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Regulations (Preambles to Final Rules) - Table of Contents
• Record Type: Control of Hazardous Energy Sources (Lockout/Tagout)
• Section: 3
• Title: Section 3 - III. Accident Data

III. Accident Data

The collection of data on accidents resulting from a failure to utilize proper lockout or tagout procedures is hampered because many accidents are not reported; are reported only locally; or are reported and categorized under other causal factor categories (such as "caught-in" or"caught-between"). Incorrect or incomplete categorization is particularly true for lockout related accidents, since many of the injuries are grouped under the more commonly used classifications such as, burns, electrocutions, lack of machine guarding or equipment failure.

OSHA also recognizes that there has been some underreporting of accident data -- either inadvertent or intentional. As a result, OSHA believes that the data available represent only a portion of the total injuries and fatalities that have occurred. However, OSHA believes that the accidents which have been recorded or reported and investigated or studied as being "lockout related" provide a graphic illustration of the extent of the problem, the causal factors, the distribution of accidents in industry, and the type and severity of injuries resulting from those accidents.

There have been several studies conducted to determine the magnitude and extent of the problem. These studies were conducted by: (a) The U.S. Department of Labor, Bureau of Labor Statistics; (b) OSHA's Office of Data Analysis (formerly Office of Statistical Studies and Analysis); (c) the National Institute for Occupational Safety and Health (NIOSH); (d) OSHA's Office of Experimental Programs; and (e) OSHA's Office of Mechanical Engineering Safety Standards. During the hearing, the UAW provided detailed data on fatalities and injuries (Tr. p. H216, H253), which they expanded upon in their post-hearing submission (Ex./ 3-49). The studies are discussed in the following paragraphs.

A. Bureau of Labor Statistics Work Injury Report Study. The first study examined by OSHA was the Work Injury Report Study entitled "Injuries Related to Servicing Equipment" [Ex. 33]. This study is a compilation of reports of accidents and follow-up survey questionnaires sent out by the Bureau of Labor Statistics (BLS). The survey, conducted from August to November 1980, covered workers who were injured while cleaning, repairing, unjamming or performing other non-operating tasks on machines, equipment and electrical or piping systems. BLS identified accidents from 25 participating states, and mailed each of the injured employees a follow-up questionnaire containing inquiries about the specific details of his/her accident. There were 1,285 questionnaires sent out and 833 (approximately 65 percent) of the employees responded. Not all questions were responded to by all participants, since many of the questions related to situations which may not have been relevant to the circumstances of each injury. In some instances, many of the respondents also gave multiple responses to a single question.

Tables I through VI present tabulations of the results of the BLS Work Injury Report Study.

Industry Workers Percentages (1)
Total 833 100
Div A -- Agriculture, forestry and fishing 1
B -- Mining 1 ..............
C -- Construction 35 4
D -- Manufacturing 619 74
E -- Transportation and public utilities 19 2
F -- Wholesale trades 57 7
G -- Retail trades 31 4
H -- Finance, insurance and real estate 8 1
I -- Services 43 5
J & K -- Others 8 1
Total (2) 794 100
1 to 19 employees 159 20
20 to 49 employees 123 15
50 to 99 employees 120 15
100 to 499 employees 234 29
500 or more employees 158 20
(1) Due to rounding, percentages may not add to 100.
(2) The total of each table represents the number of respondents answering the pertinent question(s) of the survey.

Occupation Workers Percent
Total 833 100
Operators, excluding transport 373 45
Craft and kindred workers 281 34
Laborers, excluding farm 94 11
Service workers, excluding private household 19 2
Clerical and kindred workers 19 2
Managers and administrators 13 2
Professional, technical & kindred 12 1
Transport equipment operators 10 1
Farm laborers and supervisors 8 1
Nonclassified 4 (1)
(1) Less than .5.
Note. -- Due to rounding, percentages may not add to 100.

  Workers Percent
833 100
Unjamming objects from equipment 250 30
Cleaning equipment 245 29
Repairing equipment 77 9
Performing maintenance (oiling, etc.) 34 4
Installing equipment 13 2
Adjusting equipment 99 12
Doing set-up work 57 7
Performing electrical work 29 3
Inspecting equipment 15 2
Testing material or equipment 2 (1)
(1) Less than .5 percent.

  Workers Percent
833 100
Injured by moving machine part 735 88
Injured by contact with energized electric parts 45 5
Injured by burners, hot liquids or other hazardous materials 29 3
Injured by falling machine parts 10 1
Other 14 2
833 100
No 653 78
Yes 180 22
(2)592 (2)
Worker felt it would slow down production or take too long 112 19
Not required by company procedure 69 12
Worker did not know how to 8 1
Did not think it necessary 209 35
Task could not be done with power off 209 35
Worker did not realize power was on 62 10
Other reasons 61 10

a. What happened at the time of injury?
176 100
Injured employee accidentally turned equipment on 20 11
Co-worker accidentally turned equipment on 15 9
Co-worker turned equipment on, not knowing equipment was being worked on 56 32
Equipment or material moved when jam-up cleared 9 5
Parts were still in motion (coasting) 30 17
Other reason 46 26
b. Were additional steps taken to de-energize equipment?
(2)160 (2)
No -- not necessary 49 31
No -- not required by company 23 14
No -- would slow down production 8 5
No -- worker did not have tools 4 2
No -- other reason 20 13
No -- reason not given 37 23
Disconnected main power 14 9
Tagged out equipment power controls 6 4
Locked out(3), installed blank flange or removed fuse 3 2
Disconnected electric line 5 3
Drained pressure or hazardous material 9 6
Other 11 6
(1) Due to rounding percentages may not add to 100.
(2) Because more than one response is possible the sum of the responses and percentages may not equal the total number of persons who answered the question.
(3) The two accidents which occurred after the equipment was locked out took place because (1) the lockout had been done to the wrong power line and (2 a second power line had been spliced into the wiring beyond the lockout.

  Workers Percent
554 100
Yes 214 39
No 340 61
273 100
Provided print instructions 25 9
Procedures posted on equipment 37 14
Instruction given as part of on-the-job training 176 64
Formal training given at meeting, etc. 28 10
Other 7 3
186 100
After the accident (1)15 (1)8
One to six months before accident 36 19
Six months to a year before accident 28 15
Upon hiring 84 45
Over a year before accident 60 32
(1) Because more than one response is possible, the sum of the responses and percentages may not equal the total. Percentages are calculated by dividing each number of responses by the total number of persons who answered the question.

Number of lost workdays
Workers Percent
Total 793 100
No time lost 107 13
1 to 5 workdays lost 132 17
6 to 10 workdays lost 95 12
1 to 15 workdays lost 75 9
16 to 20 workdays lost 47 6
21 to 25 workdays lost 47 6
26 to 50 workdays lost 60 8
51 to 40 workdays lost 49 6
41 to 60 workdays lost 54 7
More than 60 workdays lost 41 5
No indication of number of lost workdays 86 11

B. Analysis of 83 Fatality Investigations by OSHA's Office of Data Analysis.

The second study examined by OSHA was the compilation of data from 83 fatality investigations conducted by OSHA between 1974 and 1980. This report is entitled "Selected Occupational Fatalities Related to Lockout/Tagout Problems as Found in Reports of OSHA Fatality/Catastrophe Investigations" [Ex. 3 5]. All of these accidents were identified as having been caused by failure to properly deenergize machines, equipment or systems prior to performing maintenance, repairs or servicing.

Tables VII through IX present tabulations of the results of the OSHA analysis of 83 fatality investigations.

Cause Number Percent
Lack of adherence to safe work practices (no procedure or failure to follow procedure) 83 100
Accidental or inadvertent activation 21 35
Failure to deactivate 29 25
Equipment failure 27 8
Other 5 6

NOTE. -- Due to rounding, percentages may not add to 100.

Agent Number Percent
Total 83 100
Agitators and mixers 12 14
Rolls and rollers 11 13
Conveyors and augers 11 13
Saws and cutters 11 13
Hoists 8 10
Earth moving equipment 6 7
Crushers and pulverizers 4 5
Forges and presses 4 5
Electrical apparatus 4 5
Vehicles 3 4
Other 9 11

Activity Number Percent
  83 100
Conducting normally assigned duties 69 83
Conducting other duties 14 17

In analyzing the 83 fatality investigation reports and assigning causes to each accident, no attempt was made to draw conclusions or inferences beyond the information contained in the reports. For example, if the employee was killed in operating machinery, unless the report stated otherwise, the cause of the accident was considered to be failure to shut off the machine, rather than a combination of causal factors such as failure to sit off the machine, failure to lockout, failure to document adequate procedures, and failure to provide sufficient employee training. Additionally, if a machine was found to be running, it was assumed that the employee failed to shut off the machine rather than that another employee restarted the machine.

C. Analysis of 125 Fixed Machinery Fatalities by OSHA's Office of Data Analysis. A Separate study by OSHA's Office of Data Analysis is entitled "Occupational Fatalities Related to Fixed Machinery as Found in Reports of OSHA Fatality/Catastrophe Investigations" [Ex. 3-6]. This study contained an analysis of investigative reports of 125 fatalities involving fixed machinery which occurred between 1974 and 1976, and which were investigated by OSHA. The primary causal factors under which the accidents were classified were operating procedures, accidental activation, lack of machine deactivation, equipment failure, and other causes.

The following is a tabulation of the results of this study.

Causal factor Number Percent
Total 125 100
Failure to adhere to safe operating procedures 41 33
Accidental machine activation 31 25
Machine not deactivated 23 18
Equipment failure 21 17
Other 9 7

D. National Institute for Occupational Safety and Health, Guidelines for Controlling Hazardous Energy During Maintenance and Servicing and Study of Hazardous Release of Energy Injuries in Ohio in 1983. The next studies considered by OSHA were done by the National Institute for Occupational Safety and Health (NIOSH) [Ex. 4 and 2-80c]. In the first, fifty-nine out of a total of 300 accident reports were analyzed to illustrate situations in which adequate control of energy might have prevented the accidents. These case files were selected because they contained sufficient detail to enable NIOSH to evaluate the accidents and determine what countermeasures might have been available to prevent the accidents.

The report indicated that these types of accidents are preventable if effective energy control techniques are available. the workers are trained to use them, and management provides the motivation to ensure their use.

The following is a tabulation of the results of the first study.

Factor Number Percent
Total 59 100
Failure to deenergize machine or control energy 27 46
Accidental reenergization 25 42
Ineffective energy isolation 6 10
Disregarding residual energy 1 2

The NIOSH draft report, undated, entitled: "Study of Hazardous Release of Energy Injuries in Ohio in 1983" (Ex 2-80c).

This report contains information on 339 accidents which occurred in the state of Ohio in 1983. These accidents were selected because: (1) They fell into likely categories of industry, occupation, type of accident, source of injury and diagnosis of injury; (2) the worker's compensation claim narrative suggested applicability; and (3) questionnaire responses by plant officials positively identified the injuries as resulting from an unexpected energy release during equipment repair, servicing or maintenance. The report defined an unexpected or unwanted release of energy "as when a press closes on an operator's hand or when steam escapes from a broken pressure line."

The "Ohio Study" was submitted by NIOSH in draft form. OSHA is not aware of whether the study results have since been finalized by NIOSH, or whether any further effort has been expended to follow-up on its findings. However, OSHA has evaluated the draft study and has determined that few definite conclusions can be drawn from the available data. For example, most of the injuries reported in the study (70%) occurred to production workers as a result of servicing which took place during normal production operations. Although the study indicated that firms where injuries occurred used tagout, it did not indicate whether either tagout or tagout procedures were applied in situations where production employees were performing servicing work, as well as maintenance employees. Without such information, it is not possible to determine whether the tagout procedure failed in situations where it was being applied, or whether tagout (or other type of employee protection, such as shutting down the equipment) was in use at the time of the accident. In addition, the study only considered the issue of locks versus tags, and did not evaluate the other elements of the lockout or tagout programs in place. As OSHA has emphasized the adequacy of a program for the control of hazardous energy relies on much more than whether a lockout device or a tagout device issued on the energy isolating means. Therefore, the Agency has determined that the draft Ohio study raises many more questions than it answers, and that no solid conclusions can be drawn from the data provided to date. OSHA encourages NIOSH to continue its review and analysis of this study, and looks forward to receiving a final version of the study after a full evaluation and revision has been performed.

The following is a tabulation of the usable results of this study.

Task Number Percent
Unjamming object 84 25
Cleaning equipment 75 22
Repairing equipment 41 12
Adjusting equipment 41 12
Doing set-up work 27 8
Inspecting equipment 11 3
Testing equipment 9 3
Installing equipment 9 3
Electrical work 8 2
Other tasks 34 10
Total 339 100

Equipment mode Number Percent
Production mode 230 70
Maintenance mode 99 30
Total (1) 329 100

(I) Ten respondents did not identify the equipment mode.

F. Analyses of Fatality/Catastrophe Reports and General Duty Clause Citations by OSHA's Offices of Experimental Programs and Mechanical Engineering Safety Standards.

There were two additional OSHA studies which were conducted jointly by the Office of Experimental Programs and the Office of Mechanical Engineering Safety Standards. These studies were compilations and analyses of OSHA Form 36 reports [Ex. 3-7] and OSHA 5(a)(1) citations [Ex. 3-8], respectively.

An OSHA Form 36 (Preliminary Fatality/Catastrophe Event Report) is prepared each time an Area Office is notified of a serious accident resulting either in a fatality or in serious injury to five or more employees that necessitates their hospitalization. This report is used to determine whether or not OSHA will conduct an investigation of the circumstances surrounding the accident. Since OSHA does not receive notification of all accidents resulting in a fatality or catastrophe, the total number of Form 36 reports received does not equal the total number of workplace fatalities and serious injuries which occurred during this study period. However, OSHA believes that the causes of, and the circumstances leading to, the accidents clearly demonstrate the nature and seriousness of lockout/ tagout-related accidents.

The OSHA Form 36 study which analyzed data reported during the period 1982-1983 [Ex. 3-7], utilized a list of 443 fatalities. From these fatalities, all of which occurred in industries subject to the present regulations, it was determined that 36 (8.1 percent) would have been prevented by the use of an effective lockout or tagout procedure.

The second study [Ex. 3-8] used information developed by OSHA's Office of Mechanical Engineering Safety Standards which identified, categorized and recorded "general duty clause" (section 5(a)(1) of the OSHA Act) citations from 1979 to 1984. A general duty clause citation is issued when, during an inspection, a "recognized hazard" is detected which is causing or is likely to cause death or serious physical harm to an employee, but which is not addressed in an OSHA standard applicable to that industry.

The citations in the latter study have been broken down between maritime, construction, and general industry. The general industry citations were further subdivided to reflect the nature of the hazard which the citation addressed, such as hazardous materials or material handling. When there was special Agency interest in an industry or hazard, the citations were further broken down by industry sector (such as oil and gas well drilling).

From 1979 through 1984, 3,638 inspections were conducted which resulted in the issuance of general duty clause citations. Of these 3,638 inspections, there were 376 inspections in which the failure to control hazardous energy was cited. Hence, in approximately 10 percent of all inspections which resulted in the issuance of at least one General Duty clause citation, herein referred to as a 5(a)(1) citation, failure to lockout or tagout was identified. [Ex. 3-8]

The following is a tabulation of the breakdown of lockout citations by industry division.

Industry divisions Number of citations Percent
Total 376 100
A -- Agriculture, forestry and fishing 2 .5
B -- Mining 4 1.1
C -- Construction 18 4.8
D -- Manufacturing 310 82.4
E -- Transportation and public utilities 11 2.9
F -- Wholesale trades 14 3.7
G -- Retail trades 5 1.3
H -- Finance, insurance and real estate 0 0
I -- Services 12 3.2
J -- Public administration 0 0
K -- Not otherwise classified 0 0
Unknown 0 0

Note. -- Due to rounding, percentages may not add to 100.

At the hearing, the International Union, United Automobile, Aerospace and Agricultural Implement Workers of America (UAW) testified that there were 74 fatalities which it referred to as "lockout fatalities," which had occurred to its members between 1973 and 1988 (Tr. H253). In response to requests at the hearing, the UAW provided additional information on these fatalities (Ex. 49E). (The number of "lockout fatalities" was revised to 72 in the post-hearing submission.) The post-hearing data reinforce OSHA's determination that fatalities from hazardous energy sources involve more than simply a failure to "lock out" machines or equipment. Of the 72 fatalities, UAW reported that there had been "inadequate training" in 49 cases (68%); "inadequate procedures" in 50 cases (69%); and "adequate, but unenforced procedures" in 19 cases (26%). Although OSHA agrees that lockout provides more security against reenergization of equipment than tagout, the Agency is convinced more than ever that there is much more to energy control than the question of lockout vs. tagout. The UAW data make a strong case for the need for OSHA to provide for proper energy control procedures and adequate training in those procedures.

In the proposal, OSHA estimated, based on BLS data, that lockout or tagout related fatalities represented 7% of the total number of occupational fatalities. In their post-hearing comment, the UAW indicated that for their workers, this figure is estimated to be 26%, and that OSHA should take this larger estimated percentage into account in its projections. The UAW also argued that its data base is larger than that used by OSHA, and that it is more reliable because of its national scope and inclusion of both large and small facilities. (Ex. 49A). OSHA appreciates the time and effort taken by the UAW in compiling such data and in submitting it to the rulemaking record. At the time of the proposal, the Agency acknowledged that its injury and fatality figures were likely to be understated for various reasons. Regardless of whose figures are used, there is little doubt that the failure to control hazardous energy sources exposes employees to a significant risk, and that this standard is necessary to reduce those risks.

Regulations (Preambles to Final Rules) - Table of Contents

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