, and area 

scanning; 

f. Pull back (pull out) and restraint devices; 

g. Safety mat devices. 

As previously stated, caution must be exercised as machine safeguarding 

methods may not be acceptable alternatives to LOTO if they do not eliminate 

or prevent employee exposure to energy hazards during the servicing and 

maintenance work. In terms of machine normal production operations, OSHA 

will consider adherence with the requirements for the first two categories of 

safeguarding methods, listed in the ANSI B11.19-1990 standard, for guards 

and the above listed safeguarding devices, as being primary safeguarding 

methods compliant with Subpart O. The feasibility determination as to which 

safeguarding application is appropriate is made with respect to the energy 

hazards associated with a particular servicing or maintenance task on a 

machine-by-machine basis. 

The three other ANSI B11.19 safeguarding methods (awareness devices, 

safeguarding (work) methods, safe work procedures), included in the 2003 

standard, provide a lesser degree of employee protection and are considered to 

be secondary control measures during normal production operations. These 

methods, by design, do not prevent employees from placing or having any part 

of their bodies in the hazardous machine areas. Additionally, safeguarding 

devices, such as probe detection devices and safety edge devices (aka bump 

switches) provide a lesser degree of (secondary) protection as they do not, in 

all cases, eliminate employee exposure to injury from the machine hazardous 

energy. 

Secondary control measures, which provide less employee protection, are 

acceptable and compliant with the Subpart O requirements only when the 

primary machine guarding methods (barrier guards, safety devices) cannot be 

installed due to reasons of impossibility or greater hazard. [See Section VI of 

this chapter on affirmative defenses for additional details.] Where it is 

feasible to employ the primary safeguarding methods, secondary control 

methods may supplement the primary controls; however, these secondary 
 2-27

measures must not be used in lieu of machine guarding methods required by 

Subpart O. 

NOTE: Section 12 of the ANSI B11.19-2003 standard does not classify 

complimentary equipment (e.g., work-holding equipment; hand 

tools; stop and emergency stop devices) as safeguarding devices 

because they do not prevent or detect inadvertent access to a 

hazard. The use of complimentary equipment is vital to hazard 

mitigation, but the sole use of this equipment does not constitute 

compliance with the Subpart O requirements. 

The employer has the burden to show that it is impossible to use any of the 

primary safeguarding methods (or that the safeguarding presents a greater 

hazard); however, CSHOs should include information useful to refute possible 

affirmative defenses in their case file documentation. See Section VI of this 

Chapter for additional information on affirmative defenses. 

E. Energy Isolating Device Equivalency. Paragraph 1910.147(c)(1) requires that 

before any employee performs servicing or maintenance on a machine or 

equipment where the unexpected energizing, start-up, or release of stored energy 

could occur and cause injury, the machine or equipment shall be isolated from the 

energy source, and rendered inoperative. Machines and equipment are isolated 

from energy sources by energy isolating devices. The standard prohibits the use 

of push buttons, selector switches, and other control circuit type devices as energy 

isolating devices. Thus, pursuant to the standard, such mechanisms cannot be 

used to control hazardous energy. See the definitions for Energy isolating device 

and Controller contained in Chapter 1, Section IX. 

The following electric circuit illustration consists of power and control circuits. 

The motor system, in this example, consists of a power circuit which distributes 

power (electric energy) from the source (main disconnect) to the motor (connected 

load) and a control circuit to control the distribution of power through the use of a 

motor controller (motor contactor), system interlock device, on/off key switch, 

and start/stop push buttons. 
 2-28

MOTOR 

CONTACTOR

MAIN 

DISCONNECT 

SWITCH 

 MOTOR 

(CONNECTED LOAD) 

 Power Circuit Wiring and Equipment Control Circuit Wiring and Equipment 

 

 

Motor system components may be, in practice, hundreds of feet apart from each 

other. Thus, the electrical enclosures and conduit may also be subjected to and 

affected by physical damage, vibration and potentially corrosive and invasive 

environments. 

The following case studies illustrate the reasons why LOTO of a power circuit is 

significantly safer and more reliable than control circuit protective measures: 

1. Case #1: Locking of a Push Button: Some employers rely on this control 

circuit protective method (e.g., by placing a lockable cover over a controller's 

stop/start button; tagging the control panel) to provide employee protection. 

However, the following seven (7) situations can cause unexpected motor 

energization or startup if this control circuit method is used: 

 

a. Another employee enters the motor controller (motor starter) enclosure 

and manually closes the relay; 

b. A malfunction of the push button; 

c. A relay or motor controller failure (e.g., defective spring; welded 

contacts). For example, a machine jam occurs causing higher current in the 

motor circuit, resulting in the freeze-up of the controller relay contact parts 

because the current creates arcing, which in turn welds shut the relay's 

plunger-coil mechanism. This could be particularly hazardous if an 

employee is relying on control circuits to clear jams as the energized 

machine could start up and injure the employee; 

INTERLOCK 

SWITCH 

 Control 

 Circuitry 

Energy Flow 

ON – OFF 

KEY SWITCH 

START/STOP 

PUSH BUTTONS 
 2-29

 d. A loose wire contacts the conduit or enclosure; 

 e. Two wires short out inside a damaged conduit (e.g., vibration causes wires 

to rub and wear through the wire’s insulation resulting in an electric short 

and bridging of the control circuit); 

f. Water, dirt, metal particles or other conductive foreign debris enters the 

control circuit enclosure causing the switch to operate because the material 

sufficiently bridges and closes the circuit, allowing current flow; or 

g. Ice, grease, dirt, wood, metal particles or other debris causes a push type 

control mechanism to stick in the closed position, allowing current to flow. 

Thus, OSHA has determined locking (and/or tagging) the push button for a 

control circuit is not as safe as the LOTO of a power circuit energy isolating 

(disconnect) device. 

2. Case #2: Trusting the Limit Switch: Limit switches stop a motor when you 

operate a gate or remove a guard on a machine or piece of equipment. These 

devices prevent push buttons from energizing the circuit, but they will not 

prevent the motor from starting if any voltage is present in the power circuit. 

A motor can start regardless of what is done in the control circuit, and a motor 

can be started in at least the following ways: 

 a. Closing the relay or motor controller (motor starter); 

 b. Shorting out the wiring in the conduit/enclosure; or 

 c. Shorting out the wire against the conduit/enclosure. 

These case studies identify just some of the shortcomings and associated hazards 

of relying on control circuitry as a primary method to control hazardous energy. A 

switch or other device in a control circuit is not an energy isolating device and 

interrupting the power circuit at the motor isolating (disconnect) switch is the 

safest and most reliable way to control energy associated with the motor. 

NOTE: The Cincinnati Technical Center (CTC) developed a demonstration 

tool to illustrate the servicing and maintenance hazards associated with 

only locking or tagging out a control circuit. The demonstration panel 

and instruction is available for internal OSHA training and education 

purposes through the CTC's Agency Loan Equipment Program 

(ALEP). Information about this ALEP may be found on the OSHA 

intranet under the Directorate of Science, Technology & Medicine's 

Cincinnati Technical Center's web-page. 

However, there will be times when an exception to LOTO will be permitted, for 

discrete periods, due to the need for the employer to have the power circuit 

energized. In a limited minor servicing exception, contained in the 

§1910.147(a)(2)(ii) note, an employer must still provide effective alternative 

protection in lieu of energy isolation. Also, OSHA allows the removal of LOTO 

devices, in accordance with the sequence of actions specified in §1910.147(f)(1), 
 2-30

when there is a need to test or position the machine, equipment or system 

components. Employers must provide effective protection from the hazardous 

energy during the time that it takes to complete this temporary measure for a 

particular system test or positioning task. See also Section IV.B of this chapter 

and Chapter 3, Sections IV and XII for additional guidance. 

Additionally, OSHA issued a January 5, 1998, letter of interpretation to the 

Procter and Gamble Company which accepted their specific safety disconnect 

system (inherently fail-safe system) as equivalent to an energy isolating device. 

The equivalency determination was based upon the specific process machine facts 

and a failure analysis report that concluded that their inherently fail-safe system 

reliably prevented wired load circuits to (functionally interconnected) process 

machines from being energized by an electrical source. Thus, the Procter and 

Gamble Company's fail-safe disconnect system must be used in accordance with 

all design parameters, instructions, and limitations contained in the original report. 

Although this thorough system design review demonstrated equivalency, the 

variance procedures [pursuant to 29 CFR §1905] must be followed for future 

determinations, based on a case-by-case analysis, because control circuitry is 

explicitly rejected in the standard’s definition of an energy isolating device. In the 

event that an employer elects to apply for a variance for the use of control 

circuitry in lieu of an energy isolating device for work that does not fall within the 

minor servicing exception, the employer may contact the: 

Office of Technical Programs and Coordination Activities 

200 Constitution Avenue, NW, Room N-3655 

Washington, DC 20210 

202-693-2110. 

F. Other Abatement Methods. Sometimes employees are performing servicing 

and/or maintenance work where other preventive measures would adequately 

protect them from exposure to hazardous energy. As previously described, 

§1910.147 applies in these situations; however, the application of alternative 

means of abatement eliminates the need for disabling machines or equipment and 

implementing an energy control procedure. For example, one employer had 

maintenance employees clean an open top-mixing vat that contained a “screwlike” cutting blade. The employees accessed and cleaned the equipment through 

the use of an unguarded catwalk that was located above the vat. Tragically, a 

cleaning employee fell into the vat during the cleaning process. 

In this instance, one means to prevent exposure, would be the installation of a 

standard catwalk guardrail system in accordance with the Walking and Working 

Surfaces, Subpart D requirements. This example illustrates how a single 

abatement measure (alternative protective method) would keep employees’ bodies 

out of the danger zones, thus negating the need for energy control requirements 
 2-31

since the employees no longer could be exposed to hazardous energy. Obviously, 

if the employees are required to bypass the standard guardrail system or otherwise 

expose themselves to the hazardous energy (in this case the revolving cutting 

blade), then the LOTO standard requirements must to be implemented. 

In another example, dry-cleaning employees disassembled machines that 

contained steam-heated components, which posed serious thermal energy (burn) 

hazards. The LOTO standard applies because the thermal energy may injure 

employees. 

V. Multi-employer Scenario. A contractor employer performing maintenance work on a 

boiler pipeline fails to verify that all of the residual energy in the line has been safely 

relieved because she believes the host employer effectively de-energized the unit. The 

contractor employees are injured as a result of opening the flange, and the contractor 

blames the host employer for its failure to adequately control the hazardous energy. 

The CSHO needs to thoroughly document the facts, in the case file, to determine whether 

the §1910.147(f)(2) outside personnel provisions were met and to determine whether the 

agreed upon energy control responsibilities (e.g., contractual responsibilities) of each 

party were met. Both the host and contractor employers have independent obligations to 

provide protection under this performance-oriented standard for their respective 

employees. In this scenario, the CSHO should determine which employer(s) had the 

responsibility to verify energy isolation based upon each employer's respective energy 

control procedure. 

The host employer often will have greater familiarity with the energy control procedures 

used at the host facility; however, at 29 CFR §1910.147(f)(2)(i), the standard requires the 

host and contract employers to inform each other about their respective energy control 

procedures. Such coordination is necessary to ensure that both sets of employees will be 

protected from the hazardous energy. The contractor must take reasonable steps 

consistent with its authority to protect its employees if the contractor knows, or has 

reason to know, that the host’s energy control procedures are deficient or otherwise 

insufficient to provide the requisite protection to its employees.

NOTE: The guidance provided in OSHA Instruction, CPL 02-00-124, Multi-Employer 

Citation Policy (December 10, 1999), must be used to determine host 

employer and contractor compliance with the LOTO standard. In all cases, the 

decision to issue §1910.147 citations to the host or contractor employer should 

be based on all of the relevant facts and the established policy for exposing, 

creating, correcting, and controlling employers. 

In IBP, Inc. v. Herman, 144 F.3d 861 (D.C. 1998), the Court of Appeals for 

the District of Columbia Circuit ruled that a host employer was not liable for 

the lockout/tagout violations of an independent contractor because, apart from 

pointing out the violations to the contractor, the host's control over those 

violations was limited to the cancellation of the contract. Proposed multi-
 2-32

employer citations should be approved through the OSHA Regional Office 

and the Solicitor’s Office.

VI. Affirmative Defenses. An affirmative defense is any matter that, if established by the 

employer, will excuse the employer from a violation that has otherwise been established 

by the Secretary of Labor. OSHA must be prepared to respond whenever an employer is 

likely to raise an argument supporting such a defense, and CSHOs should include 

documentation information useful to refute possible affirmative defenses in their case file 

documentation. [See the Field Inspection Reference Manual (FIRM), CPL 02-00-103, 

Section III.C.8.] The following are some examples of LOTO-related affirmative defenses 

that may be encountered: 

A. Greater Hazard. During the course of an inspection, a CSHO discovers that the 

employer is using freeze plug technology (in accordance with good engineering 

practice and the manufacturer’s recommended guidelines) to isolate a section of 

pipeline containing a hazardous substance in order to perform a repair. [Freeze 

Plug (Stop) Technology, as described by ANSI Z244.1-2003, is a non-intrusive 

method for isolation of piping systems (containing water/chemicals with suitable 

freeze points) through line freezing methodology.] The freeze plug is not an 

energy isolating device, as defined in §1910.147(b), but the employer 

convincingly demonstrates that it is a greater hazard to shut down/start up the 

process in order to repair the pipe. Under the circumstances specific to the 

process, the Area Director agrees with the defense and no citation is issued. 

NOTE: As there is a modification to the pipe in this scenario that would permit 

the installation of an energy isolation device (EID) or devices, the 

employer would be required, pursuant to §§ 1910.147(c)(2)(iii) and 

1910.147(d)(3), to ensure that sufficient EIDs (e.g., valves), which are 

capable of accepting a lockout device, are physically located to isolate 

the pipeline from the hazardous substance. Thus, a freeze plug would 

not be necessary for future isolation purposes because the 

incorporation of an EID(s) would permit sufficient process isolation 

capability to allow for the safe isolation of hazardous energy. 

 

Refer to Section III of this chapter and the Field Inspection Reference Manual 

(FIRM) for policy guidance. 

B. Impossibility. There may be scenarios where an employer, based upon a 

feasibility issue, cannot isolate hazardous energy sources when servicing and 

maintenance is performed during normal production operations. The 

impossibility defense would apply if: 1) LOTO was functionally impossible or 

would prevent the performance of work, and 2) there are no alternative means of 

employee protection. However, the impossibility defense does not relieve an 

employer from its obligation to provide a safe workplace to the extent possible by 

taking alternative steps to prevent employee injury. 
 2-33

For example, assume that the only alternative to performing servicing and/or 

maintenance work safely would be the complete system shutdown and disabling 

of a process in accordance with the LOTO standard. The fact that a shut down 

would be time consuming, costly or inconvenient would usually not excuse the 

employer from meeting its obligation to ensure safe and healthful working 

conditions in accordance with the OSH Act. 

C. Unpreventable Employee Misconduct and Isolated Instance. During the 

inspection, a CSHO observes an employee changing the die in an injection 

molding machine after the employee has pressed the stop button without locking 

out the machine in accordance with the company's established and compliant 

energy control procedure. Upon further investigation, it was discovered that this 

unsafe action occurred just minutes prior to the CSHO observation, and the 

condition was unknown to the employer. 

Interviews reveal that other employees consistently follow the die set procedures 

by locking out the machine in accordance with the established procedure. The 

company had a safety program, which included regular supervision of machinespecific energy control procedures, effective training, and uniform safety rule 

enforcement. At the informal settlement conference, the employer alleges that 

this inappropriate behavior constituted unpreventable employee misconduct, and 

the Area Director withdraws the citation for the alleged §1910.147(d)(4)(i) 

violation because the: 

1. Employer did not know, or have a reason to know, of the violative condition; 

and 

2. Established work procedures/rules were designed to prevent the violation and 

adequately communicated to the employees and supervisors; and the 

3. Employer had instituted a safety and health management program to discover 

violations of work procedures/rules together with the uniform enforcement of 

those work procedures/rules when they were violated.
 3-1

Chapter 3 INSPECTION GUIDANCE 

The following guidance, relative to specific provisions of 29 CFR 1910.147, is provided to assist 

Compliance Safety and Health Officers (CSHOs) in conducting inspections where the standard 

may be applicable: 

I. Purpose of the Standard. The purpose of this standard is to reduce the number of 

fatalities and injuries resulting from the failure to use practices and procedures necessary 

for the control of hazardous energy. This standard requires employers to establish an 

energy control program and to utilize energy control procedures to shut down or disable 

machines, isolate hazardous energy, and affix appropriate lockout or tagout devices to 

energy isolating devices prior to beginning servicing or maintenance work. These 

actions, if properly designed and implemented, will prevent the unexpected energization, 

start-up, or release of stored energy and prevent injury to employees. 

The standard’s scope, application, and purpose paragraphs [29 CFR §1910.147(a)] 

address a fundamental presumption underlying the standard -- that machines and 

equipment will be shutdown and disabled in accordance with the applicable energy 

control procedure before employees begin servicing and maintenance activities. 

Although some have contended that the standard does not apply when an employee is 

aware of the continuing presence of hazardous energy, this assertion is completely at odds 

with the language, purpose, and spirit of the standard. Quite simply, the LOTO standard 

is violated when an employee is, or may be, exposed to hazardous energy that has not 

been isolated, even if the employee knows that the energy has not been controlled and 

continues to constitute a hazard. Just as an employer cannot rely on an employee’s 

recognition of the hazard to avoid an obligation to guard machinery during normal 

operations, an employer cannot rely on an employee’s recognition of hazardous energy to 

avoid an obligation to shut down/disable the machine and isolate hazardous energy when 

employees service or maintain machinery. In both cases, reliance solely on employee 

awareness or knowledge of the presence of hazardous energy provides inadequate 

protection. Under no circumstances is any part of an employee’s body ever permitted to 

be exposed within a hazardous area, such as the point-of-operation or in-going nip point 

area, during servicing and/or maintenance activities while the machine is running or 

energized. Employers cannot evade their obligation under the LOTO standard by 

permitting or requiring employees to perform servicing and maintenance work on 

machines or equipment that are running or energized. See Burkes Mechanical, Inc., 21 

BNA OSHC 2136, 2139 n.4 (Docket No. 04-0475, 2007) and General Motors Corp., 

CPCG Oklahoma City Plant (Docket Nos. 91-2834E and 91-2950). 

NOTE: For purposes of this standard, employees working in energized machines or 

equipment that meet each element of the minor servicing exception criteria 

(including the utilization of measures which provide effective alternative 

protection) contained in §1910.147(a)(2)(ii) are not considered to be exposed 

to a hazardous area. 
 3-2

II. Scope and Application of the Standard. 

A. Unexpected Energization, Unexpected Start-up, and Release of Stored Energy. 

The title of the standard is the Control of hazardous energy (lockout/tagout), and 

the LOTO standard covers both forms (potential and kinetic) of hazardous energy. 

The regulation applies to all types of energy (e.g., electrical, mechanical, 

hydraulic, chemical, etc.). By establishing a program and procedures to control 

each type of hazardous energy, the standard protects employees from unexpected 

energization, start-up, or release of stored energy (potential energy) hazards. 

 

NOTE: Section 1910.147(a)(1)(i) addresses the potential energy hazards 

associated with unexpected energization or start up of machines or 

equipment, or the release of stored energy. The LOTO standard also 

applies when servicing and maintenance activities take place during 

normal production operations, if either of the circumstances in §§ 

1910.147(a)(2)(ii)(A) or (B) apply, and if the minor servicing 

exception is inapplicable. The predominant form of energy associated 

with normal production operation of a machine or piece of equipment 

is sometimes referred to as kinetic energy. 

The purpose of the Control of hazardous energy (lockout/tagout) standard, 

according to §1910.147(a)(3), is to: 

. . . require employers to establish a program and utilize procedures for 

affixing appropriate lockout or tagout devices to energy isolating devices 

and to otherwise disable machines or pieces of equipment to prevent 

unexpected energization, start-up or release of stored energy in order to 

prevent injury to employees. 

The standard protects employees by requiring the de-energization of machines or 

equipment and locking or tagging them out before the servicing or maintenance 

work is performed. Pursuant to the standard, the hazardous energy sources are 

effectively controlled through an energy control (LOTO) program, which includes 

the effective disabling and isolation of machines or equipment to prevent the 

release of hazardous energy during servicing and/or maintenance activities. 

The LOTO provisions give each authorized employee personal control over the 

hazardous energy sources to which they otherwise would be exposed. Servicing 

and maintenance can begin only after each authorized employee has placed her 

own LOTO device on the energy isolation device(s) or equivalent energy control 

mechanism. It is only when each authorized employee removes her personal 

LOTO device that the machine can be re-energized and started-up. It is the 

control that each employee maintains over the hazardous energy through her 

personal LOTO device that prevents the unexpected energization or start-up of the 

machine on which she is working – i.e., the phrase unexpected energization
 3-3

reflects the perspective of authorized employees who control hazardous energy 

exposure through personal LOTO devices, and any re-energization or start-up is 

considered to be unexpected unless each authorized employee has authorized such 

re-energization and start-up by removing her personal LOTO device from the 

energy isolation device or equivalent energy control mechanism. Thus, the term 

unexpected refers to any energization or start-up that is not sanctioned (through 

the removal of personal LOTO devices) by each authorized employee engaged in 

the servicing/maintenance activity. In promulgating the standard, OSHA did not 

intend to permit warning devices, which are designed to give employees notice of 

re-energization or start-up and intended to provide time to escape machine danger 

zones, to be used in lieu of energy isolation and personal LOTO devices. 

NOTE: For a more detailed discussion of the regulatory provisions evidencing 

the Agency’s intent that LOTO devices would be the means to protect 

employees from unexpected energization see Chapter 4 of this manual. 

Indeed, the exclusive use of warning devices subverts the intent of the standard by 

removing control over the hazardous energy from individual authorized 

employees and by placing the burden on exposed employees to become cognizant 

of and to recognize the significance of warnings, so that they can attempt to 

escape danger zones before they are injured. OSHA considered this approach to 

be impractical and dangerous if applied to workplaces throughout the nation. 

Thus, in promulgating the LOTO standard, the agency sought to prevent 

unexpected energization by establishing a requirement that employers follow 

energy control procedures that prohibit re-energization and start-up of machinery 

before each authorized employee has removed his personal LOTO devices. 

In promulgating the standard, it was OSHA's intent to protect employees 

effectively from all forms of hazardous energy by isolating machines from their 

respective energy sources during servicing and/or maintenance and providing 

individual authorized employees with control over energy isolation devices, and 

this intent is expressed in the Scope, application, and purpose paragraph, 

§1910.147(a), as well as throughout the preamble to the Final Rule. However, the 

Occupational Safety and Health Review Commission (OSHRC) and United States 

Court of Appeals for the Sixth Circuit have held that the standard did not apply in 

a situation where warning devices allowed adequate time for employees to move 

out of the danger zone and avoid employee injury. See General Motors Corp., 

Delco Chassis Div., 17 BNA OSHC 1217 (Nos. 91-2973, 91-3116, 91-3117, 

1995), aff'd., 89 F.3d 313 (6th Cir. 1996). 

GMC Summary: The OSHRC found that to service or maintain the three cited 

machines, an employee had to pass through electronically interlocked gates that 

immediately deactivated the machines when opened. The Commission further 

found that once deactivated, an eight to twelve step process had to be followed to 

restart each of the machines and that, either by audible or visual signals or the 

presence of company employees in the immediate work area, this multi-step 

process would have alerted employees servicing the machines that they were 
 3-4

about to start-up. Given the advance notice provided by the start-up warning 

sequences, the OSHRC reasoned that the standard did not apply because the 

energization would not be unexpected. The Commission held that the Secretary 

must establish that a cited machine or piece of equipment presents the hazard of 

unexpected energization or start-up. The United States Court of Appeals for the 

Sixth Circuit affirmed the Commission’s holding. 

Inspection strategy: While OSHA believes that the GMC decisions fundamentally 

misconstrue the LOTO standard, and the Agency may challenge this precedent in 

a future proceeding, the following policy and guidance is provided to assist 

Compliance Safety and Health Officers (CSHOs) in their inspection activity in 

light of the existing precedent. 

The GMC Delco decisions addressed the relatively uncommon situation in which 

a multi-step start-up procedure, time delays, and audible warnings were designed 

to enable employees to avoid injury even when the machine was started during the 

middle of a servicing procedure. In most situations where the LOTO standard 

applies, enforcement will not be affected by the GMC Delco decisions because the 

start-up mechanisms will not be designed and implemented to permit all 

employees to escape injury in all situations in which a machine or piece of 

equipment is re-energized or started while employees are performing servicing 

and/or maintenance activities. That was the case in Secretary v. General Motors 

Corp. CPCG Oklahoma City, OSHRC 91-2834E and 91-295 (OSHRC 2007), 

where the Commission held that the standard applied where equipment had been 

deactivated, but not locked out, during servicing. The Commission explained that 

the switches to operate the equipment were generally accessible, and GMC did not 

show that, once the switches were flipped, activation would not be immediate, or 

would follow some adequate warning. 

In addition, the GMC Delco decisions do not apply when an employer fails to turn 

the equipment off in the first place, and then claims that activation could not be 

unexpected because the employees knew the equipment was still operating. For 

example, in Secretary v. Burkes Mechanical, 21 BNA OSHC 2136, 2139 n.4 

(Docket No. 04-0475, 2007), the Commission did not accept an employer's 

contention that the standard did not apply because the employees knew that the 

conveyor they were servicing was running. It explained that the standard 

specifically applies to servicing during normal production operations, and 

allowing the equipment to operate during servicing presented exactly the type of 

hazard the standard is intended to address. See Section II.B of this Chapter. 

If an employer claims that the GMC Delco decision is applicable to its operation, 

or if the CSHO is aware that the employer is relying on warning or protective 

devices in lieu of lockout and tagout procedures, the case-specific facts must be 

thoroughly evaluated and documented to determine the adequacy and reliability of 

the particular safety feature(s). Areas of inquiry shall include both: 1) 

characteristics of the equipment, such as how it is intended to operate or whether 
 3-5

safety devices could be overcome by equipment failure or environmental factors; 

and, 2) human factors, such as inadequate employee training or particular 

characteristics of an individual employee that would reduce the effectiveness of 

safety devices. The following factors should be used to assess whether particular 

warning device(s) are adequate and reliable enough to allow all employees to 

escape all types of hazardous energy in all circumstances that may occur: 

1. The particular configuration and operation of the equipment. 

2. The nature of the servicing operations which put employees at risk, i.e., the 

particular procedures that the employees are using, the time during which 

servicing operations are performed, and the place where the servicing 

operations performed -- in, on, or around the machine or equipment. 

3. The ability of the servicing employees to move quickly out of the way of 

hazardous machine movement if other employees prematurely started the 

equipment – i.e., consider the amount of time between the warning signal and 

the machine's start-up in relation to the amount of time needed by all 

employees to escape or move to safety as well as the possibility of an 

employee slipping or getting caught when trying to exit the hazardous area. 

4. The ease of operating the machine's safety devices and whether the safety 

features easily could be circumvented by employees. 

5. The reliability of the safety features including whether mechanical failure can 

defeat their function. 

6. The likelihood that tools or equipment left behind (in a rapid escape scenario) 

could fly out and strike an employee or other wise cause injury. 

7. The adequacy of the instructions that are provided to employees regarding the 

safety features. Employees also should be questioned as to their knowledge 

and understanding of these instructions. 

8. The enforcement and supervisory oversight of the energy control procedures 

and work practices. For example, are supervisors, managers, and employees 

held accountable for their safety performance? 

9. Facts peculiar to individuals, which might have an effect on the adequacy or 

reliability of the safety features. For example, an employee's ability to hear 

and recognize an audible warning signal in a work environment will depend 

on factors such as the background noise levels, the strength and pitch of the 

warning signal, the employee’s position relative to the source of the warning 

signal and other noise sources in the area, and the particular employee’s 

hearing acuity. 

10. The signaling systems must be effective in warning employees who are 

exposed to hazardous energy during maintenance and servicing operations. If 
 3-6

the employer relies on visual signals, attention will have to be paid to the 

direction the employee is facing, any obstructions between the employee and 

the persons or moving parts that the employee must be able to see, any reason 

why the employee’s attention might be directed elsewhere, the lighting 

conditions in the area, and possible deficiencies in the employee’s eyesight. 

For example, a nearsighted employee may be able to service nearby parts 

without being able to clearly see movements that may be some distance away. 

Visual signals that are sufficient for an employee with 20-20 vision may be 

inadequate for other employees. 

11. Near miss data and injury experience due to inadequacies in or deviations 

from the energy control procedures and practices. 

These factors, together with any other pertinent information, must be carefully 

evaluated and documented. In situations where warning or protective devices are 

in use and an analysis indicates that they are not effective in all situations, a 

citation should be issued after consultation with the OSHA Regional Office. In 

addition, because the standard requires the use of personal LOTO devices to 

protect employees from hazardous energy, and because the failure to use personal 

LOTO devices deprives authorized employees of their control over the hazardous 

energy, an Area Director may issue a citation for a violation of the standard, even 

if it appears that other warning or protective devices provide a significant level of 

protection against hazardous energy. However, in such cases, the citation must be 

authorized by the OSHA Regional Office and the Solicitor’s Office before it is 

issued. 

B. Normal Production Operations. 

Normal production operations occur during the utilization of a machine or piece 

of equipment to perform its intended production functions. The Subpart O, 

Machinery and Machine Guarding, requirements of 29 CFR §1910 apply to these 

operations. Thus, Subpart O complements the LOTO standard requirements. 

Activities that are necessary to prepare or maintain a machine or piece of 

equipment are not considered utilization and are considered servicing and/or 

maintenance activities. Some of these workplace activities may include 

constructing, installing, setting up, modifying, maintaining, lubricating, cleaning, 

un-jamming, making minor adjustments, and tool changes. 

Safeguarding of servicing and maintenance employees during normal production 

operations can be ensured either by: 

1. Effective machine/equipment safeguarding in compliance with Subpart O; or 

2. Compliance with 29 CFR §1910.147 in situations where normal production 

operations safeguards are rendered ineffective or do not protect the employees 
 3-7

from exposure to hazardous energy during servicing and maintenance 

operations. 

If a servicing or maintenance activity takes place as part of the normal production 

operation, the employee performing the servicing or maintenance may be 

subjected to hazards not normally associated with the traditional production 

process. Although the machine guarding provisions in Subpart O of 29 CFR 

§1910 cover normal production operations, employees engaged in servicing or 

maintenance during normal production operations must follow LOTO program 

requirements if they: 

1. Remove or bypass machine guards or other safety devices; 

2. Place any part of their bodies in or near a machine’s point of operation; or 

3. Place any part of their bodies in a danger zone associated with machine 

operations. See §1910.147(a)(2)(ii)(A) and (B). 

If the servicing or maintenance is performed during normal production operations 

and none of the conditions stated above exist, a violation of 29 CFR §1910.147 

does not exist. [Refer to the guidance in Section IV of this chapter on the minor 

servicing exception to §1910.147(a)(2)(ii).] 

NOTE: The applicability of the standard (§1910.147 versus Subpart O 

standards) directly relates to the type of work being performed 

(servicing and/or maintenance versus normal production operations) 

and not to the means of abatement (LOTO versus safeguarding). For 

example, cleaning the rollers of an unguarded press, where the 

employee is exposed to in-going nip point hazards, is a LOTO standard 

violation and not a machine guarding violation because cleaning is a 

servicing activity. See §1910.147(a)(2)(ii)(B). However, compliance 

officers can not cite an employer for LOTO violations when effective 

machine guarding techniques are used to eliminate the hazardous 

(mechanical) energy employee exposures. 

The Compliance Assistance Flowcharts, Figures 3-1 and 3-2, may be 

consulted for analysis purposes. Also, Section IV of this chapter 

should be consulted for a description of the minor servicing exception. 

Furthermore, there are some tasks, such as machine or equipment inspection, 

which may either constitute “servicing and/or maintenance” or “normal 

production operation” activities depending upon the specific circumstances of the 

work tasks. The purpose or function of the activity determines which standard 

applies. If the inspection activity is conducted to determine product quality or it is 

functionally related to the product, then it is a normal production operation. 

Conversely, if the inspection is performed to troubleshoot a mechanical problem 

or determine the adequacy of an equipment or machine repair, then the inspection 
 3-8

is a “servicing and/or maintenance” activity that is addressed by the LOTO 

standard. 

NOTE: Due to changing job responsibilities in the American workplace today, 

some production employees’ (e.g., machine operators, process 

operators) duties are expanding so that their work tasks may include 

servicing and/or maintenance activities that are subject to the 

requirements of the LOTO standard. 

C. Lockout/Tagout’s Relationship to Other OSHA Standards. 

1. Supplemental Aspect. The Control of hazardous energy (lockout/tagout)

standard makes clear in §1910.147(a)(3)(ii) that it is not intended to replace 

other existing standard provisions for LOTO, but to supplement and support

these provisions by requiring that employers establish an energy control 

procedure and train employees in the energy control program as detailed in 

§1910.147. Various OSHA standards impose lockout-related requirements, 

but do not address LOTO issues or methodology in any detail. For example, 

some OSHA standards require equipment to have the capability of being 

locked out, while other OSHA standards mandate the specific use of lockout, 

tagout or other energy control devices for certain machines, equipment or 

industries. 

NOTE: This means that, when another Part 1910 standard requires the use 

of lockout or tagout, that standard should be cited when a violation 

is found. The §1910.147 procedural and training requirements also 

apply, however, and should be cited when appropriate. If the other 

Part 1910 requirement requires specific control measures, such as 

the use of lockout only, then the 1910.147 lockout procedures and 

lockout-related training would need to be implemented in 

conjunction with the lockout measures contained in the other Part 

1910 standard. 

Any provision of the LOTO standard may be cited, as appropriate, 

when the vertical standard specifies only that the machine or 

equipment must have the capability of being locked out because 

the provision does not, in fact, require the use of LOTO. 

The following list indicates a number of OSHA standards that currently have 

LOTO related requirements. The list does not necessarily include all 29 CFR 

§1910 standards that have LOTO provisions: 

a) 29 CFR 1910.119(f)(4), Process Safety Management of Highly Hazardous 

Chemicals; 
 3-9

b) 29 CFR 1910.146(d)(3) and 1910.146(c)(7), Permit Required Confined 

Spaces; 

c) 29 CFR 1910.178(q)(4), Powered Industrial Trucks; 

d) 29 CFR 1910.179(g)(5)(i), (ii), & (iii), 1910.179(l)(2)(i)(b), (c) & (d), 

Overhead and Gantry Cranes; 

e) 29 CFR 1910.181(f)(2)(i)(c) & (d), Derricks; 

f) 29 CFR 1910.213(a)(10), 1910.213(b)(5), Woodworking Machinery; 

g) 29 CFR 1910.217(b)(8)(i), 1910.217(b)(9)(iv), Mechanical Power Presses; 

h) 29 CFR 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), 1910.218(h)(5), 1910.218(i)(1), 1910.218(i)(2), 

1910.218(j)(1), Forging Machines; 

i) 29 CFR 1910.244(a)(2)(iii), Other Portable Tools and Equipment, Jacks; 

j) 29 CFR 1910.253(b)(5)(iii)(D), Oxygen-Fuel Gas Welding and Cutting; 

k) 29 CFR 1910.254(c)(3)(i), 1910.254(d)(5), Arc Welding and Cutting; 

l) 29 CFR 1910.255(a)(1), Resistance Welding; 

m) 29 CFR 1910.261(b)(1), 1910.261 (f)(6)(i); 1910.261(g)(15)(i), 

1910.261(g)(19)(iii), 1910.261(j)(4)(ii); 1910.261(j)(5)(iii); 

1910.261(k)(2)(i), Pulp, Paper, and Paperboard Mills; 

n) 29 CFR 1910.262(c)(1), 1910.262(n)(2), 1910.262(p)(1), 1910.262(q)(2), 

Textiles; 

o) 29 CFR 1910.263(l)(3)(iii)(b), 1910.263(l)(8)(iii), Bakery Equipment; 

p) 29 CFR 1910.265(c)(13), 1910.265(c)(26)(v), Sawmills; 

q) 29 CFR 1910.266(h)(4), Logging; 

r) 29 CFR 1910.268(m)(7), Telecommunications; 

s) 29 CFR 1910.272(e)(1)(ii), 1910.272(g)(1)(ii), 1910.272(m)(4), Grain 
 3-10

Handling; and 

t) 29 CFR 1910.305(j)(4)(ii)(A), 1910.305(j)(4)(ii)(C)(1), Wiring Methods, 

Components, and Equipment for General Use. 

2. Relationship between the Control of hazardous energy (LOTO) standard and 

the Permit-required confined spaces (PRCS), 29 CFR §1910.146, standard. 

The PRCS and the LOTO standards are generic and interrelated standards, and 

both standards may, depending upon the circumstances, apply to the isolation 

of hazardous energy for a PRCS. The application of the LOTO standard, with 

respect to PRCS, is governed by §1910.147(a)(3)(ii), which provides that, 

when other standards require LOTO, the procedural and training provisions of 

the LOTO standard shall be used and supplemented to effectively control 

hazardous energy. Therefore, for any particular PRCS, the question will be 

whether the 1910.146 standard requires LOTO to isolate hazardous energy. 

The answer to this question depends on the type(s) of hazardous energy that 

must be isolated, whether LOTO provides isolation (offering complete 

employee protection), and whether the §1910.146 requires the use of LOTO. 

Pursuant to the §1910.146 standard (including its final rule preamble), electromechanical types of hazards, associated with a PRCS, must be isolated in 

accordance with the LOTO standard (or guarded in accordance with Machine 

guarding, Subpart O, requirements). Failure to follow the procedural and 

training requirements of the LOTO standard should be cited as §1910.147 

violations related to the isolation of electro-mechanical hazards. 

The PRCS standard does not, however, allow LOTO for flowable material 

isolation. This is because compliance with §1910.147 does not, in all cases, 

adequately isolate hazards created by materials such as steam, flammable 

gases, flammable and combustible liquids. In a permit-required confined 

space, hazards associated with flowable materials will be considered isolated 

only by the use of the following techniques: blanking or blinding; misaligning 

or removing sections of lines, pipes or duct; and use of a double block and 

bleed system. A double block and bleed isolation system, for example, 

usually utilizes the closure of two valves, the opening of a bleeder valve, and 

the application of LOTO devices (offering complete employee protection); 

whereas an employer can comply with §§ 1910.147(d)(3) and 1910.147(d)(4) 

of the LOTO standard by simply closing and LOTO of a single valve (which 

could create atmospheric hazards due to the leakage of a single valve). 

3. Relationship between the Control of hazardous energy (LOTO) standard and 

29 CFR §1910, Subpart S. Employee exposure to electrical hazards (e.g., 

shock, arc flash burn, thermal burn, blast) from work on, near, or with 

conductors or equipment in electric utilization installations, which are covered 

by Subpart S, Electrical, is excluded from coverage by the LOTO standard. 

Subpart S provisions have their own lockout and tagging requirements for 
 3-11

controlling hazardous electrical energy. However, an employer may utilize 

hazardous energy control program paragraphs 1910.147(c) through (f) to 

comply with the electrical lockout and tagging requirements set forth in 

1910.333(b)(2), provided that the energy control procedures: 

a) Address the electrical safety hazards of Subpart S; 

b) Incorporate the application of locks and tags pursuant to §1910.333 

(b)(2)(iii)(D); and 

c) Incorporate the specific electrical verification provision requiring a 

qualified person to use (after checking the instrument for proper operation) 

a test instrument to verify circuit and equipment de-energization -- 

pursuant to §1910.333(b)(2)(iv)(B). 

Employee exposure to non-electrical hazards from electrically powered 

machines or equipment (electric utilization systems) is covered by §1910.147. 

For example, §1910.147 applies to a rotary valve un-jamming task, even if the 

valve’s energy source is electrical, since employees are exposed to mechanical 

hazards. 

4. Relationship between the Control of hazardous energy (LOTO) standard and 

the Telecommunications, 29 CFR §1910.268, standard. The 1910.268 

standard contains provisions setting forth requirements specific to work 

performed in the telecommunications industry. 

NOTE: Radio and television broadcasting systems and transmitting towers 

for cellular telephones, personal communication services, pagers, 

cordless telephones, radio communications for police and fire 

departments, amateur radio, microwave point-to-point radio links 

and satellite communications are some of the applications of radio 

frequency electro-magnetic fields used for telecommunications. 

Radio frequency energy may cause damage to a biological system, 

and it is considered hazardous energy when it has the capability to 

cause injury to employees performing telecommunication system 

servicing and/or maintenance work. For additional information, 

refer to the FCC, Office of Engineering and Technology’s web site 

[e.g., OET Bulletin #56] regarding the hazards of radio frequency 

electromagnetic fields at http://www.fcc.gov/oet/rfsafety. 

 Section 1910.268 addresses three situations requiring some form of hazardous 

energy control: 

1. Radio transmitting station (3-30 MHz) antenna work – pursuant to 

§1910.268(m)(7); 

2. Microwave transmission (1 GHz to 300 GHz, inclusively) work – pursuant 
 3-12

to §§ 1910.268(p) and (s)(29); and 

3. Other types of telecommunications (at all other telecommunication 

frequencies) work. 

The radio transmitting station provisions, addressed in §§1910.268(m)(7)(i) 

through (vi), require specific radio-frequency energy control measures for 

antenna work. This section contains hazardous energy control steps for radiofrequency energy (3-30 MHz) associated with broadcasting equipment and 

specific communication requirements that must take place between the riggerin-charge and the transmitting technician. This prescribed control procedure 

also includes requirements for transmitter shutdown, the use of danger tags, 

antenna grounding, testing, and other safe work practices, including steps to 

re-energize the system and return the job back to the transmitter technician in 

charge of the work. 

In addition, the standard's general training provision, §1910.268(c), also 

applies to hazardous energy control involving the radio antenna work 

described above. These training provisions require employers to ensure that 

employees are trained (either on-the-job or classroom) in the various 

precautions and safe practices described in the telecommunications standard. 

In terms of the application of §1910.147 to radio station antenna energy 

control procedures and training requirements, the applicable provisions of § 

1910.268 are supplemented and supported by the procedural and training 

requirements of the LOTO standard to the extent that they are not regulated by 

the specific energy control provisions of the §1910.268. See 

§1910.147(a)(3)(ii). For example, the telecommunications standard’s training 

certification provisions contained in paragraph 1910.268(c) prevail over the 

LOTO standard’s training certification requirements contained in 

§1910.147(c)(7)(iv) as both standards address the same issue. 

 NOTE: Paragraph (c) of the telecommunications standard provides a 

training exception in cases where an employer can demonstrate that 

an employee has already been trained in the precautions and safe 

practices required by 1910.268 prior to his employment. For 

example, if an employer demonstrates through employment records 

that the employee met the required training, then a training 

certification is not required because the employer did not need to 

perform the training. 

With respect to microwave electro-magnetic energy communication systems 

operations, §§ 1910.268(p)(1) through (p)(3) allow for the control of 

hazardous energy without LOTO; therefore, LOTO is not required, and the 
 3-13

1910.147 standard does not apply. 

With respect to all other types of telecommunication work aside from the 

radio transmitting station (3-30 MHz) antenna work and the microwave 

transmission (1 GHz to 300 GHz, inclusively) work described above, 

§1910.147 would apply exclusively as the 1910.268 standard does not address 

hazardous energy control practices for these work activities. 

5. Relationship between the Control of hazardous energy (LOTO) standard and 

the Electric Power Generation, Transmission, and Distribution 29 CFR 

1910.269, standard. Installations that are under the exclusive control of 

electric utilities, and equivalent installations in industrial environments, are 

covered by the Electric power generation, transmission, and distribution 

standard and not by the LOTO standard. Installations in electric power 

generation facilities that are not an integral part of, or inextricably 

commingled with, power generation processes or equipment are covered, as 

appropriate, under §1910.147 and Subpart S standards. See §1910.269(d)(1). 

6. Relationship between the Control of hazardous energy (LOTO) and the Grain 

handling facilities, 29 CFR 1910.272, standards. The grain handling facilities 

standard contains provisions setting forth safety, fire, and explosion protection 

requirements specific to work performed in the grain handling facilities. The 

following industry-specific regulations apply to work conditions and 

hazardous energy control practices that are specific to grain handling 

operations: 

a. Training [§1910.272(e)(1)(ii)]; 

b. Specific energy control actions [§1910.272(g)(1)(ii)]; and 

c. Lock and tag procedure implementation [§1910.272(m)(4)]. 

The provisions of this grain handling standard apply in addition to any other 

applicable requirements of Part 1910. In terms of the application of 

§1910.147, these particular grain handling provisions are supplemented and 

supported by the procedural and training requirements of the LOTO standard 

to the extent that they are not regulated by the specific hazardous energy 

control provisions of the listed 1910.272 standards. See §§ 1910.147(a)(3)(ii) 

and 1910.272(a). 

For example, the more stringent requirement to implement procedures for tags 

and locks, contained in §1910.272(m)(4), prevails over the LOTO standard’s 

paragraph (c)(4)(i) requirement to utilize an energy control procedure when 

employees are engaged in activities covered by §1910.147. [The LOTO 

standard permits an employer to establish a lockout program or, conditionally, 

an equally protective tagout program.] However, the supplementary 

hazardous energy control procedure provisions, contained in §§ 1910.147 

(c)(4)(i) and (ii), to develop and document procedures with sufficient detail 
 3-14

and adequate guidance on how to safely utilize control measures still apply 

because these procedures are not addressed by the grain handling standard. 

7. General Industry Workplaces. The standard applies to all general industry 

workplaces in which servicing and/or maintenance activities take place 

because the risks associated with hazardous energy are so pervasive and arise 

during such a wide variety of activities. Accordingly, the standard’s coverage 

is expressed on a general industry-wide basis rather than on an industry-byindustry basis. The control of hazardous energy standard addresses machines 

and equipment that may expose employees to injury during servicing and/or 

maintenance activities. 

Some machines and equipment covered by the control of hazardous energy 

standard include: 

a) Amusement and recreational service machinery and equipment, including 

large rides and other amusement (e.g., bowling machines) equipment; 

b) Apparel manufacture machinery and equipment, including industrial 

sewing machines; 

c) Automotive repair, service, and garage machinery and equipment, 

including automobiles, trucks, material handling equipment, tire repair 

machines, hoisting equipment, automotive lifts; 

d) Chemical process systems and piping networks; 

e) Communications industry machines and equipment, including 

telecommunication towers; 

f) Elevators, escalators and passenger conveyors; 

g) Fire alarm and extinguishing systems and their components; 

h) Food store machinery and equipment, including packaging machinery, 

conveyors, meat cutting and bakery equipment; 

i) Gas and sanitary service machinery and equipment, including water, 

steam, irrigation, and sewage pipelines; 

j) Heating, ventilating and air conditioning systems; 

k) High intensity electromagnetic field machinery and equipment (regulated 

by 29 CFR §1910.97, Non-ionizing radiation); 

l) Ionizing radiation machinery and equipment (regulated by 29 CFR 

§1910.1096); 

m) Laundry and dry cleaning machinery and equipment; 

n) Manufactured home builder - manufacturing activities; 

o) Pipelines transporting hazardous substances; 

p) Railroad machinery and equipment, including railroad cars; 

q) Transportation machinery and equipment, including airplanes, helicopters, 

mobile passenger loading tunnels, and baggage handling equipment, 

including conveyors; and 

r) Trucking and warehousing, including freight elevators, trucks, material 

handling equipment, and cranes. 
 3-15

NOTE: Some of the listed machines and equipment may not be subject 

to the LOTO standard requirements if they are pre-empted [in 

accordance with Section 4(b)(1) of the Occupational Safety and 

Health Act] by other Federal regulations, such as regulations 

promulgated and enforced by the Department of 

Transportation, Office of Pipeline Safety and Federal Aviation 

Administration. For specific information on DOT regulations 

and related information, enforcement personnel may refer to 

http://www.ops.dot.gov and http://www.faa.gov web sites. 

8. Chemical Process and Piping Systems. The Control of hazardous energy

(lockout/tagout) standard regulates the servicing and/or maintenance of 

chemical process systems, and associated piping, even though the energy 

sources (e.g., chemical and thermal energy) and control methods used in 

process hazards management are somewhat different from those encountered 

with machinery and mechanical equipment. 

Typically, the procedural steps required for safe performance of process 

system and piping network maintenance or servicing are: 1) deactivation, 2) 

removal of contents, 3) isolation, 4) decontamination, 5) restraining, 6) 

verification, 7) control, and 8) communication. The primary difference, 

relative to typical machinery energy control practice, is the means used to 

isolate (e.g., blank flanges, slip blinds) the energy in the process and piping 

network system. 

NOTE: Bolted blank flanges, slide gates, or slip blinds are considered 

piping energy isolating devices and also are acceptable as lockout 

devices if they are used as part of a standard, documented 

procedure. If bolted flanges or slip blinds are used, the equipment 

must be shutdown in an orderly fashion so as not to create 

additional or increased hazards to employees. For example, 

without proper isolation and de-pressurization of the hazardous 

energy, employees opening pipelines to install blinds may be 

exposed to pressure-related and/or fire-safety hazards. 

 Additionally, these devices must meet the other requirements of the 

standard for lockout devices (e.g., they must be durable, 

standardized, substantial, and identifiable). 

The deactivation of a process system is equivalent to equipment shutdown. 

Similarly, removing the contents of the piping system and isolation of the 

energy source is equivalent to isolation and lockout or tagout of a machine or 

equipment, and the use of decontamination and restraining in piping systems 

is equivalent to the restraining or dissipating of stored energy in machines or 

equipment. Finally, verifying effective isolation is essential for both chemical 
 3-16

process and piping network systems and other machines or equipment. 

D. Standard Exemptions. The LOTO standard does not apply to: 

1. Construction, agriculture, and maritime employment; 

2. Installations under the exclusive control of electric utilities, and equivalent 

industrial installations, that generate, transmit, and distribute electric power, 

including related equipment for communication or metering. However, 

installations in electric power generation facilities that are not an integral part 

of, or inextricably commingled with, power generation processes or equipment 

are covered, as appropriate, under §1910.147 and Subpart S standards. See 

Section II.C.5 of this chapter; 

3. Exposure to electrical hazards from work on, near, or with conductors or 

equipment in electric utilization installations, which is covered by Subpart S 

of this part. See Section II.C.3 of this chapter; 

4. Oil and gas well drilling and servicing installations; 

NOTE: Oil and gas production facilities are not included in the oil and gas 

well drilling and servicing exception because drilling and servicing 

activities are distinct from production operations. Drilling and 

servicing covers activities related to the initial drilling of a well 

and later, maintenance work necessary to maintain or enhance 

production. Oil well drilling and servicing includes the following 

activities: 

a) Actual drilling and associated activities of the well; 

b) Well completion activities (i.e., activities and methods 

necessary to prepare a well for the production of oil and gas); 

c) Well servicing (i.e., the maintenance work performed on an oil 

or gas well to improve or maintain the production from a 

formation already producing. Usually it involves repairs to the 

pump, rods, gas-lift valves, tubing, packers and so forth); and 

d) Work-over activities (i.e., the performance of one or more of a 

variety of remedial operations on a producing oil well to try to 

increase production). Examples of work-over operations 

include deepening, plugging back, pulling and resetting liners, 

squeeze cementing and so on. 

 Production, on the other hand, is a phase of well operations that 

deals with bringing well fluids to the surface, separating them, and 

then storing, gauging and otherwise preparing the product for 

distribution. This production phase occurs after a well has been 

drilled, completed, and placed into operation, or after it has been 

returned to operation following work-over or servicing. A 
 3-17

completed well can include a Christmas tree (control valves, 

pressure gauges and choke assemblies to control the flow of oil and 

gas), which is attached at the top of the well and it is the point 

where the potential coverage of LOTO begins. 

5. Cord- and plug-connected electric equipment (e.g., industrial sewing 

machines) when unplugging the equipment from the energy source completely 

controls the hazardous energy and when the plug is under the exclusive 

control of the employee performing the servicing and/or maintenance. This 

exclusion applies to portable electric tools, as well as to cord- and plugconnected equipment which is intended for use at stationary or fixed locations; 

and 

NOTE: The D.C. Court of Appeals upheld the Secretary’s interpretation of 

the “cord-and-plug” exemption to OSHA’s lockout/tagout 

standard. Because employees serviced cord-and-plug connected 

equipment that was not unplugged during the servicing, “the 

Commission did not err in finding the exemption inapplicable.” 

The Secretary interprets the exemption as applying to work on 

cord-and-plug equipment only if the equipment is unplugged and 

the plug is in the exclusive control of the servicing employee. See 

Tops Markets, Inc., (OSHRC Docket No. 94-2527, 1997) for 

background information. 

6. Hot tap operations on pressurized pipelines that distribute substances like gas, 

steam, water, or petroleum products, if the employer shows that: 1) continuity 

of service is essential; 2) shutdown of the system is impractical; and 3) 

documented procedures are followed and special equipment is used that 

provides proven, effective employee protection. 

E. Compliance Assistance Flowcharts. The Figure 3-1 flowchart illustrates the 

compliance relationship among the following standards that protect employees 

from hazardous energy: 1) the Control of Hazardous Energy (Lockout/Tagout)

standard; 2) Subpart O, Machinery and Machine Guarding, standards; and 3) 

Subpart S, Electrical – Safety-Related Work Practices (ESRWPs), standards. 

This flow diagram addresses machine or equipment energy sources where the 

energy may injure employees (hazardous energy) and shows whether the electrical 

safety-related work practices (e.g., §§ 1910.332, 1910.333, 1910.335), machine 

guarding (e.g., §§ 1910.212, 1910.213, 1910.217, 1910.219), and/or LOTO

(1910.147) standards apply. 

NOTE: OSHA has established, in its Subpart S standards, a threshold value of 

50 volts that requires electric equipment or circuits to be de-energized 

when employees perform work near or on exposed energized circuit 

parts. However, other hazards may exist with low voltage electric 

energy. This 50-volt electric shock threshold does not pertain to the 

application of §1910.147, and the LOTO standard would apply to 

electrical sources (not covered by Subpart S or §1910.269) at any 
 3-18

voltage whenever there is sufficient energy present to injure 

employees. 

 For example, low voltage industrial batteries have exploded when they 

were not properly isolated from systems during maintenance activities. 

Low voltage equipment that is not covered by Subpart S (such as an 

automotive wiring system) has caused thermal hazards and burns due 

to heat generation from electrical resistance, while other low voltage 

equipment has provided enough energy to ignite vapor clouds during 

maintenance work on equipment containing flammable substances.

To further aid in complying with the LOTO standard, the Implementation of 

Lockout/Tagout functional flow diagram, Figure 3-2, may be consulted. 

NOTE: In situations where hazardous energy is not adequately controlled, an 

employer must identify the control problem and correct the hazard 

prior to the performance of servicing and maintenance work on the 

machine or equipment. As such, an employer needs to systematically 

analyze whether there were any deviations from or inadequacies in 

their energy control program and take appropriate action to resolve the 

problem. 

These compliance assistance tools do not constitute exclusive or definitive means 

of complying with the standard in any particular situation and are presented solely 

as an aid. As explained in this scope and application section, these flowcharts do 

not address energy control provisions in other OSHA standards that 

complement/supplement the requirements in §1910.147. Also, the LOTO 

implementation diagram (Figure 3-2) does not include the additional requirements 

in paragraph 1910.147(f). 
 3-19

Figure 3-1: LOTO vs. Machine Guarding vs. Electrical Safety-Related Work Practices1 

1 This flow diagram does not address energy sources covered by §1910.269 requirements and it does not 

contain the exemptions, including the minor servicing exception, to the LOTO standard [See 

§1910.147(a)].

To Figure

3-2a

Is hazardous

energy exposure

present?

Working

on/near

exposed live

electrical parts

Machine/equip.

servicing or

maintenance

work?

Stop

Apply Electrical

Safety-Related

Work Practices

(Subpart S)

Apply

Machine Guarding

(Subpart O)

Apply

Lockout/Tagout 1

(1910.147)

No

No

Yes

Start

Yes

Yes

No

Is other

hazardous energy

present?

No

Yes

To Figure

3-2a

Is hazardous

energy exposure

present?

Working

on/near

exposed live

electrical parts?

Machine/equip.

servicing or

maintenance

work?

Stop

Apply Electrical

Safety-Related

Work Practices

(Subpart S)

Apply

Machine Guarding

(Subpart O)

Apply

Lockout/Tagout 1

(1910.147)

No

No

Yes

Start

Yes

Yes

No

Is other

hazardous energy

present?

No

Yes
 3-20

Figure 3-2a: Implementation of Lockout/Tagout (Part 1) 

Conduct machine/

equipment

hazard analysis.

Develop documented

energy control procedure(s) (c)(4)

Provide training to

affected employees

(c)(7)(i)(B)

Provide detailed training to

authorized employees

(c)(7)(i)(A)

Provide training to

all other employees

(c)(7)(i)(C)

Assign maintenance/service task to authorized employee(s)

And

Consult applicable energy control procedure(s)

Shutdown preparation

(d)(1)

Shut down machines or equipment

(d)(2)

Identify all energy isolation devices

(EIDs) per established procedure

Obtain lockout/tagout

device(s)

Can EID be

locked out?

(c)(2)

Use a tagout

program

Use lockout or a

tagout program with

“full employee

protection” (d)(3)

Lockout/Tagout

EID(s) (d)(4)

Isolate

(d)(3)

From

Figures 3-1 

and 3-2b

Yes No

To

Figure 3-2b

Notify affected

employees (c)(9)

Tagout EID(s)

(d)(4)

Conduct machine/

equipment

hazard analysis.

Develop documented

energy control procedure(s) (c)(4)

Provide training to

affected employees

(c)(7)(i)(B)

Provide detailed training to

authorized employees

(c)(7)(i)(A)

Provide training to

all other employees

(c)(7)(i)(C)

Assign maintenance/service task to authorized employee(s)

And

Consult applicable energy control procedure(s)

Shutdown preparation

(d)(1)

Shut down machines or equipment

(d)(2)

Identify all energy isolation devices

(EIDs) per established procedure

Obtain lockout/tagout

device(s)

Can EID be

locked out?

(c)(2)

Use a tagout

program

Use lockout or a

tagout program with

“full employee

protection” (d)(3)

Lockout/Tagout

EID(s) (d)(4)

Isolate

(d)(3)

From

Figures 3-1 

and 3-2b

Yes No

To

Figure 3-2b

Notify affected

employees (c)(9)

Tagout EID(s)

(d)(4)
 3-21

Figure 3-2b: Implementation of Lockout/Tagout (Part 2) 

This flow diagram does not constitute the exclusive or definitive means of complying with the standard in any particular 

situation. It is presented solely as an aid. Also, it does not include paragraph (f) Additional requirements. 

Perform task

Retrieve tools, etc., ensure

system components intact

(e)(1)

Verify personnel

clear and

accounted for (e)(2)

Remove

Lockout/Tagout

devices

Notify affected

Employees (c)(9) and (e)(2)

Return equipment to

operation per procedures

From

Figure 3-2a

Hazardous

energy

controlled?

Yes

To

Figure 3-2a

No

Dissipate stored energy

to safe level(s) (d)(5)

Continue

verification

if energy

reaccummulation

possible

Verify isolation

(d)(6)

Perform task

Retrieve tools, etc., ensure

system components intact

(e)(1)

Verify personnel

clear and

accounted for (e)(2)

Remove

Lockout/Tagout

devices

Notify affected

Employees (c)(9) and (e)(2)

Return equipment to

operation per procedures

From

Figure 3-2a

Hazardous

energy

controlled?

Yes

To

Figure 3-2a

No

Dissipate stored energy

to safe level(s) (d)(5)

Continue

verification

if energy

reaccummulation

possible

Verify isolation

(d)(6)
 3-22

III. Vehicle Hazardous Energy Control. 

A. Background. Serious injuries and death have occurred and continue to occur from 

inadequate hazardous energy control during vehicle servicing and maintenance 

activities. In 1991, the U.S. Court of Appeals for the District of Columbia 

remanded the LOTO standard to OSHA for further consideration of the ways in 

which the final rule applies to all general industry workplaces. OSHA, in the 

March 30, 1993 Federal Register (Vol. 58, No. 59), reaffirmed and further 

explained the reasons for applying the standard to vehicle servicing and 

maintenance. The scope and application sections of the preamble to the 

hazardous energy control standard provide that the LOTO standard applies to all 

“general industry workplaces.” The standard's coverage includes vehicles, such 

as, but not limited to, automobiles, trucks, tractors, refrigeration transport 

vehicles, and material handling equipment. 

B. Hazardous Energy. Generally speaking, for purposes of vehicle servicing and 

maintenance, hazardous energy refers to: mechanical motion; potential energy due 

to pressure, gravity, or springs; battery-generated electrical energy; thermal 

energy, including chemical energy; and other forms of energy, which can cause 

injury to employees working in, on, or around machines or equipment. Any 

vehicle [e.g., internal combustion engines such as gasoline, natural gas and diesel 

powered vehicles; electric-powered vehicles; hybrid (gasoline/electric) vehicles] 

may contain the following types of hazardous energy, such as, but not limited to: 

1. Chemical energy due to contact with battery acid, coolant, lubricants; 

2. Electric battery shock, arc, and burn hazards; 

3. Explosion hazards associated with air bags; 

4. Fire and explosion hazards associated with the fuel and fluid systems; 

5. Gravitational energy (mechanical) hazards caused by elevated vehicles (e.g., 

unsafe use of automotive lift equipment) or vehicle components (e.g., 

unsupported elevated dump truck beds; unsupported elevated forklift carriage 

assembly); 

6. Hot or cryogenic fluid, and surface (thermal) hazards; 

7. Hydraulic hazards associated with fluid pressure and fluid loss (e.g., causing a 

carrier bed to drop); 

8. Mechanical hazards associated with disc brake spring and tire components; 

9. Mechanical motions due to moving power transmission components; 

10. Premise wiring electric hazards associated with battery recharging (which are 

addressed by the Subpart S - Electrical standards); and 

11. Mechanical hazards associated with unexpected start-up or unexpected 
 3-23

energization of vehicles or vehicle components. 

C. Energy Control Program. The 29 CFR 1910.147 standard requires an employer to 

develop an energy control program that is tailored to the workplace and will 

protect employees performing servicing and maintenance tasks from the release of 

hazardous energy. The performance-oriented language allows employers 

flexibility to design and implement the required energy control procedures, 

employee training requirements, and inspection requirements to fit the individual 

conditions present in their workplaces. The selection of the specific method of 

control must reflect a thorough evaluation of the extent of exposure to the hazard; 

the risk of injury associated with the particular machine/equipment; and the 

feasibility of applying a particular method of control. 

Due to the nature and unique aspects of vehicle maintenance and servicing 

activities, the control of hazardous energy final rule's preamble recognizes feasible 

measures to prevent an engine from being started. OSHA references situations, 

involving vehicles, such as automobiles, buses, and over-the-road trucks, where 

the removal of the ignition key ensures that the engine can not be started. 

However, this simple control step of removing the ignition key may not, in all 

cases, adequately control other types of vehicle hazardous energy, such as is the 

case with the positioning of the vehicle or its components (e.g., buckets, blades, 

vehicle body parts). These and other hazards require careful evaluation and 

selection of additional hazard-specific control measures. See the LOTO 

standard’s Final Rule, 54 Fed. Reg. 36657 (1989), for details. 

NOTE: It should be noted that turning off the engine with and removing the 

car key is not, strictly speaking, the same as applying a lockout or 

tagout device to an energy isolating device (EID) because neither the 

ignition switch, nor the key, are EIDs. See §§ 1910.147(b) and (d)(3)

for the energy isolating device definition and application of control 

provisions. Based upon the above preamble discussion, OSHA allows 

such alternative vehicle control measures in these limited 

circumstances only when the key removal fully ensures employee 

protection. 

As mentioned, given the unique circumstances associated with vehicle servicing 

and maintenance, turning off the engine and removing the ignition key may 

provide a significant degree of protection in many situations in which an 

employee is performing vehicle repair or maintenance. The authorized employee 

performing the repair or maintenance would need to retain sole control of the key 

(assuming the keyed switch is the only means of vehicle start-up). An additional 

precaution for the employee retaining the key would be to lock the doors. 

Although this control practice reasonably protects employees from inadvertent 

startup of the vehicle’s engine, it may not adequately control other energy sources 

that are independent of the ignition key subsystem. 
 3-24

These exclusive control practices, if incorporated into the energy control program, 

are feasible measures that significantly reduce the risk of exposure to the 

hazardous energy associated with the start-up of an internal combustion vehicle 

engine in situations in which a single individual is performing the servicing and/or 

maintenance work. However, although turning off the engine and retaining 

exclusive control of the ignition key may provide significant protection in some 

instances, there may be circumstances where there are other keys and/or other 

employees involved in the work activity. In situations such as these or when the 

work itself may activate the ignition circuit, additional measures are necessary to 

protect employees from hazardous energy exposures. 

For example, employees have been struck by and even run over by vehicles when 

the technician "shorted out" the ignition circuit, causing the vehicle to 

unexpectedly move. In another example, potential unexpected start-up hazards 

exist with older diesel engines because they could be "jump-started" by putting the 

vehicle in gear (without setting the brakes) and then simply pushing/rocking 

("budging") the vehicle enough to start it (with or without the ignition on). Thus, 

it is very important that the selected control measure(s) effectively protect 

exposed employees from all types of hazardous energy. 

D. Manufacturers’ Servicing and Maintenance Guidelines. It is essential for 

employers to consult with and incorporate specific vehicle manufacturer servicing 

and maintenance guidelines (e.g., operating manuals and bulletins) and other 

relevant materials to establish the hazardous energy control procedures. These 

manuals and materials often provide specific step-by-step instructions on how to 

safely perform servicing or maintenance tasks. [Refer to Section IX of this 

chapter for additional guidance regarding the use of generic energy control 

procedures and supplemental means, such as checklists and manufacturers' 

guidelines.] For example, the removal of an ignition key is not sufficient to 

protect employees from devices that may operate or activate independently of the 

ignition system. Thus, it may be necessary to disconnect the battery cable for 

some repair tasks, such as working on some cooling fans, which automatically 

start up even after the key has been removed. Likewise, air bags may 

inadvertently deploy and cause employee injury if the system is not properly 

controlled and residual energy dissipated before servicing or maintenance begins. 

NOTE: Employers, who meet manufacturers' servicing and maintenance 

guidelines, may be cited for a §1910.147 violation(s) if the 

manufacturer guidelines inadequately control the vehicle's energy 

sources and employee exposure exists to hazardous energy. 

E. “Troubleshooting,” Testing, and Component Positioning. There are 

circumstances when it is necessary to re-energize the vehicle or a component 

thereof to accomplish a particular task (e.g., diagnostic testing; maintenance 

troubleshooting; vehicle or component positioning). OSHA allows energization 

for testing or positioning purposes, as specified in §1910.147(f)(1), only for the 
 3-25

limited time during which it is necessary to test or reposition the vehicle or 

component. 

During these transition periods, employee exposure to hazards is high and a 

procedure needs to be developed to define the sequence of actions to accomplish 

the task safely. Under no circumstances is any part of an employee’s body ever 

permitted to be exposed within a hazardous area, such as the point-of-operation 

or in-going nip point area, during servicing and/or maintenance activities while 

the machine is running or energized. 

The use of supplemental safeguarding actions, such as personal protective 

equipment to protect against hot surfaces, use of a tarp(s) to shield a hot surface(s) 

or in-going nip point(s), safe work positioning, etc., must be used in conjunction 

with established procedures to protect the employee. 

F. References. Chapter 5 contains some useful references for the control of 

hazardous energy for vehicles that may be useful to Compliance Safety and Health 

Officers (CSHOs) in evaluating vehicle hazardous energy control. 

IV. Minor Servicing Exception to the Lockout/Tagout Standard. Activities such as 

lubrication, cleaning, un-jamming, servicing of machines or equipment, and making 

adjustments or tool changes are covered by the LOTO standard, if employees may be 

exposed to hazardous energy. However, some activities properly are classified as 

“servicing and/or maintenance” activities, but they are minor in nature and performed 

during normal production operations. Operations such as lubricating, draining sumps, 

servicing filters, making simple adjustments, and inspecting for leaks and/or malfunction 

are examples of routine servicing and maintenance activities, which often can be 

accomplished safely with effective production-mode safeguards, such as machine 

guarding methods consistent with the provisions of 29 CFR §1910, Subpart O. These 

servicing tasks do not require extensive disassembly of the machinery/equipment. 

Minor tool changes and adjustments, and other minor servicing operations, which take 

place during normal production operations, are not covered by this standard if they are 

routine, repetitive, and integral to the use of machines or equipment for production, and if

work is performed using alternative protective measures which provide effective 

employee protection. See the 29 CFR §1910.147(a)(2)(ii) note. LOTO is not required 

when each of these elements exists and employees may perform servicing and 

maintenance activities with the machine or equipment energized. 

However, activities requiring machine or equipment shutoff and disassembly, 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. For example, the changing of an abrasive grinding wheel takes place outside 

of the normal production process: the machine is turned off, grinding operations stop, a 
 3-26

guard is removed, and the wheel retainer nut is loosen and removed. Therefore, the 

§1910.147(a)(2)(ii) minor servicing exception does not apply to this operation. 

NOTE: OSHA issued a citation alleging a serious violation of §1910.147(c)(1) 

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. 

 The Occupational Safety and Health Review Commission (OSHRC) rejected 

an employer's assertion that set-up activities associated with this equipment 

constituted minor servicing within the scope of the §1910.147(a)(2)(ii) 

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. 

 

The Commission stated that work performed before the normal production 

operation is not covered by the exception. The Commission further concluded 

that setting up does not occur during normal production operations, and 

therefore, setting up, by definition, cannot fall within the exception to 

§1910.147(a)(2)(ii). See Westvaco Corporation, 16 BNA OSHC 1374 

(Docket No. 90-1341, 1993). 

Furthermore, the replacement of machine or equipment components -- such as belts, 

valves, gauges, linkages, support structure, etc. -- normally is not considered a routine 

maintenance function that can be safely accomplished when a machine or piece of 

equipment is operating. These types of activities need to be performed in accordance 

with the requirements of the LOTO standard. In addition, any servicing and/or 

maintenance activity, which takes place during the machine’s or equipment’s normal 

production operation, is covered by the LOTO standard if employee exposure to 

hazardous energy (e.g., employee bypasses a guard; placement of a body part into a 

machine danger zone) exists. See §§ 1910.147(a)(2)(ii)(A) and (B). 

 

In short, the general rule is that servicing and/or maintenance must be performed under 

LOTO requirements. However, the LOTO standard is not intended to cover certain minor 

servicing activities, which are necessary to carry out the production process, provided that 

all of the criteria detailed in the exception are met. Nonetheless, the exclusion from 

LOTO does not mean that the employer can avoid providing employee protection even 

though employees carry out these minor servicing tasks with the machine or equipment 

energized. Rather, in order to take advantage of the limited exception, an employer must 

provide effective alternative protection in lieu of LOTO. 
 3-27

NOTE: The American National Standard on the Control of Hazardous Energy - 

Lockout/Tagout And Alternative Methods (ANSI/ASSE Z244.1-2003; 

Foreword), recognize[s] the broader universe of hazardous energy control, 

... [and] addresses the need for greater flexibility through the use of 

alternative methods based on risk assessment and application of the hazard 

control technology. This standard employs a decision matrix (Figure 1) and 

policy (e.g., Section 5.3.10: Special applications; Section 5.4: Alternative 

methods) that allow employers to use alternative protective methods in 

situations where OSHA standards require employers to lockout or tagout an 

energy isolation device. When an OSHA standard prescribes a practice, 

design, or method that provides a requisite level of employee protection, 

employers may not adopt an alternative approach (e.g., use of control circuitry 

when the standard requires the use of an energy isolation device) that provides 

a lower level of employee protection. The ANSI Z244.1-2003 standard does 

not affect the employer's obligation to comply with all provisions of the LOTO 

and related hazardous energy control standards, including the obligation to use 

energy isolation devices, unless the standards permit alternative methods to 

control hazardous energy. 

 

The first set of criteria for determining the application of the minor servicing exception is 

whether the activity must take place during, and is inherent to, normal production 

operations. These servicing activities must be necessary to allow production to proceed 

without interruption. Additionally, the minor servicing activity must be: 

A. Routine: The activity must be performed as part of a regular and prescribed 

course of procedure and be performed in accordance with established practices. 

B. Repetitive: The activity must be repeated regularly as part of the production 

process or cycle. 

C. Integral: The activity must be inherent to the production process. 

The employer must also demonstrate that the alternative measures provide effective 

protection from the hazardous energy. Most importantly, this exception applies only if

each and every element of the exception is met. 

Several alternative means for providing effective protection from the hazardous portion of 

machines and equipment are presented by the national consensus standard, ANSI B11.19-

1990, which addresses performance criteria for the design, construction, care, and 

operation for machine tool safeguarding. The Performance Criteria for Safeguarding, 

ANSI B11.19-2003, consensus standard for machine tools, superseded the 1990 edition, 

and it also contains requirements for the design, construction, installation, operation, and 

maintenance of the safeguarding used to eliminate or control hazards to individuals 

associated with machine tools. Although these standards are not all-inclusive, they 

describe effective safeguarding alternatives for the protection of employees. Some of 

these described safeguards include: 
 3-28

A. Interlocked barrier guards, 

B. Presence sensing devices, and 

C. Various devices under the exclusive control of the employee. 

Such guards or safety devices, when 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 §1910.147(a)(2)(ii) exception criteria. During minor 

servicing, an employer is considered to have met the requirement for providing effective 

alternative protection by the use of special tools or guarding (safeguarding) techniques 

that effectively prevent employee exposure to hazardous energy. 

NOTE: In order for the control measure to be considered an effective and properly 

applied technique, the selection and use of alternative method(s) must be 

based on generally accepted good engineering practices (e.g., applicable 

manufacturers' design, maintenance, inspection, testing and operation 

recommendations; prior operating experience; reliability data). As an example 

of recognized and generally accepted good engineering practice, barrier guard 

interlock devices are specifically designed (e.g., increased reliability of 

operation; anti-bypass capabilities) and constructed for use in safeguarding 

applications. The improper application of a safety interlock component on a 

machine or piece of equipment would not constitute recognized good 

engineering practice and would not constitute effective alternative protection. 

To better illustrate effective alternative protection based on recognized good engineering 

practices, a circuit that meets the control reliability and control-component-failureprotection requirements of the American National Standards Institute standard, ANSI 

B11.19-1990 [for Machine Tools – Safeguarding When Referenced by the Other B11 

Machine Tool Safety Standards – Performance Criteria for the Design, Construction, 

Care, and Operation], would provide alternative safeguarding measures with respect to 

the minor servicing exception if these devices are under the exclusive control of the 

employee performing the minor servicing. It is important to apply this safeguard through 

a hazard analysis process on a case-by-case basis in order to ensure that it, in fact, 

provides equivalent and effective employee protection. 

For example, in order for the clearing of a conveyor package jam to meet the criteria for 

the “minor servicing” exception, an employer must adopt alternative measures that 

provide effective protection in order to avoid the requirements contained in 29 CFR 

§1910.147. A CSHO should consider all of the steps taken by an employer to provide 

alternative, effective protection (e.g., training, disciplinary provisions, engineering 

controls, start-up alarms/delays, administrative provisions, near miss and related-injury 

data, etc.) in order to ascertain whether the alternative, including all of its steps, reliably 

prevents an employee from being injured by hazardous energy when performing servicing 

and maintenance activities under the “minor servicing” exception. 
 3-29

NOTE: Generally, the party claiming benefit of an exception bears the burden of 

proving that the scenario falls within that exception. See Falcon Steel Co., 16 

BNA OSHC 1179 (No. 89-2883, 1990). Thus, 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. 

 If the CSHO documents a LOTO violation and believes that the employer’s 

minor servicing exception assessment is in error, then she needs to develop a 

list of specific inadequacies associated with one or more elements of the 

exception. This will allow OSHA to be able to refute an employer’s 

contention that the LOTO standard does not apply because of the 

1910.147(a)(2)(ii) exception. One way for a CSHO to confirm that the minor 

servicing exception is inapplicable is to document specific facts (e.g., injury 

experience) showing that the alternative work procedure does not provide 

effective employee protection in that: 1) a possibility for employee injury 

exists; and/or 2) employees have been injured. This evidence should be 

developed in conjunction with evidence demonstrating that the energy to 

which employees are exposed is hazardous. 

To further illustrate the alternative methods of protection, with respect to the minor 

servicing exception, the following examples are provided. Each of the following 

examples addresses only the effectiveness of alternative protection and presumes the 

existence of all other elements in the minor servicing exception. 

A. Some tool changes and adjustments, such as changing a mixing blade on a vertical 

mixer or a drill bit on a single-spindle drill press or a carbide cutting tool on a 

single-spindle automatic screw machine, are permitted to be performed without 

LOTO if the 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. 

NOTE: The use of control circuit devices does not, in all cases, protect 

employees from stored or residual energy hazards. Also, for purposes 

of this exception, control circuit devices may not provide alternative 

effective protection if any of the above criteria are not met or if injury 

experience exists confirming the procedure’s inadequacies. 

B. A simple task on an automatic chucking machine, for example, may involve 

adjusting coolant flow or the resetting the tool holder to a position that would 

result in a dimensionally accurate finished work piece. In these and other similar 

cases where the employee must negate the effectiveness of the safeguards or 
 3-30

otherwise expose himself to the hazardous energy, the machine operator would 

need to shut off the switch and have exclusive control of the on/off switch or local 

disconnect switch. 

C. Vertical and horizontal milling machine operators perform minor tool changes and 

minor adjustments (e.g., minor belt drive adjustments; moving the coolant hose 

assembly close to the point of operation) that are integral to the production process 

by pushing the machine's stop button (without disconnecting the power supply to 

the machine) and perform the task in the close proximity of the start button. All 

that is required to restart the machine is to push a guarded start button; however, 

an operator has exclusive control of this shut off control circuit because he could 

easily see another person approaching the control panel and prevent her from 

operating the control. In this scenario, milling machine operators who shut off the 

machine and exercise exclusive control over this control circuit would not need to 

implement LOTO. However, the minor servicing would be covered by the LOTO 

standard if the alternative work method becomes ineffective (i.e., there is no 

alternative employee protection) and exposes employees to machine hazards. 

In a similar example, if it becomes necessary to adjust the movement of a longbed milling machine worktable and the isolating hydraulic cut-off valve is not in 

the exclusive control of the person making the adjustment, or this requires the 

employee to negate the effectiveness of the safeguards so that the employee is 

exposed to the hazard of the machine (i.e., there is no alternative protection), the 

LOTO standard applies. However, if this step is performed without the employee 

having to remove or bypass any safeguards or otherwise expose her body to the 

hazardous area of the machine, the LOTO standard does not apply. Refer to the 

August 24, 2005 letter to Lockton Companies of St. Louis for additional detail. 

D. Blow mold machine operators perform minor un-jamming tasks, during normal 

production operations, at the machine’s trimmer unit on a routine and repetitive 

basis to remove stuck plastic containers. This operator shuts the machines off 

with the control circuit switch (stop button) and she opens an interlocked plexiglass barrier guard to gain access to the trimmer’s point-of-operation area. The 

employer utilizes a guard system, designed by the manufacturer in accordance 

with recognized and generally accepted good engineering practices, that causes the 

mechanical interlock switch to break the electric circuit when the guard is moved 

for employee access purposes and shuts down the machine. Within the context of 

the minor servicing exception, the described and properly applied interlocked 

plexi-glass guard system, together with the operator’s exclusive control of the 

control circuit devices, constitute alternative measures which constitute effective 

protection. 

E. The removal of a part that is stuck (jammed) in a plastic injection molding 

machine may not require de-energization and LOTO of the entire machine. Once 

the machine has completed a cycle and is shut-off (using the stop push button), 

opening the interlocked sliding operator gate guard prevents the machine from 
 3-31

cycling until the operator repositions the guard and intentionally starts up the 

machine. Similarly, when an operator stops a machine by using the stop/start 

controller, the use of interlocked movable guards, which prevent activation of the 

machine while the guard is not in place, provides effective alternative protection 

as long as: 

1. The employee is positioned such that the interlock operator-gate and rear-gate 

guards provide the employee(s) with sufficient protection (e.g., an interlock 

gate guard is not adequate protection if the employee's entire body is inside the 

guard area); 

2. Injection molding machine safety systems are designed, inspected, tested, 

maintained, and operated in accordance with recognized and generally 

accepted good engineering practices (e.g., per the manufacturer's instruction); 

and 

3. Means of control of the machine remain in the exclusive control of the person 

afforded the protection. 

These precautions are necessary to ensure that the gate guards do not accidentally 

close causing the machine to start-up while the employee is inside the machine 

and to ensure that no other person can restart the machine without the knowledge 

and consent of the person performing the minor servicing. 

Alternatively, LOTO would be required if the stuck part or other condition creates 

a situation where each and every element of the minor servicing exception cannot 

be met. For example, a mold may open too soon or a stuck plastic part may melt 

or the part may become stuck such that LOTO is required because “other-thanminor” cleaning (e.g., prying, pulling, scrapping, and/or chipping) or even 

machine component (e.g., die) disassembly, must be performed. These types of 

activities are not minor in nature. 

F. In the printing industry, which employs printing presses, binding and finishing 

equipment, the following tasks were identified as examples of minor servicing 

activities commonly performed during normal production operations: 

1. Clearing of certain types of paper jams; 

2. Minor cleaning, lubricating, and adjusting operations; 

3. Certain plate and blanket changing tasks; and 

4. In some cases, paper webbing and paper roll changing. 

NOTE: As described in the §1910.147 (a)(2)(ii), employers can use effective 

alternatives to lockout/tagout only in the limited circumstances 

outlined in the exception. Not all make-ready activities in the printing 

industry meet each element specified in the minor servicing exception. 

For example, some inch buttons on the inch-safe-service systems are 

located so that an employee can inch the press rolls and simultaneously 

access the unguarded danger area at the roller's ingoing nip point. 

Thus, this alternative method would not constitute effective employee 

protection and lockout/tagout provisions would apply in this scenario. 
 3-32

The inch-safe-service technique, used in conjunction with the main drive control, 

appeared to provide effective alternative protection for these minor servicing 

activities. This technique is consistent with the use of controls specified in the 

American National Standards B65.1 (1985) and B65.2 (1988) for web and sheet 

fed printing presses for which, as a minimum, a stop/safe/ready function must be 

available at the designated control stations. On presses attended by more than one 

employee, or when it is possible for one employee to enter the frame or to be 

obscured from view of another employee, other reliable and effective protective 

mechanisms also must be employed in conjunction with work procedures and 

training to achieve effective alternative protection to LOTO. 

Refer to the September 16, 1992 and April 7, 2004 letters to the Printing 

Industries of America, Inc. for additional details.

G. The automotive industry designs some processes with Monitored Power System 

(MPS) control systems meeting the control reliability and control component

failure protection requirements of the American National Standards for machine 

tools (ANSI B11.19-1990) and manufacturing systems/cells (ANSI B11.20-1991). 

Although control circuits are not energy isolating devices, as defined by the 

standard, the use of MPS which meet the above referenced ANSI standards would 

provide effective safeguarding alternative methods, which constitute effective 

alternative protection. Thus, such an MPS may be used to protect employees who 

are performing minor tool changes and adjustments, and other minor servicing 

activities, which take place during normal production operations, provided that 

other remaining elements of §1910.147(a)(2)(ii) exception are met. Refer to the 

December 16, 1999 letter to the UAW/General Motors Department for additional 

details. 

V. Protective Materials and Hardware. Paragraphs 1910.147(c)(5)(i) and (ii) describe 

protective materials and hardware (e.g., locks, chains, tags and their means of attachment) 

required under the LOTO standard. The standard also requires that, when lockout or 

tagout devices are used, they must be the only devices used in conjunction with energy 

isolating devices to control hazardous energy. They must be provided by the employer, 

be singularly identified, and not be used for other purposes. In addition, they must meet 

the following criteria. 

A. Durable. LOTO devices must be durable enough to withstand conditions in the 

workplace environment. Tagout devices must not deteriorate or become illegible, 

even when used in conjunction with corrosive components such as acid or alkali 

chemicals or in wet environments. 

B. Standardized. LOTO devices must be standardized according to color, shape, or 

size. Tagout devices also must be standardized according to print and format. 

Tags must be legible and understandable by all employees. Tags must warn 

against hazardous conditions if the machine is energized, and offer employees 
 3-33

clear instruction such as: “Do Not Start,” “Do Not Open,” “Do Not Close,” “Do 

Not Energize,” or “Do Not Operate.” 

C. Substantial. Protective materials and hardware must be substantial enough to 

minimize the likelihood of early or accidental removal. Other than using a key or 

combination to remove a lock, employees must be able to remove locks only by 

using excessive force with special tools, such as bolt cutters or other metal-cutting 

tools. 

Additionally, the lockout device must be substantial enough to prevent removal 

without the use of unusual techniques. For example, the use of nylon cable ties 

would not be an appropriate substitute for more traditional and substantial lockout 

devices, such as the use of locks and chains to hold a valve in the safe position. 

While a cable tie is a positive means of holding the energy isolating device in a 

safe position, nylon ties are generally removable through the use of common 

cutting tools (e.g., pocket knives, side cutters, or scissors) or by releasing the pawl 

mechanism with a device such as screwdriver; neither of which constitutes an 

“unusual technique,” as required by the standard. 

NOTE: An employer using machines capable of being locked-out could, 

however, use the cable ties as part of a tagout system consistent with 

1910.147(c)(5), as long as the use of the tagout system provided full 

employee protection, (e.g., double-block and bleed arrangement with a 

tag, using a nylon cable tie as a means of attachment) as set forth in 

1910.147(c)(3). 

Tag attachments, used to attach the tag, must be non-reusable, self-locking, and 

non-releasable, with a minimum unlocking strength of 50 pounds. Tags must be 

attachable by hand, and the device for attaching the tag should be a one-piece 

nylon cable tie or its equivalent so it can withstand all environments and 

conditions. 

D. Labeling. LOTO devices must be labeled to identify the specific employees who 

are authorized to apply and remove them. As a result, the authorized employee 

who is identified will be given greater assurance that other employees know of her 

involvement in the work activity and that only she will be allowed to remove the 

device(s). This user identification provision also provides an additional degree of 

accountability to the overall program. It enables the employer to inspect the 

application of energy control procedures and to determine which employees are 

properly implementing the procedure. If lockout and tagout devices are not being 

properly attached, for example, identification on the devices will enable the 

employer to locate the non-complying employee(s) and correct the problem 

promptly. 

VI. Energy Isolating Devices. The entire LOTO standard is predicated on the practices and 

procedures that are necessary to disable and isolate machines or equipment from 
 3-34

hazardous energy. The employer’s primary tool for providing protection under the 

standard is the energy isolating device, which is the mechanical device that physically 

prevents the transmission or release of hazardous energy. [See §1910.147(b) and Chapter 

1, Section IX.H for the definition.] 

NOTE: With respect to the definition of Energy isolating devices, not all line valves 

effectively and reliably prevent the transmission or release of hazardous 

energy. Manufacturer valve design information and application 

recommendations may aid Compliance Safety and Health Officers (CSHOs) in 

determining whether a specific line valve installation meets the performanceoriented requirements for energy isolating devices with respect to recognized 

good engineering practice. 

Excess flow valves, excess flow check valves, and check valves are examples 

of some types of line valve designs that do not, in all cases, effectively and 

reliably isolate hazardous energy (e.g., check valves can open and close 

automatically with changes in line pressure, check valves may leak materials 

due to mechanical problems like sticking in the open position, etc.). Further, 

energy isolating devices installed after January 2, 1990 must be designed to 

accept a lockout device and, in some cases (e.g., excess flow valves without 

manual shutoff valves), these types of valves are not capable of being locked 

out. See §§ 1910.147(b) and (c)(2)(iii). 

There are two categories of energy isolating devices: those capable of being locked out 

and those that are not. When the system is capable of being locked out, the more reliable 

means to isolate energy is to use lockout devices to hold the energy isolating device in a 

safe position, rather than using a prominent warning (tagout) device. The tagout device 

alerts employees to the hazard of re-energization and states that employees may not 

operate the machinery to which it is attached until the tag is removed in accordance with 

an established procedure, but it provides less protection (than a lockout device) against 

premature/improper removal. 

A. Capable of Being Locked Out. If an energy isolating device can be locked out, the 

employer must use a lockout program unless the employer develops, documents, 

and utilizes a tagout program that provides employees with a level of safety 

equivalent to that of a lockout program. (See Chapter 3 Section VII for details.) 

An energy isolating device is considered “capable of being locked out” if it meets 

one of the following requirements: 

1. Is designed with a hasp or other part to which a lock can be attached (e.g., a 

lockable electric disconnect switch); 

2. Has a locking mechanism built into it; or 

3. Can be locked without dismantling, rebuilding, or replacing the energy 

isolating device or permanently altering its energy control capability (such as 

using a lock/chain assembly on a pipeline valve, a lockable valve cover, 
 3-35

circuit breaker lockout, or fuse block-out devices). 

Equipment that accepts bolted blank flanges and bolted slip blinds are considered 

to be capable of being locked out. 

B. Not Capable of Being Locked Out. Sometimes it is not possible to lock out the 

energy isolating device associated with the machinery. In that case, authorized 

employees must securely fasten a tagout device as close as safely possible to the 

energy isolating device in a position where it will be immediately obvious to 

anyone attempting to operate the device. The employer also must meet all of the 

tagout provisions of the standard. 

Equipment or machines ordered or purchased after January 2, 1990, and older 

equipment which undergoes extensive replacement, repair, renovation, or 

modification must be provided with lockout capability, if such a design is feasible. 

It is anticipated that the designing of lockout capability will encourage employers 

to utilize lockout devices in their energy control programs, rather than relying on 

tagout. Although there is no requirement in the standard to retrofit pre-1990 

machines or equipment that have not undergone the described restoration, an 

employer nevertheless may choose to modify or replace the applicable energy 

isolating device(s) to make it capable of being locked out. 

NOTE: OSHA does not enforce the standard with respect to the 

designer/manufacturer of the machine or equipment. However, when 

the designer/manufacturer is functioning as an employer, the 

designer/manufacturer has the same obligations as other employers to 

provide the protections for its own employees that are required by the 

LOTO standard. 

VII. Lockout vs. Tagout. The physical protection offered by the use of a lock, when supported 

by the information provided on a tag used in conjunction with the lock, provides the 

greatest assurance of employee protection from the release of hazardous energy. Lockout 

and/or tagout devices used to protect employees from hazardous energy must be 

implemented as part of a comprehensive program of energy control. 

The following descriptions address the employer’s options and limitations with regard to 

the use of lockout versus tagout programs. 

A. Tagout. Tagout must be used where the energy control device cannot accept a 

lock. In this situation, the employer’s energy control program for these 

unlockable pieces of equipment and machines must utilize a tagout program that 

complies with all tagout-related provisions of the standard. 

NOTE: Refer to the preceding Capable of Being Locked Out discussion, which 

explains that some isolating devices may be locked out through 

external means, such as by using circuit breaker lockout devices or 
 3-36

attaching a chain and lock assembly to lockout valves. 

The §1910.147(c)(3) Full Employee Protection requirements do not 

apply to equipment or machines with non-lockable isolating devices. 

Because a tagout program does not involve positive restraints on energy control 

devices, it requires constant vigilance to ensure that: 1) the tags are properly 

applied [See §1910.147(d)(4)(iii)]; 2) the tags remain affixed throughout the 

duration of the servicing or maintenance job; and 3) no employee violates the tag 

by re-energizing the machine or equipment, either intentionally or inadvertently, 

before the tag is removed. 

FACE Report No. 94-10: Journeyman Wireman Electrocuted After 

Contacting Energized Switchgear Components at Power Plant - West 

Virginia [http://www. cdc.gov/niosh/face/In-house/full9410.html]. A 53-

year-old journeyman wireman was electrocuted when he contacted two 

energized, 6.9 -kilovolt bus†

 terminals. The victim and two coworkers (all 

contract employees) were installing electrical components of a sulfur 

dioxide emission control system in a 14-compartment switch house. 

†

A conducting bar, rod, or tube that carries heavy currents to supply several electric 

circuits. 

The circuit breaker protecting the internal bus within the switch house had 

been tripped out and marked with a tag—but it had not been secured by 

locking. This procedure was consistent with the hazardous energy control 

procedures of the power plant. 

The victim and his coworkers were wiping down the individual 

compartments before a pre-startup inspection by power plant personnel. 

Without the knowledge of the victim and his coworkers, power plant 

personnel had energized the internal bus in the switch house. When the 

victim began to wipe down one of the compartments at the south end of 

the switch house, he contacted the A-phase bus terminal with his right 

hand and the C-phase bus terminal with his left hand. This act completed 

a path between phases, and the victim was electrocuted. 

A coworker walking past the victim during the incident was blown 

backward by the arcing and received first-degree flash burns on his face 

and neck. A second coworker at the north end of the switch house heard 

the explosion and came to help. He notified the contractor's safety 

coordinator by radio and requested EMS. The EMS responded in about 15 

minutes and transported the victim to a local hospital emergency room 

where he was pronounced dead [NIOSH 1994]. 

As the accident description indicates, tagout devices do not serve as positive 
 3-37

restraints and only warn employees that the machines or equipment are not to be 

re-energized. The additional tagout device requirements in the standard are based 

on the fact that the effective use of tagout relies on the involvement of all 

employees in the facility and on employee knowledge, including employees' 

respect for the tagout device limitations. [See §§ 1910.147 (c)(6)(i)(D) and 

1910.147(c)(7)(ii)(A-F), respectively.] 

Nonetheless, employee safety does not reside in a specific device, whether a tag or 

lock; instead, safety lies in a comprehensive program that includes the use of 

controls, good procedures and careful training combined with the assurance of 

accountability. If these principles are in place and the employer complies with the 

other tagout-related requirements of the standard, a system that uses tags will 

adequately protect employees. 

B. Lockout and Full Employee Protection [Tags Plus]. Lockout is a more effective 

means of ensuring the de-energization of equipment; it is the preferred method 

because lockout-based safety programs are less susceptible to human error, and 

tagout devices have inherent physical limitations. 

Therefore, if the energy isolating device is capable of being locked out, the 

standard requires lockout unless the employer can demonstrate that a tagout 

system will provide Full Employee Protection ("Tags Plus") -- i.e., a level of 

protection that is equivalent to that provided by lockout. See 29 CFR 

§1910.147(c)(2)(ii). In order for the employer to demonstrate that a tagout 

program is as protective as a lockout program for a lockable piece of equipment or 

machine, that employer will need to show additional elements which bridge the 

gap between lockout and tagout. It is permissible for employers to implement a 

tagout program provided that all applicable full employee protection requirements 

are met. 

The term Full Employee Protection is set forth in §1910.147(c)(3), and it requires 

compliance with all tagout-related provisions of the standard, which includes 

attaching the tagout device at the same location that the lockout device would 

have been attached. Also, as explained in the preceding section on “Tagout,” 

inherent tagout program limitations necessitate the implementation of additional 

program and specification requirements when an employer opts to use a tagout 

program instead of a lockout program. 

A key element in demonstrating that the tagout program provides equivalent 

protection to a lockout program is the standard's provision that the tagout program 

provide at least one additional safety measure. In other words, at least one added 

safety measure must be used in addition to tagging the energy isolation device to 

prevent unexpected re-energization. This independent, additional measure is 

designed to protect an employee from injury or death through the inadvertent 

activation of an energy isolating device associated with human error, inadvertent 
 3-38

contact, the loss or detachment of a tag, or from any other limitation of tags. Such 

additional safety measures might include the: 

1. Closure of a second in-line valve (e.g., double block and bleed); 

2. Removal of a valve handle to minimize the possibility that machines or 

equipment might be inadvertently energized or started; 

3. Removal of an additional isolating circuit element (e.g., fuse); 

4. Opening of an extra disconnecting device (e.g., disconnecting switch; circuit 

breaker); 

5. Opening and then racking out a circuit breaker; 

6. Grounding of an electrical circuit, if the grounding practice would protect the 

employee if the tagged isolating device were operated; or 

7. Locking, blocking, or barricading a controlling switch. 

Any additional control measure ("Tags Plus") must be integrated into an energy 

control program through sound hazard-specific analyses on a case-by-case basis. 

For example, the blocking of a control switch as an additional measure to tagging 

an electrical disconnect may be an effective second layer of protection for 

preventing the mechanical activation of a machine, but this block may be an 

inadequate "Tags Plus" measure for the same machine's hydraulic or pneumatic 

hazardous energy sources. 

These independent control measures, when effectively incorporated into the 

employer’s energy control program and enforced through regular supervision, 

provide employees with an independent, redundant control measure. In short, this 

additional control measure provides the authorized employee using a tagout 

program with a “second layer of protection” in the event the tagout device for the 

primary isolating device is defeated. 

NOTE: While describing additional protective means similar to those listed in 

§1910.147(c)(3)(ii), the American National Standard on the Control of 

Hazardous energy – Lockout/Tagout And Alternative Methods 

(ANSI/ASSE Z244.1-2003; Section 5.3.1) requires the user to 

demonstrate that the TO program provides an effective level of safety

whereas paragraph (c)(3) requires the employer to demonstrate that the 

tagout program will provide a level of safety equivalent to that 

obtained by using a lockout program (emphasis added).

VIII. Notification of Affected Employees. Lack of information regarding the status of the 

machine or equipment could endanger both the servicing or maintenance employees and 

the employees who re-energize, operate or work around the machines or equipment. 

Whenever LOTO control might directly affect another employee’s work activities, 

paragraph (c)(9) requires the employer or authorized employee to notify the affected 
 3-39

employees prior to applying, and after removing (but before a machine or piece of 

equipment is started), a lockout or tagout device from a machine or piece of equipment’s 

energy isolating device(s). 

Such notification informs affected employees of the impending interruption of the normal 

production operation and reinforces the importance of the restrictions imposed on them 

by the energy-control program. In addition, this essential program requirement ensures 

that employees do not unknowingly attempt to reactivate a machine or piece of equipment 

after an authorized employee has isolated its energy source and rendered it inoperative. 

Conversely, employees need to know when control measures have been removed. This 

notification of employees, after removing a LOTO device from an energy isolating 

device(s), alerts them that the machine and equipment are capable of being started-up or 

operated. Without this information, employees might mistakenly believe that a system is 

safe to continue working around when, in fact, it is not. 

IX. Energy Control Procedures. Energy control procedures are the cornerstone of the LOTO 

standard because they provide employees the guidance necessary to effectively and safely 

control hazardous energy when they service or maintain machinery or equipment. The 

requirement to develop procedures is performance-oriented, but ultimately the procedures 

must explain what employees must know and state what steps employees must take to 

effectively and safely control hazardous energy during the servicing/maintenance 

activities. 

It is essential for Compliance Safety and Health Officers (CSHOs) to evaluate an 

employer's energy control procedures to determine whether each procedure provides 

enough detailed information and guidance for an authorized employee to understand how 

to safely and effectively utilize energy control measures when servicing each machine 

covered by the procedure. If an associated hazard is discovered because the energy 

control procedure provides insufficient information (e.g., procedure over-generalization), 

then the CSHO must document the alleged §1910.147 violations in accordance with 

Chapter 2, Section III of this policy manual. The following policy and guidance are 

provided to help CSHOs evaluate employers' energy control procedures. 

NOTE: Energy control procedures and employee training are distinct and independent 

elements in an employer’s energy control program. Section 1910.147(c)(4)’s 

minimum requirements for procedural detail and specificity may not be 

diminished by employee training programs that exceed the requirements of 

§1910.147(c)(7). In short, additional training does not supplement and correct 

an inadequate procedure. Regardless of the amount and type of employee 

training, a procedure must provide sufficient detail and specificity to permit an 

authorized employee to safely and effectively utilize energy control measures 

to service/maintain each machine or piece of equipment covered within the 

scope of the procedure. 

 

Paragraph (c)(4) provides that employers must develop, document, and utilize procedures 

for the control of potentially hazardous energy, and that the procedures must clearly and 
 3-40

specifically outline the steps to be followed, techniques to be used, and measures to be 

applied by the employer to ensure that the procedure is used. 

Specifically, 29 CFR §1910.147(c)(4)(i) states: 

Procedures shall be developed, documented, and utilized for the control of 

potentially hazardous energy when employees are engaged in the activities 

covered by this section. 

A procedure, at a minimum, must contain enough detail for authorized employees to have 

a clear understanding of the energy control measures so that they may follow the 

procedural steps associated with a machine LOTO to effectively control all types and 

forms of hazardous energy. Due to the number of variables in controlling hazardous 

energy and the need for employees to follow the specified control steps, a documented 

(written) energy control procedure is necessary in most situations. However, there are 

limited situations, specified in the paragraph 1910.147(c)(4)(i) exception note, where the 

procedure documentation is not necessary for a specific machine or piece of equipment. 

This exception is intended to apply to situations in which the LOTO process can take 

place without detailed interactions of energy sources, machines/equipment, and 

employees. 

For example, a motor in a shop may be wired to an electrical disconnect. The authorized 

employee can isolate the motor from the electric energy source and lock it out, using her 

personal lockout device on the disconnect switch in accordance with the procedures set 

forth in the standard. If this scenario meets each of the following elements, which are 

contained in the documentation exception, the procedure would need to be developed and 

utilized, but it would not need to be documented: 

A. There is a single source of hazardous energy that can be easily identified and 

isolated, and there is no potential for stored or residual energy in the machine; 

B. The isolation and locking out of that single energy source will totally de-energize 

and deactivate the machine; 

C. A full lockout of the energy source is achieved by a single lockout device, which 

is under the exclusive control of the authorized employee performing the 

servicing; and

D. The servicing, while the machine is locked out, cannot expose other employees to 

hazards. 

However, procedure documentation becomes necessary if an accident involving 

hazardous energy occurs (in utilizing this exception) because such an occurrence 

indicates the need for more formal treatment of the energy control procedure. 

NOTE: The Hazardous energy control procedures section of the American National 

Standard on the Control of Hazardous Energy - Lockout/Tagout And 

Alternative Methods (ANSI/ASSE Z244.1-2003; Section 5.3.1.1), which 

contemplates an exemption from the obligation to develop written energy 
 3-41

control procedures, differs from the OSHA exemption [note to 

§1910.147(c)(4)(i)]. The consensus standard does not affect the requirement 

that an employer meet each of the eight conditions listed in the note to § 

1910.147(c)(4)(i) to take advantage of the exception to document an energy 

control procedure. 

In order to ensure that employers develop energy control procedures with sufficient

specificity to permit employees to effectively and safely control hazardous energy, 

paragraph (c)(4)(ii) of the standard defines the minimum elements for the procedure. The 

energy control procedures must clearly and specifically outline the scope, purpose, 

authorization, rules, and techniques that will be used to control hazardous energy sources, 

as well as the means that will be used to enforce compliance. At a minimum, these 

procedures must also include the following elements: 

A. A specific statement of the intended use of the procedures; 

B. The specific procedural steps for shutting down, isolating, blocking and securing 

machines or equipment to control hazardous energy [See also §§ 1910.147(d)(2), 

(d)(3) and (d)(5)]; 

 NOTE: It is imperative that the employee who is to perform the servicing (who 

must utilize the energy control procedure) understands the hazards of 

the work and knows how to control the hazardous energy. It is for this 

reason that paragraph (d)(1) requires that, before the machine is even 

turned off, the authorized employee must have the knowledge of the 

type and magnitude of energy, the hazards associated with the energy 

to be controlled, and the method or means to be used to control the 

energy. 

C. The specific procedural steps for the placement, removal (including, if 

contemplated by the employer and permitted by §1910.147(e)(3), the specific 

procedure for the LOTO device removal by someone other than the authorized 

employee who applied it), and transfer of lockout or tagout devices and the 

responsibility for them [See also §§ 1910.147(d)(4), (e), (f)(3) and (f)(4)]; and 

NOTE: Area Directors shall cite the §1910.147(f)(1) sequence of step 

requirements, and not the paragraph (c)(4) provisions, when an 

employer fails to develop or utilize procedures to safely test or position 

machine/equipment component(s) in conjunction with servicing and 

maintenance activities. 

D. The specific requirements for testing a machine to determine and verify the 

effectiveness of LOTO devices and other control measures [See also 

§1910.147(d)(6)]. 

NOTE: The ANSI Z244.1-2003 standard’s provisions for hazardous energy 
 3-42

control procedures contain procedure element criteria that, while 

conceptually valuable, do not explicitly mandate all of the minimum 

requirements that are prescribed in §1910.147(c)(4)(ii). While the 

consensus standard and annexes provide valuable guidance and tools 

(e.g., sample energy control procedures; sample lockout/tagout 

placarding methods) to assist employers in developing specific methods 

to meet their procedural obligation under the LOTO standard, 

employers ultimately must develop energy control procedures that 

conform to the provisions of §1910.147(c)(4)(ii). 

OSHA used the word specific in the standard to describe the elements of the procedure. 

This was done to emphasize the need for detailed procedures because over-generalization 

does not provide authorized employees sufficient information to effectively control the 

hazardous energy to which they are exposed. The amount of detail in an employer's 

procedure will depend upon the complexity of the machine or piece of equipment and the 

information that the authorized employee must know to safely control the hazardous 

energy for the machine throughout the course of the servicing operation. 

Thus, a written energy control procedure need not be complicated and detailed, if the 

system to be controlled is not complex or does not require unusual control measures. For 

example, a written procedure could be very simple if there is a machine with a single 

energy source that must be serviced and the means to shut down and isolate the machine 

is uncomplicated and apparent – e.g., pushing a stop button, notifying affected employees 

of the LOTO, opening and locking out an electric switch (which is at the machine), and 

pressing the start button to verify machine isolation (assuming a residual energy hazard is 

not present). 

NOTE: It should be noted that a small business does not necessarily have simple 

energy control issues. Complex machinery and equipment can be found in 

workplaces with few employees, especially in highly-automated operations. 

From the standpoint of safety, there is no basis for concluding that a small 

employer is inherently less likely to need a detailed written procedure than a 

large employer. Thus, the performance oriented requirements for written 

procedures are appropriate for all employers, regardless of size. 

In some instances where control measures are not readily apparent or require specific 

instruction, the energy control procedure may need to specify the types, location and/or 

operating instructions for the machine operating controls or it may need to specify the 

types, location and/or operating instruction for energy isolating devices in order to ensure 

that employees have the information necessary to safely turn off and effectively deenergize a machine. 

NOTE: Any method of identification (e.g., by machine type and location or by 

machine type and model number) that enables an authorized employee to 

determine which energy control instructions, operating controls and energy 
 3-43

isolating devices apply to a particular machine or piece of equipment is 

acceptable. 

To assist employers and employees in complying with the procedural requirements, 

OSHA developed a non-mandatory Typical Minimal Lockout Procedure guideline in 

Appendix A of the standard. The compliance assistance tool provides employers with 

guidelines for a simple energy control procedure for use in both lockout and/or tagout 

applications. This flexible template may be used when there are limited numbers or types 

of machines or where there is a single power source. The user would simply need to fill 

in the blanks with the machine-specific data – pursuant to §1910.147(c)(4). 

NOTE: Nothing in the appendix adds to or detracts from any of the requirements of 

the standard. 

For more complex systems, a more comprehensive procedure(s) will need to be 

developed, documented, and utilized. The appendix may be used as a guide to develop a 

more complex control procedure, and the sample lockout procedure can be applied to 

many different workplace situations with minor adaptations or changes. 

NOTE: OSHA issued a citation to an employer alleging a serious violation of the 

LOTO standard stating that the employer did not develop energy control 

procedures meeting the §1910.147(c)(4)(ii) requirements. The employer's 

procedure, according to the Occupational Safety and Health Review 

Commission, appeared to be derived from Appendix A to §1910.147; 

however, company officials failed to fill in any of the blanks in the Appendix 

A procedure. The decision explains that in order for this form to be effective, 

the employer must provide specific, relevant information, including the: 

1. Names of affected employees; 

2. Types and magnitude of energy; 

3. Hazards; 

4. Methods to control the energy; 

5. Types and locations of machine or equipment operating controls; 

6. Types and locations of energy isolating devices; 

7. Types of stored energy and methods to dissipate or strain energy; and 

8. Method of verifying isolation of the equipment. 

The Commission held that the employer’s general procedure was unacceptable 

because it fell far short of the standard's requirements and provided no 

information about the employer's individual machines that would enable an 

employee to lock out a machine safely. The purpose of the energy control 

procedure is to guide an employee through the lockout process. Thus, the 

Commission affirmed the violation of §1910.147(c)(4)(ii). See Drexel 

Chemical Co. (OSHRC Docket No. 94-1460, 1997) for additional information 

on the decision. The Commission reaffirmed this position in General Motors 

Corp., CPCG Oklahoma City Plant, (Docket Nos. 91-2834E and 91-2950, 
 3-44

2007). 

Although the standard requires the procedure to be written in detail, this does not mean 

that a separate procedure must be written for each and every machine or piece of 

equipment. Similar machines and/or equipment (such as those using the same type and 

magnitude of energy), which have the same or similar types of controls, and which can be 

rendered safe using the same sequential procedural steps, can be covered by a single 

procedure, if that procedure satisfactorily addresses the hazards and specifies the 

measures for controlling the hazards. For purposes of procedure grouping, machines and 

equipment may be grouped together as one procedure if they all are listed or identified in 

the scope of the energy control procedure and if they all have the same or similar: 

A. Procedural steps for shutting down, isolating, blocking, securing, and dissipating 

stored energy in machines or equipment; 

B. Procedural steps for the placement, removal, and transfer of the lockout or tagout 

devices and the responsibility for them; and 

C. Requirements for testing a machine or equipment to determine and verify the 

effectiveness of LOTO devices and other control measures. 

Thus, for example, an employer who has a number of power presses with similar design 

characteristics and energy sources, may decide to group their die-setting activities into a 

single procedure if the presses have the same or similar control measures and the same 

sequential procedural steps are used for controlling hazardous energy. However, this 

single procedure would need sufficient detail and clarity to guide a die-setter safely 

through the task steps when servicing each of the power presses. Alternatively, 

employers may choose to develop separate die-set procedures for each press or each type 

of press. Either method is acceptable as long as the energy control procedure detail 

provides authorized employees enough information and guidance to safely accomplish all 

die set-up tasks – e.g., when, where, how and in what order to: 1) position the slide, 2) 

open the electric disconnect switch, 3) install the safety blocks, and 4) insert the die 

shoes. 

Likewise, many of the machines (e.g. table saws, radial arm saws, planers, routers, 

grinders, conveyors) in a woodworking shop are similar for purposes of the energy 

control procedure requirements because they all use relatively the same or similar types 

(e.g., 120 VAC and 240 VAC, nominal electric disconnect switches) of energy, have the 

same or similar controls for isolating the machines from the energy source, and use the 

same sequential procedural steps to protect employees from the mechanical hazards (e.g., 

shut off the machine; open the electric disconnect adjacent to the machine; apply a 

personal LO device; allow the blades or other machine components to stop before 

removing the guards; verify that the machine is isolated and can not unexpectedly startup). Therefore, a single energy control procedure may be used for this group of 

woodworking machines, as long as the procedure includes each machine within its scope 

and has sufficient specificity to allow employees to effectively isolate the hazardous 

energy source(s) and safely return each of the machine(s) to service. 
 3-45

NOTE: OSHA recognizes that some employers choose to develop "machine-specific" 

energy control procedures for individual machines or pieces of equipment 

because this approach provides an optimum level of detail, enhancing overall 

employee safety during servicing operations. In order not to discourage this 

practice, employers who develop energy control procedures for individual 

machines still may group same or similar individual machine/equipment 

procedures for periodic inspection purposes. [See Section XVII of this 

chapter for details.] 

However, OSHA recognizes that, while in many cases an employer will be able to 

develop a single energy control procedure applicable to all machines and equipment in a 

facility, an employer may be required to develop more than one procedure when 

variations in machine types, energy sources, or energy control methods mandate 

additional specificity in order to permit employees to effectively isolate hazardous energy 

and safely perform servicing/maintenance activities. 

For example, a single procedure for a number of machines would not be adequate if it 

does not guide an employee through the energy control process and provide the specific 

instruction necessary to permit the employee to protect herself effectively from hazardous 

energy associated with each piece of machinery. For example, assume that a single 

procedure is intended to cover a group of machines and that part of the energy control 

procedure requires the use of a start/stop button for shutdown and energy isolation 

verification purposes. However, one of the machines does not have a start/stop button 

because it is wired directly to an electronic on-demand signal. In this scenario, the single 

procedure will not provide adequate instructions for the machine without a start/stop 

button because the single procedure will not provide sufficient employee guidance on 

how to effectively shut down the machine and verify energy isolation. 

Likewise, grouping dissimilar process systems (e.g., an ammonia refrigeration vs. a 

natural gas fuel heating system) with different types of hazards and control step sequences 

or unique control measures within a single energy control procedure would not be 

permitted if the procedure did not sufficiently specify the hazards and specific control 

measures pursuant to the LOTO standard's energy control procedure provisions. The 

Agency recognizes that, while in many cases an employer will be able to develop a single 

energy control procedure applicable to all machines and equipment in a facility, the 

employer is required to develop more than one procedure (or to supplement a single, 

generic procedure with supplemental means such as checklists, appendices, or work 

authorization permits) for unique or different energy sources, particularly when the 

associated control measures are dissimilar. 

It is important to emphasize that the nature of the machine or piece of equipment (i.e., its 

production function) is not a significant factor in deciding whether machines/equipment 

can be covered by a single procedure. For example, machines that are designed to 

perform different production functions (e.g., a mechanical conveyor, an electrically 

powered ironworker, a table saw, and a multi-spindle milling machine) may be covered 

by a single procedure if the procedure clearly and specifically details the same or similar 
 3-46

energy control (LOTO) measures such that the authorized employees have sufficient 

guidance to enable them to safely and effectively utilize hazardous energy control 

measures for each of the machines that will be included within the procedure. 

OSHA recognizes that many portions of an energy control procedure may be standardized 

for an entire facility. However, it is necessary to supplement the generic procedure with 

checklists or other supplemental means (e.g., a checklist, work authorization permit 

system, or manufacturers' servicing and maintenance guidelines) to provide the required 

specificity – pursuant to paragraph (c)(4)(ii) – when variations (e.g., differences in the 

machines/equipment, types of energy, energy isolation devices, or hazards) necessitate 

additional specificity to enable employees to safely and effectively control hazardous 

energy when working with particular machines or equipment. The generic procedure and 

supplemental means must provide authorized employees with clear and detailed guidance 

so that they can understand how to safely and effectively utilize hazardous energy control 

measures for the machine or equipment being serviced or maintained. 

For example, if not apparent, the checklist might address the number and locations of the 

energy isolating devices in order to achieve total de-energization. If the procedure itself 

takes the form of a checklist, it must reflect, in part, the sequence of steps necessary to 

safely and effectively control all hazardous energy sources. The information contained in 

the generic procedure and supplemental means would, at a minimum, need to meet the 

performance-oriented requirements of the LOTO standard. 

NOTE: The use of generic energy control procedures alone are unacceptable, if

generic procedures do not meet the provisions set forth in §1910.147(c)(4)(ii). 

In the chemical process and petroleum refining industries, for example, companies 

augment generic LOTO procedures with work authorization permit systems to detail the 

job-specific hazardous energy control measures before employees perform servicing and 

maintenance work activities. It is recognized that the comprehensive use of such a 

system is more efficient and relevant to the daily tasks than would a cookbook type 

procedure, which might not fully account for a specific situation that might have occurred 

around the time of the servicing and maintenance activity. 

However, if a company uses a work permit authorization system, each permit must 

identify the: 1) equipment to be serviced/maintained, 2) types and unique energy 

characteristics that may be encountered, and 3) specific safe work procedures to be used 

to effectively control hazardous energy associated with the permit's scope of work. 

Ultimately, however, the quality of any hazardous energy control effort, and ultimately 

employee safety, is dependent upon the hazard analysis, which in turn is dependent upon 

the knowledge and skill of the individuals – e.g., operations personnel, engineering 

support – that identify the tasks, the energy related hazards, and appropriate control 

measures for the specific servicing operation. 

NOTE: Work authorization permit system procedures must, in part, specify that 

employees are required to perform their work in accordance with the terms 
 3-47

and limitations of the work permit and include the means to enforce employee 

compliance with the work permit provisions. Chapter 4, Section VI of this 

manual also contains information on the use of work authorization permits as 

employee accountability devices in group LOTO (control and accountability) 

procedures. 

With the understanding that the standard is flexible and performance-oriented, many 

procedural items may be incorporated into a generic plant-wide policy (when 

supplemental means are used) or incorporated without revision into each energy control 

procedure, regardless of the type of machine or equipment, the type of energy, or the 

energy control devices associated with the control of the hazardous energy. For example, 

an employer may decide that it is better to address the purpose and use of the procedure, 

as well as other general issues, in their generic procedure's policy sections. The following 

are some general policy issues that may be capable of being developed and contained in 

the generic portion of the company's energy control procedure: 

A. Who is authorized to perform LOTO? 

B. Who will notify affected employees of the application and removal of LOTO 

devices? 

C. What method (e.g., lockout versus tagout, including, where appropriate, full 

employee protection measures) will be used for securing energy isolating devices? 

D. What types of energy isolation (e.g., electric disconnects) and control methods 

will be employed in the facility? 

E. How will energy control devices be removed and by whom? 

F. If removal by others is contemplated by the employer in situations permitted 

under the LOTO standard, what are the specific procedural steps for the removal 

of the authorized employee's LOTO device by someone other than the person who 

applied the device? 

G. How will the removal of control devices and re-energization be performed? 

H. How will the implementation of these energy control procedures be supervised 

and enforced? 

I. Where groups perform servicing or maintenance work, how will the group LOTO 

activities be performed and coordinated? 

J. Where the servicing or maintenance exceeds a single shift or there is a personnel 

change, how will authorized employee responsibility be transferred during shift 

and personnel changes (e.g., job locks)? 

K. Where contractor employees may be affected by hazardous energy, how will 

outside personnel (e.g., contractors) be informed of energy control procedures? 

Some issues that an employer may need to incorporate in its supplemental sections, such 

as a checklist, include: 

A. What equipment is being serviced/maintained and what is the scope of work? 

B. What are the specific (types and magnitude) hazardous energy sources associated 

with the system and the specific method and sequence of activities required to 

control these hazards? 
 3-48

C. How is a safe and orderly shutdown of the system performed? 

D. Where (if not readily apparent) and how does the isolation or blocking of energy 

occur? 

E. How is stored energy in the system released? 

F. Are there precautions (e.g., use of a test instrument) necessary to monitor for 

hazards associated with energy re-accumulation? 

G. How do authorized employees test and verify that de-energization and isolation 

have been accomplished? 

H. How are LOTO devices removed and what are the steps to re-energize the 

system? 

I. How do employees safely test and position machine components? 

In summary, when CSHOs evaluate an employer's energy control procedures, they must 

determine: 

Whether an energy control procedure, pursuant to §1910.147(c)(4)(ii), provides 

sufficient detail and adequate guidance for an authorized employee(s) to clearly 

understand how to safely and effectively utilize hazardous energy control 

measures for the particular machine or piece of equipment being serviced and/or 

maintained?

If the procedure does, the employer has complied with this performance-oriented 

standard. 

X. Application of Control Measures. The implementation of energy control procedures is 

accomplished, in large part, by following the provisions of paragraph 1910.147(d). The 

established procedure contains six separate and distinct steps which must be followed in 

the order that they are presented [(d)(1) through (d)(6)]. The following energy control 

elements and actions are presented in the sequence in which they must be implemented, 

and several fatality case reports, from the NIOSH Fatality Assessment and Control 

Evaluation (FACE) Program, are presented for illustrative purposes: 

A. Preparation for shutdown, which requires each authorized employee to have 

knowledge of the type and magnitude of the energy, the hazards of the energy to 

be controlled, and the means for controlling these hazards; 

B. Machine or equipment shut down in accordance with established procedures 

required by this standard. An orderly shutdown must be utilized to avoid any 

additional or increased hazards as a result of de-energization; 

FACE Report No. 94CO02901: Recycle Technician Died from Injuries 

Sustained When He Fell into a Cardboard Compactor – Colorado 

[http://www.cdc.gov/niosh/face/ stateface/co/94co029.html]. A 38-yearold worker at a county sanitary landfill died after falling into a large trash 

compactor used to bale cardboard for recycling. The cardboard was lifted 

20 feet by a belt conveyor and fed through a 20- by 44-inch opening into a 

hopper. The hopper had automatic controls that activated the baler when 
 3-49

enough material collected in the baling chamber. When the baler was 

activated, material in the chamber was compressed by a ram that entered 

the chamber from the side. Excess material above the chamber was 

trimmed by a shearer. 

On the day of the incident, cardboard jammed at the conveyor discharge 

opening. Without stopping, de-energizing, or locking out the equipment, 

the victim rode the conveyor up to the discharge opening to clear the jam. 

He fell into the hopper and the baling cycle was automatically activated, 

amputating his legs. The victim bled to death before he could be removed 

from the machine [Colorado Department of Public Health and 

Environment 1994]. 

C. Operation of all energy isolating devices that are needed to control the hazardous 

energy to the machine or equipment; 

FACE Report No. 5: Uncontrolled Kinetic and Thermal Energy (NIOSH 

ALERT No. 99-110). A 33-year-old janitorial worker died after he was 

trapped inside a linen dryer at a hospital laundry while cleaning plastic 

debris from the inside of the dryer drum. The cleaning task (which usually 

took 15 minutes to an hour) involved propping open the door to the dryer 

with a piece of wood and entering the 4- by 8-foot dryer drum. The melted 

debris was removed by scraping and chiseling it with screwdrivers and 

chisels. The dryer was part of an automated system that delivered wet 

laundry from the washer through an overhead conveyor to the dryer, where 

it was dried during a 6-minute cycle with air temperatures of 217°

 to 

230°

F. The system control panel was equipped with an error light that was 

activated if the dryer door was open, indicating that the dryer was out of 

service. 

On the night of the incident, the victim propped the door open and entered 

the dryer drum without de-energizing or locking out the dryer. He began 

to clean the inside of the drum. Although the error light had been activated 

when the door was propped open, the signal was misinterpreted by a 

coworker, who restarted the system. When the system was restarted, the 

overhead conveyor delivered a 200-pound load of wet laundry to the 

dryer—knocking out the wooden door prop, trapping the victim inside, 

and automatically starting the drying cycle. The victim remained trapped 

inside until the cycle was completed and was discovered when the load 

was discharged from the dryer. He died thirty minutes later of severe 

burns and blunt head trauma [Massachusetts Department of Public Health 

1992]. 

D. Application of lockout or tagout devices to the energy isolating devices by 

authorized employees so that they hold the isolation devices in a “safe” or “off” 

position; 
 3-50

FACE Report No. 95-12: Laborer Fatally Injured While Cleaning 

Concrete Mixer – Tennessee [http://www.cdc.gov/niosh/face/Inhouse/full9512.html]. A 25-year-old male worker at a concrete pipe 

manufacturing facility died from injuries he received while cleaning a 

ribbon-type concrete mixer. The victim's daily tasks included cleaning out 

the concrete mixer at the end of the shift. The clean-out procedure was to 

shut off the power at the breaker panel (approximately 35 feet from the 

mixer), push the toggle switch by the mixer to make sure that the power 

was off, and then enter the mixer to clean it. 

No one witnessed the event, but investigators concluded that the mixer 

operator had shut off the main breaker [without applying a LOTO device] 

and then made a telephone call instead of following the normal procedure 

for checking [verification of energy isolation] the mixer before anyone 

entered it. The victim did not know that the operator had de-energized the 

mixer at the breaker. Thinking he was turning the mixer off, he activated 

the breaker switch and energized the mixer. The victim then entered the 

mixer and began cleaning without first pushing the toggle switch to make 

sure that the equipment was de-energized. The mixer operator returned 

from making his telephone call and pushed the toggle switch to check that 

the mixer was de-energized. The mixer started, and the operator heard the 

victim scream. He went immediately to the main breaker panel and shut 

off the mixer. 

Within 30 minutes, the emergency medical service (EMS) transported the 

victim to a local hospital and then to a local trauma center. He died 

approximately 4 hours later [NIOSH 1995]. 

E. Relieve, disconnect, restrain, or otherwise render safe all potentially hazardous 

stored or residual energy in the machine or equipment. If re-accumulation of 

hazardous energy is a possibility, then the verification of isolation must be 

continued until the servicing/maintenance is completed, or until the possibility of 

such accumulation no longer exists; and 

Steel Manufacturing Incident – Gas Condensate Fire; Investigation 

Report, No. 2001-02-I-IN; Chesterton, IN, February 2, 2001; U.S. 

Chemical Safety and Hazard Investigation Board. On February 2, 2001, 

workers were attempting to remove a slip blind and a cracked valve from a 

coke oven gas line leading to a decommissioned furnace in preparation for 

a cutting and welding operation. In this incident, workers first purged the 

piping system with nitrogen to force out residual chemicals, including a 

hazardous mixture of peroxide and alcohol that reacts violently when 

heated. But unknown to the workers, the piping system included a 300-

foot-long section that was three feet lower than the rest of the pipes, and 

despite the nitrogen purge, a significant amount of the hazardous mixture 

remained trapped. 

The next step in the operation was to use high-temperature steam to purge 
 3-51

the piping of what workers believed would be a small amount of residual 

flammable hydrocarbon vapor. But the steam heated the peroxide that was 

trapped in the low section of piping. The peroxide then began to 

decompose, releasing heat and creating intense pressure. The pressure 

blew out a valve gasket and violently ruptured the pipe. Flammable 

vapors shot out of the openings and ignited into a large fireball, injuring 

plant workers. One millwright and one contractor supervisor died. Four 

millwrights were injured, one seriously. 

After the accident, two drains were found in the low section of the pipe, 

which could have been used to remove the trapped liquid [residual 

hazardous energy]. According to the CSB, had the procedures called for 

reviewing plant pipe drawings and physically walking the entire line 

within the work boundaries, the accident [involving residual flammable 

chemical energy] likely would have been avoided. 

F. Verification by the authorized employee that the previous steps of the procedure 

have effectively isolated the machine or equipment. This must be done prior to 

starting the servicing or maintenance work. The authorized employees need to 

verify that: the machine or equipment has been turned off or shutdown properly as 

required by paragraph (d)(2) of the standard; all the energy isolating devices were 

identified, located and operated as required by paragraph (d)(3); the LOTO 

devices have been attached to the energy isolating devices as required by 

paragraph (d)(4); and the stored energy has been rendered safe as required by 

paragraph (d)(5). The authorized employees also need to verify that, by 

performing these steps, they have effectively isolated hazardous energy associated 

with their servicing and/or maintenance activities such that they cannot be injured 

by hazardous energy sources while performing the servicing and/or maintenance 

activities. These potentially life-saving steps are intended to ensure the employee 

that the machine or equipment is isolated from the energy source, that the residual 

energy has been dissipated or blocked, and that injury could not result from the 

inadvertent activation of the operating controls. 

Both visual inspections and physical tests are important elements of verification 

of de-energization. The use of visual inspection techniques is critically important 

as authorized employees can visually confirm that switches, valves, breakers, etc. 

have been properly moved to and secured in the off or safe position. Visual 

inspection can also verify whether or not LOTO and other protective devices have 

been applied to the control points in a manner that would prevent the unsafe 

movement of the switches or valves. Finally, a visual inspection can be used to 

verify that isolation has taken place by determining that all motion has stopped 

and that all coasting parts such as flywheels, grinding wheels, saw blades, etc. 

have come to rest. 

However, in the majority of situations, visual inspection techniques must be 

accompanied by physical tests to ensure that the steps taken to isolate hazardous 

energy have worked successfully to isolate the energy from the machine or piece 
 3-52

of equipment. OSHA emphasizes that, in order to reliably ascertain whether 

hazardous energy has been effectively isolated; the authorized employee generally 

will need to use a combination of visual inspection techniques and other detection 

methods. Depending upon the measures necessary to detect the presence of 

hazardous energy, visual inspection techniques generally will need to be 

performed in conjunction with the use of a test instrument (e.g., voltmeter; 

combustible gas indicator) and/or a deliberate attempt to start-up machines or 

equipment. Indeed, in most cases, it is only through the use of a test instrument or 

a deliberate attempt to start-up a machine that the authorized employee will be 

able to ascertain whether the steps taken to isolate hazardous energy (which were 

checked through visual inspection techniques) actually worked to isolate the 

energy from the machine. The appropriate combination of verification methods 

will depend upon the types of machinery or equipment involved, the complexity 

of the system, and other factors. 

For example, visual verification that a disconnect switch is in the open or off

position, even in conjunction with the operation of the equipment’s control(s), is 

not a reliable indication that an electric circuit has been de-energized when 

employees will be working on or near exposed electrical parts. It is possible to 

interrupt a portion of the circuit so that the equipment will not operate even 

though the rest of the circuit is still alive. Therefore, a qualified person must use 

test equipment to verify de-energization by testing the electric circuit elements 

and equipment parts to which employees will be exposed. A test is also required 

to check for any voltage even though specific parts of a circuit have been deenergized and presumed safe because it is possible, under certain conditions, to 

feed circuits from the load side (e.g., back-feed; short circuit) or to have induced 

voltage. See §1910.333(b)(2)(iv) on electrical safety-related work practices for 

further details. 

Commission Decision: In a split decision in Interstate Brands Corp., 20 BNA 

OSHC 1102 (Docket No. 00-1077, 2003), the Occupational Safety and Health 

Review Commission (OSHRC) vacated a citation item charging the employer 

with failing to include a procedure for verifying the effectiveness of energy 

control procedures for a particular piece of equipment in the energy control 

program. The program generally required that, after locking or tagging out 

equipment, employees were both to check the equipment visually and to attempt 

to restart it to verify that it was de-energized. The equipment at issue did not have 

an on/off switch, and the program did not provide an alternative verification 

method. The Commission held that the Secretary had not established that the 

visual verification method by itself was inadequate in the particular circumstances 

of the case. 

Inspection Strategy: In most workplaces where the LOTO standard applies, 

enforcement will not be affected by the IBC decision because the decision applies 

to the specific facts at issue. 

In situations where an energy control procedure provides only visual verification 
 3-53

of isolation, CSHOs should determine whether the visual verification alone would 

be effective, and if not, must sufficiently document why the visual verification 

steps alone are inadequate to ensure the effective isolation of hazardous energy. 

Proposed citations based on the inadequacy of visual verification techniques alone 

should be discussed with the OSHA Regional Office and the Solicitor's Office.

XI. Removal of Lockout/Tagout Devices. Paragraph 1910.147(e) requires that certain actions 

be taken before LOTO devices are removed from energy isolating devices so that 

equipment may be returned to a safe operating condition without injury to employees. 

Due to the performance-oriented nature of the provisions, they are expressed in broad 

terms. As such, the employer is responsible for, and is in the best position to make a 

determination of the hazards associated with the system energization or startup and the 

appropriate control measures, because the employer is familiar with its operation of the 

equipment and relevant energy hazards. 

Pursuant to §1910.147(e), all of the following steps must be accomplished by authorized 

employees in accordance with the specific provisions of the employer’s energy control 

procedure before LOTO devices are removed and energy is restored to the machine or 

equipment. 

A. Inspect machine/equipment system components to ensure that: 1) non-essential 

tools and materials have been removed; and 2) machine or equipment components 

are operationally intact. Any inoperable safeguard or extraneous item in the 

maintenance area, for example, can potentially cause injury to employees if the 

equipment were to be re-energized or started up. 

These §1910.147(e)(1) pre-startup inspection steps are intended to ensure that the 

machine or equipment has been returned to an effective operating condition, so 

that it is safe to re-energize the machine/equipment after the servicing or 

maintenance is complete. Depending on the equipment design, visual inspection 

alone might be sufficient to meet this requirement. For example, a verification 

procedure may be as simple as having a foreman, supervisor or other person-incharge ask the employees if they are done, and then spot check the equipment to 

ensure that it is safe to be returned to normal operations. Such spot checking 

could include a simple determination of whether the machine guards are 

functioning (as intended) and whether employees have cleaned up after 

themselves. A more complicated machine or equipment system, however, may 

require additional measures, which may include, but are not limited to, checking 

equipment manufacturer design specifications or following pre-start-up 

procedures and checklists. 

B. Check the location of all employees, and ensure that all employees have been 

removed from machine/equipment areas and are positioned safely. This 

determination usually can be accomplished by a visual inspection; however, 

depending on the size and/or complexity of the equipment and the scope of the 

operation, the determination may necessitate the use of administrative procedures 
 3-54

and warning devices such as horns, bells or buzzers. [§1910.147(e)(2)]. 

C. Each LOTO device must be removed by the employee who applied the device. 

This is an essential step in the procedure because each authorized employee will 

have her own personal LOTO device attached to the energy isolating device(s) 

during maintenance operations. [§1910.147(e)(3)]. The employer must have 

procedures in place to determine whether all such devices have been removed by 

each authorized employee before re-energization or startup. 

D. Inform affected employees (as defined by 1910.147(b)) that the lockout or tagout 

device(s) have been removed and that the machine or equipment will be reenergized. [§§ 1910.147(c)(9) and (e)(2)(ii)]. It is at this point when the control of 

the equipment is typically transferred back to the operations personnel for the 

purpose of returning the system to normal production operations – i.e., as the 

authorized employee(s) relinquish their personal control over the hazardous 

energy source(s). 

NOTE: A start-up (re-energizing) procedure is considered a normal production 

operation and is not normally covered by the provisions of §1910.147 

as long as the procedure does not involve: 

• Testing or positioning of machines, equipment or components 

thereof (as detailed in 1910.147(f)(1)); or 

• Setting up (as defined in 1910.147(b)). 

For example, a machine startup may simply involve placing the 

electric disconnect in the on position and pushing a control switch to 

start the production operation. In this scenario, the LOTO standard 

would not apply as the operator is utilizing the machine to perform its 

normal production function. However, in other instances, servicing 

and/or maintenance activity, and subsequent coverage by §1910.147, 

may occur following the re-energization of the machine or equipment. 

For example, if an employer must test or position equipment to 

determine if the servicing and maintenance activity was successful, or 

to complete the setting up of equipment, this would still be considered 

servicing and maintenance activity as defined by the standard. Under 

these situations, the provisions of §1910.147 will continue to apply 

until the machine or equipment is capable of performing its intended 

production function. 

E. Safely start-up (re-energize) the equipment in accordance with generally 

recognized good engineering practice. An orderly start-up procedure must be 

utilized to avoid any additional or increased hazards to employees as a result of 
 3-55

machine or equipment start-up. 

NOTE: The employer is still obligated under the Occupational Safety and 

Health Act of 1970 to take reasonable steps to protect employees from 

the recognized hazards associated with the operation. In other words, 

the machine or equipment must be re-energized and/or started up in 

such a manner to avoid any additional or increased hazard(s) to 

employees as a result of the re-energization or startup process. Failure 

to do so may constitute a violation of a specific OSHA standard (e.g., 

the 29 CFR §1910, Subpart O Machinery and machine guarding

standards; the Process safety management standard, §1910.119) or the 

General Duty Clause, Section 5(a)(1) of the Act, if an employer has 

failed to furnish a workplace that is free from recognized hazards 

causing or likely to cause death or serious physical hazard. See 

§1910.5(f). 

With regard to LOTO device removal (Step C), it cannot be over-emphasized that 

employees who work on de-energized machinery may be seriously injured or killed if 

LOTO devices are removed and the machinery is re-energized without their authorization. 

 Lockout or tagout is personal protection. For this reason, it is extremely important that 

all employees respect lockout and tagout devices and that the LOTO devices be removed 

only by the person(s) who applied them. In the rare situation in which the employee who 

placed the LOTO device is not available to remove that LOTO device, the device may be 

removed under the direction of the employer, provided that the employer’s energy control 

program incorporates specific procedures and training for that purpose. 

NOTE: Pursuant to the paragraph (e) exception, these procedures must incorporate, at 

a minimum, measures to accomplish the following: 

• Verification that the authorized employee (who applied the device) is not 

at the facility; 

• Making all reasonable efforts to contact that employee to inform him or 

her that the LOTO devices(s) has been removed; and 

• Ensuring that this employee knows of the removal of the device before he 

resumes work at the facility. 

Removal of a personal LOTO device by another person may not be based on convenience 

and may not be done simply because the employee is not available at the LOTO location, 

but is still at the workplace. The steps above are necessary to ensure that the employee 

who is protected by the device is not exposed to energy hazards either at the time of its 

removal or after its removal. 

XII. Machine or Equipment Testing or Repositioning. The LOTO standard requires an 

employer to develop and utilize a procedure, in conjunction with the energy control 

procedure that establishes a logical sequence of actions to be taken in situations where 

energy isolating devices are locked and/or tagged out and there is a need for machine 
 3-56

component testing or positioning. OSHA allows temporary removal of LOTO devices 

and the re-energization of the machine only when necessary to perform particular tasks 

that require energization – i.e., when power must be restored to test or position machines, 

equipment, or their components. However, employers must provide employee protection 

(e.g., via machine guarding techniques when it is not possible to remove an employee(s) 

from the danger area) that eliminates exposure to hazardous energy during all phases of 

the testing or repositioning operation. 

NOTE: Area Directors shall cite the §1910.147(f)(1) sequence of step requirements, 

and not the paragraph (c)(4) provisions, when an employer fails to develop or 

utilize procedures to safely test or position machines/equipment in conjunction 

with servicing and maintenance activities. 

When testing or positioning is necessary, the relevant procedure must establish a 

sequence of actions to be undertaken, in accordance with §1910.147(f)(1), since 

employees may be exposed to significant risks during these transition periods. These 

actions are required to maintain the integrity and continuity of employee protection. 

These prescribed steps must be implemented in sequence prior to re-energization: 

A. Clear machines of tools and materials – See §1910.147(e)(1); 

B. Remove employees from the hazardous areas around the machine – See 

§1910.147(e)(2); 

C. Remove the lockout or tagout devices as specified in the standard – See 

§1910.147(e)(3); 

D. Energize the machine and employ effective employee protection while testing or 

positioning machinery; and 

E. Turn off all systems, isolate the machine from the energy source, and reapply 

lockout or tagout devices as specified, if additional servicing or maintenance is 

required – See §1910.147(d). 

This temporary exception applies only for the limited time required for testing or 

repositioning the machine/equipment or its components. When an energized state is no 

longer required, the authorized employees must again de-energize the machine/equipment 

and resume the energy control measures. Paragraph (f)(1) of the standard does not allow 

the employer to disregard the requirement for locking out or tagging out during other 

portions of the servicing or maintenance operation. 

XIII. Outside Personnel. Outside servicing and maintenance personnel, such as contractors, 

service representatives, or employees from a temporary employment agency engaged in 

general industry activities are subject to the requirements of this standard. These 

requirements are necessary when outside personnel work on machines or equipment 

because their activities have the same or greater potential for exposing employees to 

servicing or maintenance hazards as would exist if the on-site employer’s own employees 

were performing the work. 
 3-57

If outside contractors service or maintain machinery, the on-site employer and the 

contractor must inform each other of their respective lockout or tagout procedures. The 

performance-oriented nature of the standard permits the outside (contractor) employer to 

use either: the host employer's energy control procedure, which some companies will 

require; its own procedures; or a combination of the two procedures, provided the 

resulting procedure meets the requirements of the LOTO standard. In some instances, for 

example, the host employer will prohibit the contractor from shutting down and isolating 

the host's equipment and the host will implement many of the equipment-specific energy 

control measures contained in the LOTO standard's energy control procedural 

requirements. See §1910.147 (c)(4)(ii). The contractor employees would then apply their 

own personal LOTO devices to a group LOTO mechanism, such as a lockbox, before 

they verify that the energy sources have been adequately isolated and de-energized. In 

summary, each employer has an employee protection obligation to control hazardous 

energy, and this performance oriented standard allows the employers the flexibility on 

how to meet the LOTO standard requirements. 

NOTE: Refer to the Citation Guidance policy contained in Chapter 2, Section III.A for 

additional information regarding host employer and outside contractors and 

OSHA's Multi-Employer Citation Policy, CPL 02-00-124. 

On-site employers and outside employers must inform each other of their respective 

LOTO procedures. OSHA expects that, in most cases, the on-site and outside contractors 

will exchange copies of their respective energy control procedures and may, when 

appropriate, have a discussion regarding relevant provisions (e.g., control measures for all 

hazardous energy sources potentially to be encountered) of the respective procedures. 

This provision is intended to ensure that both the host employer and outside personnel are 

aware that their interaction can be a possible source of injury to employees and are 

effectively coordinating energy control procedure interaction to protect all employees 

from hazardous energy. [See paragraph 1910.147(f)(2)(i).] 

The onsite employer and the contractor also must each ensure that its respective 

employees understand and comply with all requirements of the contractor’s energy 

control procedure(s). [See paragraph 1910.147(f)(2)(ii).] The facility owner must 

evaluate the various aspects of the contractor’s energy control procedure(s) to ensure that 

its own employees are not placed at risk by the implementation of the contractor's 

procedure because each employer has an independent obligation under the OSH Act to 

provide employee protection. This knowledge prevents any misunderstanding by either 

the plant employees or the outside personnel regarding the application of the energy 

control procedures. 

XIV. Group Lockout/Tagout. Group LOTO applies to the performance of servicing or 

maintenance activities when more than one employee is engaged in the servicing 

operation. When servicing and maintenance is performed by a crew, craft, department or 

other group, a procedure must be utilized that affords each employee a level of protection 

equivalent to that provided by the implementation of a personal lockout or tagout device. 
 3-58

Regardless of the situation, the requirements of this standard specify that each employee 

performing servicing and maintenance activities must be in control of hazardous energy 

throughout her entire period of exposure. Each employee in the group needs to affix her 

personal lockout or tagout device as part of the group LOTO procedure. 

Acceptable group energy control procedures are further discussed in Chapter 4. 

XV. Shift or Personnel Changes. The employer must ensure that specific procedures are 

implemented during shift or personnel changes to provide a continuity of lockout or 

tagout protection throughout this transition period. This assurance usually involves 

action by the authorized or supervisory employee (Primary Authorized Employee) 

responsible for the coordination of affected workforces and the continuity of LOTO 

protection. See §§ 1910.147(c)(4)(ii)(C) and 1910.147(f)(4). The responsibility includes 

the orderly transfer of lockout or tagout device protection between employees on 

outgoing and incoming shifts to ensure that the machine or equipment is safe to work on. 

Generally, the transfer of responsibility can be accomplished by the oncoming shift 

accepting control of the system involved prior to the release of control over the system by 

the off-going employees. The orderly transfer of personal LOTO devices between offgoing and on-coming employees must ensure that there is no gap in coverage between the 

off-going employee's removal of her LOTO device and the on-coming employee's 

attachment of his device. 

The performance-oriented nature of this provision allows employers to utilize a variety of 

methods that ensure the continuity of LOTO protection during shift or personnel change. 

The following procedures are examples of methods that would provide such employee 

protection: 

A. All authorized employees leave their personal LOTO devices in place until the job 

is completed. The energy cannot be restored and the machine energized until all 

the employees have removed their personal LOTO devices; 

B. The on-coming employee(s) apply their personal LOTO devices before the offgoing employee(s) remove their personal LOTO devices (as many facilities have 

over-lapping shift work); 

C. Each on-coming employee starts LOTO from scratch, in accordance with 

§1910.147, by applying and releasing LOTO for the entire period of time that the 

employee services a machine. The machine is returned to operational status, with 

all the safeguards in place, so that the next employee may perform LOTO; and 

D. The use of shift or personnel transfer devices, sometimes referred to as LOTO 

continuity devices. 

For example, where the off-going employee removes his personal lockout or tagout 
 3-59

device before the oncoming employee arrives, the procedure may allow for the departing 

employee to apply another interim LOTO continuity device (Shift Transfer Device) prior 

to the time the employee removes his device. This interim procedural step would indicate 

that the departing employee’s lockout or tagout device has been removed, but that the 

machine or equipment has not been re-energized. The on-coming employees would affix 

his personal LOTO device before removing the LOTO continuity device, and each oncoming employee would then verify that the system was still isolated. 

The Job Lock, also known as the Operations Lock or Production Lock, is another 

common method used to ensure the continuity of energy isolation during multi-shift 

operations. This type of lock is the first lock placed on the energy isolating device(s) or 

lockbox, and it is the last lock removed when the job is completed. Each primary 

authorized employee from each shift controls the key to the job lock. Each authorized 

employee attaches her personal LOTO device to the group LOTO mechanism (with the 

Job Lock attached) while she performs work on the machine or equipment and removes 

the device when leaving for the day or when the job is completed. By using this Job Lock

method, the security provisions of the energy control system are maintained across shift 

changes, and this procedure provides adequate assurance to the on-coming employee that 

the machine or equipment is safe to work on. See Chapter 4, Section IV for additional 

guidance. 

In other words, LOTO continuity devices are devised for shift or personnel changes and 

they differ from personal LOTO devices because their application is intended to ensure 

the continuity of employee protection during shift and personnel changes – pursuant to 

§1910.147(f)(4). The hardware for these continuity devices must meet the prescribed 

specifications, contained in §1910.147(c)(5). However, in lieu of identifying the 

authorized employee who applied the LOTO continuity device, an employer may 

alternatively identify the party responsible (e.g., operations department; maintenance 

department) for the application and removal of the continuity device as these 

organizational groups may be responsible for the application and removal of the 

shift/personnel transfer devices. 

In addition, the requirements contained in §§ 1910.147(c)(8), 1910.147(d)(4)(i), and 

1910.147(e)(3) do not apply to LOTO devices used to ensure the continuity of employee 

protection for shift or personnel changes. In other words, the authorized employee who 

applies the continuity device (e.g., Shift Transfer Device, Job Lock) may or may not be 

the same authorized employee who removes the continuity device, as long as these 

actions are performed in accordance with the employer's established energy control 

procedure. For additional information, refer to Chapter 4, Section IV on the Job Lock 

(Type D) control measure. 

Another element for assuring continuity of protection is the requirement that each oncoming employee verify that the machine or equipment has been effectively de-energized 

and isolated. When LOTO devices (personal and/or continuity devices) remain on energy 

isolation devices from a previous shift, all of the on-coming shift employees must verify 
 3-60

for themselves the effective de-energization and isolation of the machinery or equipment. 

On-coming employees may not depend on the actions of other employees or supervisors, 

particularly those who have left the workplace for the day, for assurance that it is safe to 

work on the machinery or equipment. 

NOTE: OSHA has recognized the need for an alternative to the verification 

requirement where complex LOTO operations involve many employees and 

numerous energy isolating devices. This procedure is described in Chapter 4. 

XVI. Employee Training. OSHA's performance-oriented LOTO training program 

requirements, as detailed in §1910.147(c)(7), were developed to provide employer 

flexibility and to deal with the wide range of conditions in various workplaces. The 

specific training material will vary from workplace to workplace, and even from 

employee to employee within a single workplace, depending upon: the complexity of the 

machine or equipment and the procedures, the employee's job duties, their 

responsibilities, and other factors. 

NOTE: Self-paced, interactive computer-based training can serve as a valuable 

training tool in the context of an overall training program. However, unless 

the training program is specific to the servicing that will be performed by an 

individual employee, use of computer-based training by itself would not be 

sufficient to meet the intent of OSHA's LOTO training requirements. The 

Agency's position regarding computer-based training is essentially the same as 

our policy on the use of training videos, since the two approaches have similar 

shortcomings. OSHA urges employers to be wary of relying solely on generic, 

packaged training programs in meeting their training requirements because 

training must be relevant for the employees' actual servicing and maintenance 

work activities. Essential training information will necessarily vary from 

workplace to workplace, and even from employee to employee within a single 

workplace, depending on the type and complexity of the energy control 

procedure, as well as the employee's duties and responsibilities under the 

LOTO program. Specifically, training under LOTO includes site-specific 

elements and, very importantly, it must be tailored to employees' assigned 

duties.

 In addition, the employer has the responsibility to ensure that employees 

understand the purpose and function of the energy control program and to 

ensure that these employees have the knowledge and skills required to safely 

apply the energy control measures. In an effective training program, it is 

important that trainees have the opportunity to ask questions when material is 

unfamiliar to them. In a computer-based program, this may be achieved by 

providing a telephone hotline so that trainees will have direct access to a 

qualified trainer. Equally important is the use of hands-on training and 

exercises to provide trainees with an opportunity to become familiar with 

equipment and safe practices in a non-hazardous setting. Industrial 

operations, and in particular hazardous energy control operations, can involve 
 3-61

many complex and potentially hazardous tasks. It is imperative that 

employees be able to perform such tasks safely. 

In summary, OSHA believes that computer-based training programs and 

training videos can be used as part of an effective safety and health training 

program to satisfy OSHA training requirements, if the training as a whole 

provides employees with the information and knowledge necessary to safely 

perform the work. CSHOs can determine the adequacy of the training by 

examining the training program as a whole and by conducting employee 

interviews to evaluate employee knowledge and understanding. 

In order to provide adequate information, any LOTO training program must address, at a 

minimum, the following three areas: 1) the purpose and function of the energy control 

program; 2) the elements of energy control procedures relevant to employee duties; and 3) 

the pertinent requirements and prohibitions of the LOTO standard. The training, detailed 

in paragraph (c)(7)(i), must be specific to the needs of authorized, affected, and other 

employees, and the degree of knowledge required for these three employee groups 

diminishes from authorized employee to affected employee and from affected employee to 

other employee. 

Authorized employees are those responsible for implementing the energy control 

procedures (e.g., an employee who locks out or tags out machines) and/or performing the 

servicing or maintenance activities. These employees must have the knowledge and skills 

necessary for the safe application, use, and removal of energy isolating devices. For 

employers with a large number of procedures, each authorized employee must be able to 

safely perform the work required by any energy control procedure that he may be called 

upon to use, however rarely. Therefore, these employees need training in the applicable 

aspects of the procedure and its proper utilization, together with training in the: 

A. Recognition and understanding of all applicable hazardous energy sources; 

B. Type and magnitude of the hazardous energy sources associated with machinery or 

equipment on which they will perform servicing or maintenance; and 

C. Energy control procedures, including the methods and means to isolate and control 

relevant energy sources. 

Affected employees are those employees (e.g., machine operators and material handling 

specialists) who operate or interact with machines that are serviced and maintained 

pursuant to energy control procedures, as well as those employees (e.g., general laborers) 

who are assigned to work in areas where energy control procedures are utilized to service 

or maintain machinery. In other words, employees who are assigned to areas where 

servicing or maintenance work is performed, but who do not implement energy control 

procedures or perform servicing and/or maintenance work need only be trained as 

affected employees. Affected employees must be able to: 

A. Recognize LOTO devices immediately; 
 3-62

B. Recognize when the energy control procedure is being used; 

C. Understand the purpose and use of the procedure; and, most importantly; and 

D. Understand the importance of not tampering with lockout or tagout devices and 

not starting or using equipment that has been locked out or tagged out. 

Affected employees are required to be instructed in these matters and be informed that 

disregarding or violating the prohibitions imposed by the energy control procedure could 

endanger their own lives or the lives of their co-workers. 

All other employees who may be in an area where energy control procedures may be 

utilized must receive instruction regarding the energy control procedure and the 

prohibition against removing a lockout or tagout device and attempting to restart, 

reenergize, or operate the machinery. This instruction, which can be provided during new 

employee orientations, by use of employee handbooks, or through safety meetings, must 

convey what the energy control program does, the program’s prohibitions, and that the 

employees are not to touch any locks, tags, energy isolation devices, or equipment 

covered by this program. This instruction is required for all employees who are not 

classified as “authorized” or “affected” employees unless the company establishes, 

communicates, and enforces a policy prohibiting an employee or group of designated 

employees from ever being in an area where servicing or maintenance is performed 

pursuant to an energy control procedure. Thus, for example, this training would not be 

required for an office administrator who is prohibited from going into production areas 

where all servicing and maintenance activities are performed. On the other hand, this 

training would be required for a salesperson who rarely goes into production areas, but 

who may go into production areas to discuss product specifications associated with a 

particular order while servicing or maintenance work may be being performed. 

In addition, if tagout devices are used, all employees in all three of the aforementioned 

categories must receive training regarding the inherent limitations of tags. The training, 

described in paragraph (c)(7)(ii), must inform employees that: 

A. Tags are essentially warning labels affixed to energy isolating devices, and 

therefore do not provide the physical restraint associated with locks; 

B. Employees are not to remove tags attached to energy isolating devices by 

authorized employees (unless they are permitted to do so by the employer's energy 

control procedure due to the unavailability of authorized employees at the 

workplace – in accordance with the paragraph (e)(3) exception), and that they are 

never to bypass, ignore, or in any manner defeat the tagout system; 

C. Tags must be legible and understandable by authorized and affected employees, as 

well as other employees who work, or may work, near operations using the energy 

control procedure; 
 3-63

D. The materials used for tags, including the means of attaching them, must be able 

to withstand the environmental conditions encountered in the workplace; 

E. Tags invoke a false sense of security, and employees must understand that tags are 

only part of the over-all energy control program; and 

F. Employees must attach tags securely to energy isolating devices to prevent the 

removal of the tags during use. 

Although the standard does not prescribe annual refresher training or a set frequency for 

retraining, it does require training under specific circumstances and specifies those issues 

that the training must cover. For example, the employer must provide initial training 

before the servicing and maintenance activities begin and must provide retraining as 

necessary. However, retraining is required, by paragraph (c)(7)(iii), if a periodic 

inspection reveals, or an employer has reason to believe, that there are deviations from the 

application of the energy control procedure or inadequacies in an employee’s knowledge 

of or use the energy control procedure. Additionally, retraining must be provided for all 

authorized and affected employees whenever there is a change in: 

A. Job assignments; 

B. Energy control procedures; or 

C. Machinery, equipment, or processes that present a new hazard. 

The retraining must reestablish employee proficiency and, if relevant, address new or 

revised energy control procedures. The scope and content of all the retraining must be 

based upon the severity of the problems encountered and must be directed toward the 

elimination of those problems. Unless employees are retrained whenever deviations or 

inadequacies are discovered (or when the employer has reason to believe a problem 

exists), the overall effectiveness of the energy control program will diminish over time. 

Properly trained employees, who are proficient in their energy control responsibilities, are 

critical to the success of the energy control program. 

NOTE: OSHA issued a citation of 29 CFR 1910.147(c)(7)(iii)(A) alleging that the 

employer did not give lockout/tagout retraining to all employees who had been 

given new job assignments. The violation addressed two employees, one a 

pipe-fitter for 20 years, the other an automotive mechanic, who were 

reclassified as maintenance employees during a reorganization of the plant. 

The Occupational Safety and Health Review Commission (OSHRC) affirmed 

the citation holding that these employees were required to perform jobs they 

had not performed before and were not familiar with the associated 

lockout/tagout hazards. See Caterpillar, Inc., 17 BNA OSHC 1584, (No. 93-

2230, 1996). 

Training certifications, which contain each employee’s name and dates of training, are 
 3-64

required, by paragraph (c)(7)(iv), for both initial training and retraining. These training 

records must be kept only for the last training activity. However, the employer must 

certify that the training (required by the LOTO standard) has been given to each employee 

covered by the standard. In other words, employers must be able to demonstrate that the 

required LOTO training, which is directly relevant to the duties of the employee, was 

provided and understood. In evaluating whether an employee has been adequately 

trained, Compliance Safety and Health Officers (CSHOs) need to examine the employee's 

responsibilities under the energy control program in relation to the elements of the LOTO 

standard. 

NOTE: The American National Standard on the Control of Hazardous Energy - 

Lockout/Tagout And Alternative Methods (ANSI/ASSE Z244.1-2003; 

Communication and training, Section 5.5) utilizes an approach that, in part, 

directs users (employers) to inform all personnel regarding the provisions of 

the energy control program to an appropriate level and to apprise appropriate 

authorized individuals of aspects of the program. Very importantly, this 

consensus standard emphasizes that the user should avoid exclusive use of 

generic training programs to ensure that authorized individuals adequately 

understand the user's specific program and that a structured program should 

be used to make training understandable to all authorized individuals 

regardless of their education, primary language, or disabilities. 

The section on Communication and training, however, differs from the 

specific training requirements contained in the OSHA LOTO standard and 

utilizes a more general approach to the subject. Some of the §1910.147(c)(7) 

issues that are not explicitly addressed in the consensus standard include the 

requirement to: 

1. Train each employee in the elements of each energy control procedures 

relevant to his job duties and responsibilities (whereas Section 5.5.2 

permits employers to train personnel on a sample of machine specific 

procedures); 

2. Train employees in the pertinent requirements of the LOTO standard; 

3. Train affected employees and other employees for the subject matter 

contained respectively in §§ 1910.147 (c)(7)(i)(B) and (c)(7)(i)(C); 

4. Provide additional employee training requirements on the limitations of 

tags, as required by §1910.147(c)(7)(ii), when employees utilize tagout 

systems; and 

5. Provide retraining to re-establish employee proficiency pursuant to the 

§1910.147(c)(7)(iii)(C) requirements. 

Training, according to the LOTO requirements, must be commensurate with 

each employee's job responsibilities such that employees have the 

understanding, knowledge, and skills required to safely apply the applicable 

provisions of the energy control procedure(s). The ANSI Z244.1-2003 
 3-65

consensus standard does not affect the employer's obligation to meet all of the 

requirements contained in §§ 1910.147(c)(7) and (d)(1). 

XVII. Periodic Inspection. Due to the significant risks associated with inadequate energy 

control procedures and the failure to properly implement effective energy control 

procedures, section 1910.147(c)(6)(i) requires that periodic inspections be performed at 

least annually (based on twelve-month intervals) to verify that the procedures are 

adequate and being properly applied. OSHA believes that these periodic inspections will, 

in part, ensure that the employees involved are familiar with their responsibilities and that 

employees maintain proficiency in the energy control procedures that they implement. 

NOTE: Energy control procedures used less frequently than once a year (based on a 

twelve-month interval) need be inspected only when used. 

These periodic inspections must contain at least two components: 1) an inspection of 

each energy control procedure, and 2) a review of each employee’s responsibilities under 

the energy control procedure being inspected. Each energy control procedure required by 

§1910.147(c)(4) must be separately inspected to ensure that the energy control procedure 

is adequate and is being properly implemented by the authorized employee in accordance 

with the LOTO standard. 

NOTE: Energy control procedures that are not required to be documented, per the 

§1910.147(c)(4)(i) documentation exception, still need to be inspected and 

reviewed to ensure that they are adequate and being properly utilized. 

 

At a minimum, these inspections must include a demonstration of the procedures and 

must be performed while the authorized employees perform servicing and/or maintenance 

activities on machines or equipment. The inspections may be accomplished through 

random audits, plant safety tours, or planned visual observations. The inspector, who 

must be an authorized employee other than the one(s) utilizing the energy control 

procedure being inspected, must observe the implementation of the energy control 

procedure for the servicing and/or maintenance activities being evaluated and talk with 

employees implementing the procedure to determine that all the requirements of the 

LOTO standard are understood and being followed by employees. 

NOTE: The authorized employee performing the inspection may be someone who 

previously has or currently implements the energy control procedure being 

inspected, as long as he is not implementing any part of the energy control 

procedure while it is being inspected. In the event a small business cannot 

meet this requirement, contained in §1910.147(c)(6)(i)(A), CSHOs shall 

evaluate the situation, on a case-by-case basis, in accordance with the 

impossibility affirmative defense. See Chapter 2, Section VI.B for additional 

guidance. 

Specifically, the inspector must be able to determine whether: 1) the steps in the energy 

control procedure are being followed; 2) the employees involved know their 
 3-66

responsibilities under the procedure; and 3) the procedure is adequate to provide the 

necessary protection, and, if inadequate, what modifications are needed. 

Although not required by the standard, some employers develop, document, and utilize 

separate energy control procedures for individual machines or pieces of equipment when 

the standard would permit a single procedure to apply to the group of machines and 

equipment. An employer who exceeds the minimum requirements of the standard and 

develops distinct energy control procedures for individual pieces of machinery is not 

subjected to more extensive inspection and review obligations than an employer who 

groups a set of same or similar machines and develops a single, compliant energy control 

procedure for the set of machines. A grouping of individual procedures, meeting the 

criteria contained in this section, would be considered one procedure for periodic 

inspection purposes. 

An employer may group distinct procedures associated with similar machines or 

equipment and consider the group of distinct procedures to be a single procedure for 

purposes of conducting a periodic inspection, if the machines or equipment in the group 

have the same or similar types of control measures. Refer to Section IX of this chapter 

for additional information on energy control procedures, including the performance 

criteria for procedure grouping. 

Grouping energy control procedures for same or similar machines or equipment for 

inspection purposes may streamline the inspection and review process, since there will be 

a smaller number of procedure groups than individual procedures. Thus, an employer 

may elect to group procedures as described above, and then inspect a representative 

number of such employees implementing one procedure within each group. This 

approach is acceptable as long as the inspection sampling reasonably reflects plant 

servicing and/or maintenance operations and hazardous energy control practices for the 

procedures being inspected. 

If procedures are grouped for inspection purposes, the employer should consider selecting 

different individual procedures (from the group of same or similar procedures) each year 

for evaluation so that, over time, each individual procedure is eventually inspected as part 

of an inspection program. However, within a group of procedures, an employer may be 

justified in focusing more regularly on a subset of procedures that are more likely to be 

deficient or incorrectly implemented by employees, if institutional experience (e.g., 

accident rates associated with certain machinery) or other factors (e.g., the unusually large 

number of employees required to accomplish the servicing activity) support such a 

strategy. Regardless of the approach, these representative procedure inspections must 

reasonably reflect plant servicing and/or maintenance operations and practices. 

NOTE: If the employer chooses to group and inspect energy control procedures for 

inspection purposes, the inspector must be an authorized employee who is not 

implementing the procedure that is being inspected. If the representative 

sampling reveals an energy control procedural problem associated with one of 

the procedures that have been grouped for inspection purposes, the employer 
 3-67

must resolve the deviation or inadequacy with respect to each of the 

procedures associated with the group of machines or equipment. 

On the other hand, some companies develop an elaborate generic energy control 

procedure and supplement the generic procedure with checklists or appendices to address 

various, distinct machinery and equipment in their facilities. This type of procedure, as 

well as those described above, may be considered a single energy control procedure 

(instead of multiple procedures) for inspection purposes, if all of the criteria contained in 

this chapter on grouping same or similar machines/equipment are met. However, if 

checklists or appendices address machinery/equipment that do not all use the same or 

similar types of control measures, the employer is required to divide machinery and 

equipment referenced in the checklists or appendices into groups, such that the 

machines/equipment in any group have the same or similar types of control measures. 

Once this is accomplished, an employer may inspect and review the generic energy 

control procedure in conjunction with each distinct group of machines/equipment 

referenced in the relevant checklists or appendices. 

A review of each employee’s responsibilities under the procedure, in accordance with §§ 

1910.147(c)(6)(i)(C) and (D), is the second periodic inspection component. When 

lockout is used, the employer’s inspection must include a review of the responsibilities of 

each authorized employee implementing the procedure with that employee. When tagout 

is used, the employer must conduct this review with each affected and authorized 

employee. 

However, in order to meet the review requirement, the inspector does not have to observe 

every authorized employee implementing the energy control procedure on the machine or 

equipment on which he is authorized to do servicing and/or maintenance. Rather, the 

inspector performing the inspection may observe and talk with a representative number of 

such employees implementing the procedure in order to obtain a reasonable reflection of 

the servicing or maintenance work practices being evaluated. In addition, to supplement 

this representative inspection sampling approach, additional supplemental reviews, as 

discussed in this section, must still be performed with all of the authorized employees 

who are reasonably expected to implement the procedure during the year. Group 

meetings may be the most effective way to meet the review requirements and to reestablish employee procedure responsibilities and proficiency. 

With regard to the authorized employees (e.g., general plant maintenance personnel) who 

perform a multitude of servicing and/or maintenance tasks throughout an entire facility, it 

may not be practical for an employer to identify each of the procedures that these 

employees will implement during the year. However, before performing servicing or 

maintenance on a machine or piece of equipment, each authorized employee must have 

reviewed the inspection results from that machine or piece of equipment (or similar 

machine/piece of equipment, if machines/pieces of equipment have been grouped for 

inspection purposes). Among the acceptable methods for communicating inspection 

results to employees who were not identified previously would be to include the 

inspection review as part of an annual safety contact (if the review occurs prior to the 
 3-68

employee's implementation of the procedure at issue) or in a pre-shutdown briefing (e.g., 

as part of the Preparation for shutdown requirements contained in §1910.147(d)(1)). 

Employee retraining, if required by §1910.147(c)(7)(iii), for infrequently used energy 

control procedures must be performed prior to the start of the infrequent servicing/ 

maintenance task. 

Obviously, the content and detail of this review will be determined by the results of the 

inspection's representative sampling. For example, if the result of a representative 

procedure sampling determines that no deficiencies exist, then this review may involve 

positive re-enforcement communications through individual or group meeting(s) 

regarding the employees' procedural responsibilities. 

NOTE: Employee retraining is not required when inspections do not reveal any 

deficiencies. 

A more comprehensive review between the inspector and each authorized employee is 

necessary if it is discovered that there are deviations from the energy control procedure 

being implemented or inadequacies in employee knowledge regarding the energy control 

procedure or its application. Corrective actions (e.g., enforcement of existing procedures) 

need to be instituted and retraining must be performed whenever any inspection reveals 

inadequacies in the employee's knowledge of, or use of, the energy control procedure. 

See §§1910.147(c)(6)(i)(B) and 1910.147(c)(7)(iii)(B). 

If the inspection reveals energy control procedure inadequacies, then a more detailed 

review with all employees must be performed to address new/modified employee 

responsibilities whenever there is a change in an energy control procedure. A 

modification in the procedure necessitates additional employee retraining [in accordance 

with paragraph (c)(7)(iii)] and certification [in accordance with §1910.147(c)(7)(iv)] to 

re-establish employee proficiency for all affected and authorized employees affected by 

the change in the procedure. (Refer to Section XVI of this Chapter for policy on 

employee training.)

Additionally, employers must certify, in accordance with §1910.147(c)(6)(ii), that the 

prescribed periodic inspections have been performed. The certification must specify: 1) 

the machine or equipment on which the energy control procedure was used; 2) the date of 

the inspection; 3) the names of the employee(s) included in the inspection; and 4) the 

name(s) of the person(s) who performed the inspection. The inspection records provide 

CSHOs with a means to determine employer compliance with the standard. Most 

importantly, the inspection process provides employers with the assurance that employees 

can safely service, maintain, and repair machines and equipment. 

At one particular establishment, a work permit system (that identified the machine/ 

equipment being serviced/maintained and the authorized employees' names) had been 

developed with a section on the permit for an inspector to certify performance of all of the 

elements outlined in §1910.147(c)(6) of the standard. The inspector signed and dated the 

permit after the inspection was completed, thereby certifying, in accordance with the 
 3-69

standard, that the periodic inspection had taken place. This method would meet the 

performance-oriented requirements for the inspection component of periodic inspections, 

if the inspector was able to determine whether: 1) the steps in the procedure are being 

followed; 2) the employees involved know their responsibilities under the procedure; and 

3) the procedure is adequate to provide the necessary protection, and, if inadequate, what 

modifications are needed. This work permit inspection technique may be especially 

useful where employees perform certain LOTO tasks infrequently. 

NOTE: The American National Standard on the Control of Hazardous Energy - 

Lockout/Tagout And Alternative Methods (ANSI/ASSE Z244.1-2003; Section 

5.6) contains Program review provisions that do not mandate all of the 

minimum requirements (e.g., additional affected employee review 

requirements, pursuant to §1910.147(c)(6)(i)(D), when tagout is used for 

energy control) that are prescribed in §1910.147(c)(6) of the LOTO standard. 

The ANSI Z244.1-2003 consensus standard does not affect the employer's 

obligation to meet all of the requirements contained in the LOTO and related 

hazardous energy control standards.
 4-1

Chapter 4 GROUP LOCKOUT/TAGOUT 

This chapter provides enforcement guidelines, policy and various group LOTO procedure 

examples to assist Compliance Safety and Health Officers (CSHOs) in their evaluation of 

hazardous energy control procedures. 

NOTE: As a result of a legal settlement with the National Association of Manufacturers 

(NAM), OSHA incorporated group LOTO language into OSHA Instruction STD 1-

7.3, dated September 11, 1990. This chapter contains and references the policy that 

previously was contained in sections I.7, I.8 and Appendix C, Section B of this 

cancelled directive. 

I. Definitions. Group LOTO terms are defined in Chapter 1, Section IX of this document. 

II. Background. Group LOTO procedures described in this standard and instruction require 

each authorized employee to be in control of potentially hazardous energy hazards while 

performing servicing/maintenance work. A significant rulemaking issue involved group 

energy control procedures' level of protection and the degree of individual employee 

control over hazardous energy sources. The proposed rule for group lockout initially 

specified that an authorized employee would have a primary lock, to be affixed when the 

equipment is de-energized, and removed when the job is completed. It did not provide 

for the use of individual lockout or tagout devices by the individual employees in the 

group. Based on a re-examination of the issue, the final rule required an additional 

element that was deemed essential for the safety of employees: Each employee in the 

group needs to be able to affix her personal lockout or tagout device as part of the group 

lockout [LOTO procedure]. 

OSHA determined that this additional protection, contained in paragraph 29 CFR 

1910.147(f)(3)(ii)(D) of the final rule, was necessary for the following reasons:

A. The placement of a personal LOTO device would provide that employee with 

direct control over her own protection (until the device is removed), rather than 

having to rely completely on other people; 

B. The use of a personal device will reinforce the right of the servicing and 

maintenance employee to verify that the equipment or machinery has been 

properly de-energized and isolated in accordance with the energy control 

procedure; and 

C. The presence of the individual employee’s lockout or tagout device on an energy 

isolating device will inform all other persons, including the other authorized 

employees and supervisors, that the employee is still working on the equipment or 

machine and that it is not safe to re-energize the system. 
 4-2

 

III. Group Lockout/Tagout: Organizational Structure. Under paragraph 1910.147(f)(3)(i), 

employers are required to use a procedure that affords the employees a level of protection 

equivalent to that provided by the implementation of a personal lockout or tagout device 

when a crew, craft, department, or other group lockout or tagout device is used. The 

other elements for group LOTO, contained in paragraph 1910.147(f)(3)(ii), address 

personal lockout or tagout devices, workforce coordination and overall managerial 

procedure responsibilities. 

Although there are various ways to establish a compliant group energy control program, a 

group energy control procedure might have the following basic organizational structure. 

A. Primary Authorized Employee Designation. A primary authorized employee 

would be designated. This employee would exercise primary responsibility for 

implementation and coordination of the overall LOTO of hazardous energy 

sources for the equipment to be serviced. [§1910.147(f)(3)(ii)(C).] 

B. Primary Authorized Employee Coordination. A primary authorized employee 

would coordinate authorized employee changes and affected workforces (multiple 

work crews) with equipment operators before and after completion of servicing 

and maintenance operations that require LOTO. He also has the responsibility to 

ensure continuity of protection with respect to multi-shift energy isolation (e.g., 

through the use of group continuity devices, such as "Job Lock" or "Operations 

Lock" procedures). [§1910.147(f)(3)(ii)(C).] 

C. Principal Authorized Employee Designation. Principal authorized employee(s) 

would be designated for each workforce or crew. When more than one crew, 

craft, department, etc., is involved, one principal authorized employee would 

account for a single group of servicing/maintenance personnel. Each principal 

employee is responsible (to the primary authorized employee) for maintaining 

accountability and for the individual exposure status of each employee in that 

specific group in conformance with the company procedure. [§§ 1910.147 

(f)(3)(ii)(A) and (B).] 

D. Verification System. A verification system is implemented to ensure the 

continued isolation and de-energization of hazardous energy sources during the 

course of maintenance and servicing operations. Once the equipment is shut 

down and the hazardous energy has been controlled, maintenance/servicing 

personnel, sometimes in conjunction with operations personnel, must test the 

machinery or equipment to verify that the isolation of the equipment's energy 

source(s) is effective. The employees may walk through the affected work area to 

verify isolation. If there is a potential for the release or re-accumulation of 

hazardous energy, verification of isolation must be continued. 
 4-3

OSHA has accepted an alternative to the individual employee verification 

requirement where complex LOTO operations involve many employees and 

numerous energy isolating devices. In such situations, the employer may 

designate a primary authorized employee, with the primary responsibility for a set 

number of employees working under the group LOTO device(s). The primary 

authorized employee must implement and coordinate the LOTO of hazardous 

energy sources and verify that the steps taken, in accordance with the specific 

energy control procedure, have in fact isolated the machine or equipment 

effectively from the hazardous energy sources. This must be accomplished before 

individual authorized employees participating in the group LOTO affix their 

personal lockout or tagout device to the group LOTO box and before they perform 

servicing/maintenance activities. 

When a primary authorized employee verifies isolation, all of the authorized 

employees participating in the group LOTO must be informed of their right also to 

verify the effectiveness of the lockout measures and must be allowed to personally 

verify that hazardous energy sources have been effectively isolated, if they so 

choose. An authorized employee who opts to verify the effectiveness of the 

isolation measures must perform this verification after affixing his personal 

lockout or tagout device to the lock box and before performing 

servicing/maintenance activities. 

E. Authorized Employees. Each authorized employee must affix a personal LOTO 

device to the group lockout device, group lock-box or comparable mechanism and 

remove that device when she is finished with the servicing or maintenance activity 

[§1910.147(f)(3)(ii)(D)]. No person may attach or remove another person's 

LOTO device, including signing on or signing off for another person, unless the 

provisions of the exception to 29 CFR §1910.147(e)(3) are met. 

For example, the authorized employee in charge of a crew (“Principal Authorized 

Employee”) does not remove the group lockout or tagout mechanism from the 

energy isolating devices until each employee in the group has removed her 

personal device. Individual employee device removal indicates that employees 

are no longer exposed to the hazards from the servicing or maintenance operation. 

Most importantly, these group LOTO devices (personal lockout or tagout devices; 

group LOTO mechanisms) ensure that the equipment LOTO devices are 

maintained on energy isolating devices throughout the "life of the job." 

IV. Group Lockout/Tagout Overview. Group LOTO is required when more than one 

employee is engaged in the performance of servicing and/or maintenance activities. 

Group energy control procedures may need to be tailored to the specific industrial 

operation, but regardless of the situation, each employee performing servicing or 

maintenance activities must be in control of the associated hazardous energy throughout 

the entire period of her exposure. Absent compliance with the §1910.147(e)(3) 

exception, no employee may affix (or remove) the personal LOTO device of another 

employee. 
 4-4

The following energy control procedure overview addresses the employer's group LOTO 

requirements, and is intended to supplement other policy contained in this manual: 

A. Shutdown Preparation. Before the machine or equipment is turned off or shut 

down, each authorized employee (who is to be involved during the 

servicing/maintenance operation) must have knowledge of the type and magnitude 

of the hazards related to the energy to be controlled and of the means to control 

the energy. [§1910.147(d)(1).] In the event that the machine or equipment was 

shut down on a previous shift, the authorized employee must be made aware of 

these elements before beginning his work. 

B. Shutdown. An orderly shutdown of the machine or equipment must be conducted 

that conforms to the appropriate documented company procedure for the machine 

or equipment. The shutdown must be implemented in a manner that ensures that 

no new or increased hazards are created by the shutdown. [§1910.147(d)(2).] 

C. Affected Employee Notification. The employer or an authorized employee must 

notify affected employees prior to applying LOTO devices. Such notification 

ensures that employees do not attempt to reactivate a machine or piece of 

equipment that has been taken out of service. [§1910.147(c)(9).] 

D. Isolation. All energy isolating devices needed to control the hazardous energy to 

the machine or equipment must be physically located and operated so that they 

isolate the machine or equipment from the source(s) of energy. [§1910.147 

(d)(3).] 

E. Application of Lockout/Tagout Devices. Each authorized employee(s) must 

personally affix a lockout or tagout device to each energy isolating device (or the 

group LOTO mechanism associated with the energy isolating devices) and no 

employee may affix a personal LOTO device for another employee. [§1910.147 

(d)(4)(i).] During all group LOTO operations where the release of hazardous 

energy is possible, each authorized employee performing servicing or 

maintenance shall be protected by his personal lockout or tagout device and by the 

company procedure. 

NOTE: Paragraph 1910.147 (f)(3)(ii)(D) requires each employee in a group to 

affix his personal LOTO device as part of the group LOTO. Verbal 

accountability methods do not afford protection equivalent to that 

provided by the implementation of a personal LOTO device. The 

Occupational Safety and Health Commission (OSHRC) affirmed a 

citation on this matter by stating that this requirement clearly and 

explicitly mandates the use of a personal lockout or tagout device in a 

tagging situation because the core concept of LOTO is personal

protection. See Exelon Generating Corp., LaSalle County Station, 

OSHRC (Docket No. 00-1198, 2005). 
 4-5

1. The guidance contained in this chapter illustrates various types of compliant 

group energy control procedures. For example, a single lock on each energy 

isolating device, together with the use of a lockbox for retention of the locks’ 

keys, would permit authorized employees personal control of the hazardous 

energy source(s), if each authorized employee personally locked the lock-box. 

See the Type B group lockout illustration for further details on this technique. 

[§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. [§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. 

[§1910.147(d)(4)(iii).] 

F. Stored Energy. Following the application of locks or tags, all potentially 

hazardous stored energy or residual energy shall be relieved, disconnected, 

restrained, and otherwise rendered safe. [§1910.147(d)(5)(i).] 

If there is a possibility of re-accumulation of stored energy, verification of energy 

isolation must be continued until the servicing or maintenance work is completed 

or the hazard no longer exists [§1910.147(d)(5)(ii).] 

Monitoring may be accomplished, for example, by visual observation and/or with 

the aid of a monitoring device (test instrument) that will sound an alarm if a 

hazardous energy level is being approached. The standard requires the employer 

to continue to verify isolation when energy leaks may reach dangerous levels. 

This may involve means such as continuous monitoring for the displacement of 

oxygen or the buildup of flammable gases or vapors to concentrations 

approaching and exceeding the lower explosive level of a substance. 

G. Verification of Isolation. Depending upon the measures necessary to detect the 

presence of hazardous energy, the verification of isolation may involve the use of 

a test instrument (e.g., combustible gas indicator), a visual inspection, and/or a 

deliberate attempt to start-up machines or equipment. Authorized employees shall 

take whatever means are necessary to test the machine or equipment to reliably 

verify that isolation and de-energization have been effectively accomplished 

before starting servicing/maintenance work on machines or equipment that has 

been locked or tagged out. [§1910.147(d)(6).] Energy control procedures must 

include these specific requirements for the testing of machine(s) or equipment to 

determine the effectiveness of LOTO devices and other control measures. 

[§1910.147 (c)(4)(ii)(D).] 

Verification must be performed by each authorized employee before starting work 
 4-6

following a shift change unless the employer elects to incorporate the primary 

authorized employee verification system alternative described in Chapter 3, 

Section XV and in Section III.D of this chapter. Specific procedures that will 

ensure the continuity of the LOTO protections during shift or personnel changes 

are required by paragraph (f)(4) of the standard. Paragraph (f)(4) also requires 

specific procedures on the transfer of LOTO device protection between off-going 

employees and on-coming employees. 

NOTE: In multi-shift group LOTO servicing/maintenance operations, 

individual on-coming employees must be provided an opportunity to 

verify that the equipment or machine has been de-energized. The oncoming employees may not depend upon the actions of another 

employee or supervisor from an earlier shift for assurance that the job 

is safe to work. 

H. Servicing/Maintenance. Servicing or maintenance work is performed on the 

locked out or tagged out machine or equipment. 

I. Release from Lockout/Tagout. Release from LOTO shall be accomplished in 

compliance with the requirements at §1910.147(e). 

1. Inspection. The machine or equipment area shall be inspected to ensure that it 

is cleared of nonessential items, which could result in employee injuries, and 

to ensure the machine or equipment components are operationally intact (e.g., 

to check that safeguards are properly applied and functioning). 

[§1910.147(e)(1).] 

2. Employee Removal of Lockout/Tagout Device. Each authorized employee 

must remove their respective lockout or tagout device from the energy 

isolating devices or from the group lock-box(es) following the procedure 

established by the company. [§1910.147(e)(3).] 

3. Employee Positioning. Before re-energization, all employees in the machine 

or equipment area shall be safely positioned or moved from the area. 

[§1910147(e)(2).] 

4. Affected Employee Notification. After the LOTO devices have been 

removed, affected employees must be notified by the employer or an 

authorized employee that the control devices have been removed. This 

notification must be given prior to the starting of a machine or piece of 

equipment. This communication alerts employees that the machine(s) or 

equipment is capable of being started up. [§§ 1910.147 (c)(9) and (e)(2)(ii).] 

J. Re-energization. Energy may be restored to the machine or equipment. 
 4-7

V. Conventional Group Lockout/Tagout Procedures. Conventional group LOTO procedures 

require the affixing of individual LOTO devices by each authorized employee to a group 

LOTO mechanism as discussed in this instruction. The following types of procedures 

and illustrative examples address circumstances ranging from a small group of 

servicing/maintenance personnel during a one-shift operation to a comprehensive 

operation involving many employees over a longer period. These examples are not 

intended to represent the only acceptable procedures for conducting group operations; 

instead, they illustrate several feasible alternatives for having authorized employees affix 

personal LOTO devices in a group LOTO setting. 

Basic Group LOTO – Type A. Each authorized employee places his personal lock or 

tagout device on each energy isolating device and removes it upon completion of the 

assignment. Each authorized employee verifies or observes the de-energization of the 

equipment. 

Personal Lockout

Tagout Devices

DANGER

DO NOT

OPERATE

THIS

EQUIPMENT

SIGNED BY

DATE

DANGER

DO NOT

OPERATE

THIS

EQUIPMENT

SIGNED BY

DATE

Group Lockout 

Tagout Mechanism

Equipment 

Lockout Tagout

OFF

Electric 

Disconnect 

Switch 

LOTO 

Hasp 
 4-8

Master Lockbox/Tagbox – Type B. Under a lock-box procedure, a lock or job-tag with 

tab is placed on each energy isolation device after de-energization. The key(s) and/or 

removed tab(s) are then placed into a lock-box. Each authorized employee assigned to 

the job then affixes his/her personal lock or tag to the lock-box. As a member of a group, 

each assigned authorized employee verifies that all hazardous energy has been rendered 

safe. The LOTO devices cannot be removed or the energy isolating device turned on 

until each individual employee removes their personal lock or tag from the lockbox. 

Then each appropriate key or tab is matched to its lock or tag, and the 

machinery/equipment can be re-energized. 

Personal Lockout

Tagout Devices

Equipment

Lockout Tagout

D

G C

A

Exchanger

P1

P1

P2

P2

B F

E

H

A

E

C

F

G H

B

P1

D

P2

DANGER

DO NOT

OPERATE

THIS

EQUIPMENT

SIGNED BY

DATE

Group Lockout

Tagout Mechanism

Master Lockbox/Tagbox

(keys or tabs)

= Valve

= Pump

= Electric Disconnect

Diagram Legend

Personal Lockout

Tagout Devices

Equipment

Lockout Tagout

D

G C

A

Exchanger

P1

P1

P2

P2

B F

E

H D

G C

A

Exchanger

P1

P1

P2

P2

B F

E

H

A

E

C

F

G H

B

P1

D

P2

A

E

C

F

G H

B

P1

D

P2

DANGER

DO NOT

OPERATE

THIS

EQUIPMENT

SIGNED BY

DATE

DANGER

DO NOT

OPERATE

THIS

EQUIPMENT

SIGNED BY

DATE

Group Lockout

Tagout Mechanism

Master Lockbox/Tagbox

(keys or tabs)

= Valve

= Pump

= Electric Disconnect

Diagram Legend

= Valve

= Pump

= Electric Disconnect

= Valve

= Pump

= Electric Disconnect

Diagram Legend
 4-9

Satellite Lockbox/Tagbox –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 personal lock or tag on the master lockbox. 

Then each principal authorized employee (Crew Leader) inserts his key into a satellite 

lockbox to which each authorized employee in that specific group affixes his personal 

lock or tag. Each 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 within 

the group have been removed from the satellite lock-box can the principal authorized 

employee remove his key from the satellite box and remove his lock from the master 

lock-box. 

Job Lock – Type D. During operations to be conducted over more than one shift (or 

even many days or weeks), a system incorporating a job lock might be used in order to 

ensure continuation of LOTO protection for employees during shift or personnel changes. 

First, a primary authorized employee secures the master lock-box/tag-box with a job-lock 

after all the keys/tag stubs (from the LOTO devices that were affixed to the equipment) 

are inside the lock-box/tag-box. This step is completed before subsequent locks are 

applied to the group LOTO mechanism by the various types of authorized employees as 

described in the above (Type A, B and C) procedures. 

NOTE: A job-lock may have multiple keys if they are in the sole possession of the 

various primary authorized employees (one on each shift). Refer to Chapter 3, 

Section XV for additional information on LOTO continuity devices. 

Personal LockoutTagout Devices

Satellite Lockbox/Tagbox

Group Lockout

Tagout Mechanism

Master Lockbox/Tagbox

Equipment

Lockout-Tagout

A

E

C

F

G H

B

P1

D

P2

Crew

Leader

D

G C

A

Exchanger

P1

P1

P2

P2

B F

E

H

Personal LockoutTagout Devices

Satellite Lockbox/Tagbox

Group Lockout

Tagout Mechanism

Master Lockbox/Tagbox

Equipment

Lockout-Tagout

A

E

C

F

G H

B

P1

D

P2

A

E

C

F

G H

B

P1

D

P2

A

E

C

F

G H

B

P1

D

P2

Crew

Leader

D

G C

A

Exchanger

P1

P1

P2

P2

B F

E

H D

G C

A

Exchanger

P1

P1

P2

P2

B F

E

H
 4-10

Thereafter, each authorized employee, through the established group LOTO procedures, 

affixes their personal lock/tag to a master or satellite (via a principal authorized 

employee) lock-box/tag-box system. After individual LOTO devices are affixed, each 

authorized employee then verifies that all hazardous energy has been rendered safe or the 

primary authorized employee (if designated to do so by the employer's energy control 

procedure) may verify isolation on behalf of a group of authorized employees, as 

described in this chapter. In this manner, the continuity of LOTO protection for 

authorized employees is maintained during shift and during personnel changes while the 

procedure also provides the primary authorized employee flexibility and control over the 

equipment at any appropriate time or shift. 

VI. Alternative Group Lockout/Tagout (Control and Accountability) Procedures. Under most 

circumstances, where servicing or maintenance is to be conducted during only one shift 

by a small number of persons, the installation of each individual's LOTO device would 

not be a burdensome procedure. When complex equipment is being serviced or 

maintained, when there are many sources of energy, and/or when servicing/maintenance 

work extends over more than one work shift, OSHA permits employers to utilize an 

alternative procedure to each employee locking or tagging out each energy isolating 

device. However, consideration must be given to the procedure's organizational structure, 

as previously described, in order to ensure the safety and control of each of the employees 

involved. For example, 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 the adaptation and modification of normal 

group energy control procedures in order to ensure the safety of employees. 

To permit implementation of a pragmatic system, while accommodating 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. Lockout/tagout, blanking, blocking, etc. is 

often supplemented in these situations by the use of work authorization permits and a 

system (e.g., master tagging systems) of continuous employee accountability. For 

example, master tagging systems and work authorization permits are sometimes used to 

supplement hazardous energy control measures (e.g., locks, tags, blanking, blocking) 

through a system that provides for individual employee control and continuous employee 

accountability. 

In evaluating whether the equipment being serviced or maintained is so complex as to 

necessitate a departure from the conventional group lockout/tagout procedures, the 

following factors (often occurring simultaneously) are among those which must be 

evaluated: 

A. Physical size and extent of the equipment being serviced/maintained; 
 4-11

B. Relative inaccessibility of the energy isolating devices; 

C. Number of employees performing the servicing/maintenance; 

D. Number of energy isolating devices to be locked/tagged out; and 

E. Interdependence and interrelationship of the components in the system or between 

different systems. 

Once the equipment is shut down and the hazardous energy has been controlled, 

maintenance/servicing personnel, together with operations personnel, must test the 

machinery or equipment to verify that the isolation of the equipment's energy source(s) is 

effective. The employees may walk through the affected work area to verify isolation. If 

there is a potential for the release or re-accumulation of hazardous energy, verification of 

isolation must be continued. The servicing/maintenance employees 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, use of combustible gas test instruments 

to check for the presence of flammable vapor/gases; flange-breaking techniques, etc.). 

Throughout the maintenance and/or servicing activity, operations personnel normally 

maintain control of the equipment. 

The following procedures are presented as examples to illustrate the implementation of a 

group energy control procedure involving many energy isolating devices and/or many 

servicing/maintenance personnel. Specific issues related to the control of hazardous 

energy in complex process equipment are described below. This 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 many instances where complex process equipment is to be serviced or 

maintained, the process equipment operators 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, cost-effective and orderly sequence. 

C. The operations personnel normally prepare the equipment for LOTO as they 

proceed with the shutdown and identify the locations for blanks, blocks, etc., by 

placing "operations locks and/or tags" (Job Locks) 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. An employer representative or an authorized employee notifies affected 

employees prior to applying LOTO devices. 

E. Upon completion of shutdown, the operations personnel would review the 
 4-12

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 crew(s) would install locks, tags and/or special 

isolating devices at previously identified equipment locations following the 

specified work permit procedure. 

F. 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.) 

G. All of the previous steps must be documented by a master system of 

accountability and should be 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 

employees protected by the master tag if they fully comprehend the details of the 

job and the energy isolation devices actuated or put in place. Signing by the 

respective employees further establishes that energy isolation training relative to 

this operation has been conducted. 

H. After the system has been rendered safe, the authorized employees verify the 

effectiveness of energy controls in controlling hazardous energy. 

NOTE: OSHA has recognized the need for an alternative to the verification 

requirement where complex LOTO operations involve many 

employees and numerous energy isolating devices. In such situations, 

the employer may designate a primary authorized employee (PAE), 

with the responsibility for a set number of employees working under 

the group LOTO device(s). The primary authorized employee must 

implement and coordinate the LOTO of hazardous energy sources and 

verify that the steps taken, in accordance with the specific energy 

control procedure, have in fact isolated the machine or equipment 

effectively from the hazardous energy sources. 

In addition to the primary authorized employee, each authorized 

employee participating in the group LOTO must be informed of his 

right to verify the effectiveness of the lockout measures, and each 

authorized employee must be allowed to personally verify, if he so 

chooses, that hazardous energy sources have been effectively isolated. 

An authorized employee who opts to verify the effectiveness of the 

isolation measures must perform this verification simultaneously with 

or after the PAE verifies the accomplishment of energy isolation and 

after the authorized employee affixes her personal lockout or tagout 

device to the group LOTO mechanism. These steps must be taken 

before authorized employees perform servicing/maintenance activities. 
 4-13

I. 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, reviewed 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 consequently be the responsibility of several 

supervisors. 

J. Upon completion of the tasks required by the work permit, the authorized 

employees' names could 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 so that the accountability of exposed employees is maintained. 

K. 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. 

L. During the progress of the work, inspection audits are conducted. 

M. Upon completion of all work, the equipment is returned to the operations 

personnel after the maintenance and servicing crews have removed their LOTO 

devices, including all completed work permits, and/or special isolating devices 

following the company procedure. 

N. 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. 

O. After the completion of the servicing/ maintenance work, operations personnel 

remove the LOTO devices originally placed to accomplish energy isolation. 

P. After the LOTO devices have been removed, notify affected employees that the 

control devices have been removed. [This notification must be given prior to the 

starting of a machine or piece of equipment to alert affected employees that the 

equipment is capable of being started up.] 

Q. Operations personnel then begin inspection and testing of the equipment prior to 

its being returned to production service. 

In summary, the use of the work permit and/or master tag system, combined with the 

verification of hazardous energy control, work procedures, and walk-through, is an 

acceptable approach to compliance with the group LOTO and shift transfer provisions, as 

long as the control and accountability procedure provides a level of protection equivalent 

to each individual authorized employee affixing her lockout device to the energy isolating 

device. Work authorization permits, when used, must be included as a component of the 

company’s energy control procedure and would additionally require that the company 

procedure clearly contain, in conjunction with other energy control procedures, the 

specific requirements detailed in paragraph 1910.147(c)(4) of the standard. 

 

NOTE: A work authorization permit system fulfilling the Personal Tagout 

(Accountability) Device definitional requirements is considered a Tagout 
 4-14

Device and, as such, all of the tagout provisions of the standard must be met if 

this system is used. This includes additional employee training and additional 

periodic inspection requirements. 

 

Furthermore, as the preceding example procedure illustrates, each employee must sign 

on/off the permit, and the crew leader (Principal Authorized Employee) must present this 

permit documentation to the person responsible for coordinating group LOTO activities 

(Primary Authorized Employee). The crew leader signs off the master tag only after all 

crew members are accounted for and after all of the crew member signatures (i.e., sign 

offs) are obtained on the work permit. To ensure a system of continuous employee 

accountability, the crew leader gives the completed master tag (with signed permit) to the 

primary authorized employee who is responsible for the overall group LOTO procedure 

coordination. 

This work permit example is an extension of and meets the Master Tag definition 

because the crew leader utilizes the work permit as a satellite control and accountability 

mechanism. This is similar to the previously described master and satellite lock-box 

(Type C) example; except that it employs a system of administrative control and 

continuous employee accountability through a master tag and work permit system instead 

of personal LOTO devices on satellite- and master-lock boxes. 
5-1 

Chapter 5 REFERENCES 

General Energy Control References

1. American National Standards Institute; Performance Criteria for Safeguarding for 

Machine Tools, ANSI/ASSE B11.19-2003. 

2. American National Standards Institute; Control of Hazardous Energy – 

Lockout/Tagout And Alternative Methods, ANSI/ASSE Z244.1-2003. 

NOTE: Refer to the November 10, 2004 letter to the Chairman of the Z244 

American National Standards Committee for additional details. 

3. American Petroleum Institute, Management of Process Hazards, API Recommended 

Practice 750. 

4. American Petroleum Institute, Safe Maintenance Practices in Refineries, API 

Publication 2007; 1220 L Street, N.W., Washington, DC. 

5. Oil Industry Advisory Committee, Health and Safety Commission, 1997, The Safe 

Isolation of Plant and Equipment. 

6. U.S. Chemical Safety and Hazard Investigation Board; Investigation Report, Refinery 

Fire Incident, Tosco Avon Refinery, Martinez, California – February 23, 1999; Report 

No. 99-014-I-CA, March 2001.

7. U.S. Chemical Safety and Hazard Investigation Board; Investigation Report, Thermal 

Decomposition Incident, BP Amoco Polymers, Inc. Augusta, Georgia, March 13, 

2001; Report No. 2001-03-I-GA. 

8. U.S. Chemical Safety and Hazard Investigation Board; Investigation Report, Steel 

Manufacturing Incident, Bethlehem Steel Corporation, Burns Harbor Division, 

Chesterton, Indiana, February 2, 2001; Report No. 2001-02-I-IN. 

9. U.S. Department of Health and Human Services, Public Health Service, Centers for 

Disease Control and Prevention, National Institute for Occupational Safety and 

Health, Fatality Assessment and Control Evaluation (FACE) Program; 

http://www.cdc.gov/niosh/face/. 

10. U.S. Department of Health and Human Services, Public Health Service, Centers for 

Disease Control and Prevention, National Institute for Occupational Safety and 

Health, NIOSH ALERT, Preventing Worker Deaths from Uncontrolled Release of 

Electrical, Mechanical, and Other Types of Hazardous Energy, DHHS (NIOSH) 

Publication No. 99-110, August, 1999. http://www.cdc.gov/niosh/99-110.html. 

11. U.S. Department of Labor, Occupational Safety and Health Administration, Control 

of Hazardous Energy (Lockout/Tagout), OSHA 3120, 2002 (Revision). 
5-2 

12. U.S. Department of Labor, Occupational Safety and Health Administration, OSHA’s 

Technical Links to Safety and Health Topics, Control of Hazardous Energy 

(Lockout/Tagout), http://www.osha.gov/SLTC/controlhazardousenergy/index.html. 

13. U.S. Department of Labor, Occupational Safety and Health Administration, OSHA’s 

Technical Links to Safety and Health Topics, Control of Hazardous Energy 

(Lockout/Tagout), LOTO Preamble; http://www.osha.gov/dts/osta/lototraining/ 

preamble/pre-147com.htm 

Vehicle Hazardous Energy Control References

1. American National Standards Institute (ANSI) & Automotive Lift Institute (ALI); 

Safety Requirements for the Operation, Inspection and Maintenance of Lifts; 

ANSI/ALI ALOIM-2000 Standard. 

2. American National Standards Institute (ANSI) & Automotive Lift Institute (ALI); 

Safety Requirements for Installation and Service of Lifts; ANSI/ALI ALIS-2001 

Standard.

3. American National Standards Institute; Portable Hydraulic Jacks for Automobiles, 

ANSI JIS D 8101. 

4. American National Standards Institute; Portable Screw Jacks for Automobiles, ANSI 

JIS D 8103. 

5. American National Standards Institute; Lifts Above Ground for Automobiles, ANSI 

JIS D 8108. 

6. Automotive Lift Institute; LIFTING IT RIGHT, SAFETY MANUAL (ALI /SM01-1). 

7. Automotive Lift Institute (ALI); Safety Tips Cards (ALI ST90). 

8. Control of Hazardous Energy (Lockout/Tagout); OSHA Publication 3120. 

9. National Automobile Dealers Association (NADA), Lockout/Tagout Bulletin. 

10. National Fire Protection Association, Standard for Repair Garages; NFPA 88B. 

11. National Institute for Occupational Safety and Health (NIOSH 77-229, NITS #PB 

276-677); Good Practices for Employees in Auto Body Shops. 

12. NIOSH Health Safety Guide 75-136 (NITS #PB 83-178-210); Auto Repair & Body 

Shops. 

13. National Safety Council; Automotive Hoisting Equipment Data Sheet. 

14. State of Oregon Rules for Commercial and Industrial Vehicles, Standard OAR 437-

002-0223. 

15. U.S. Department of Labor, Occupational Safety and Health Administration (OSHA); 

Hazards While Servicing Light Trucks, Automobile, and Other Small Tires; Safety 

and Health Bulletin 04-29-2004. 
5-3 

16. U.S. Department of Labor, Occupational Safety and Health Administration (OSHA); 

Servicing Single-Piece and Multi-Piece Rim Wheels; OSHA Publication 3086. 

17. OSHA; Safety Hazard Information Bulletin, Automobile Air Bag Safety, August 30, 

1990 Regional Administrator memorandum. 

18. OSHA, Technical Links, Autobody and Refinishing, (www.oshaslc.gov/SLTC/autobody). 

19. Underwriters Laboratories Inc., UL 201, Standard for Garage Equipment, Vermont 

Pollution Prevention Division; Occupational Safety and Health in the Automotive 

Repair Business, “A Quick Reference Guide”.