ML19308B763

Events & Casual Factors Charting, Prepared for DOE

ML19308B763
Person / Time
Site:	Crane
Issue date:	08/31/1978
From:	Buys J, Clark J EG&G, INC.
To:
References
TASK-TF, TASK-TMR DOE-76-45-14, SSDC-14, NUDOCS 8001170258
Download: ML19308B763 (42)

Text

DOE 76-45/14 SSDC-14 l

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EVENTS AND CASUAL FACTORS CHARTING 1

1 SYSTEM SAFETY DEVELOPMENT CENTER b

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@ ooE EG&G Idaho, Inc.

hiah Iall Ifat< 81401 P00R~0RIGINAL 2

August 1978 1

UNITED STATES DEPARTMENT OF ENERGY O

DIVISION OF OPERATIONAL AND ENVIRONMENTAL SAFETY l

8001170 2 5 8

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DISCLAIMER This report was prepared as an account of work sponsored by the United States Government.

Neither the United l

States nor the United States Department of Energy nor any of their employees, nor any of their contractors, subcontractors, or their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product or process disclosed, or represents that its use would not infringe privately owned rights.

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P00RBRERR Available from:

System Safety Development Center EG&G Idaho, Inc.

P. O. Box 1625 Idaho Falls, Idaho 83401 l

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DOE 76-45/14 SSDC-14 UC-41 4

EVENTS AND CAUSAL FACTORS CHARTING 1

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J. R. Buys J. L. Clark i

Work Performed At EG&G IDAH0, INC.

IDAHO OPERATIONS OFFICE Under Contract No. E-76-C-07-1570 1

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ACKNOWLEDGMENTS Special acknowledgment is extended to the staff of the System Safety Development Center and to reviewers throughout the Department of Energy complex for their helpful. suggestions and guidance, and to Della Kellogg for her editorial assistance.

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CONTENTS l

AC KNOWLE DGMENTS..........................

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INTRODUCTION.........................

1 2.

NATURE OF ACCIDENT INVESTIGATION...............

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3.

DESCRIPTION OF TECHNIQUE...................

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I 3.1 Suggested Format l

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3.2 Criteria for Events Descriptions 6

i 3.3 Typical Application...................

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BENEFITS OF THE TECHNIQUE 7

1 4.1 General Purposes of Investigation Served By E&CF Charting 7

4.2 Role of E&CF Charting in Conducting the Inves ti ga ti on......................

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4.3 Use of the E&CF Chart in Preparing the Report......

10 5.

PRACTICAL APPLICATION 11 6.

REFERENCES..........................

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i APPENDIX A GENERALIZED EVENTS AND CAUSAL FACTORS CHART.................... A-1 APPENDIX B GAS PIPELINE ACCIDENT................ B-1 4

1 APPENDIX C FARM TRACTOR ROLLOVER................ C-1 APPENDIX D LOX TANK EXPLOSION.................. D-1 4

l APPENDIX E X-RAY EXPOSURE ACCIDENT............... E-1 1

APPENDIX F GRINDING WHEEL DISINTEGRATION............ F-1 i

APPENDIX G PENINSULA ACCIDENT.................. G-1 APPENDIX H ALIGNMENT PIT ACCIDENT................ H-1 O

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O FIGURES 1.

Events and causal factors relationships 5

2.

Events and causal factors chart example 8

3.

Events and causal factors wall display............

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INTRODUCTION V

The goal of the Department of Energy (D0E) to build and maintain a comprehensive safety management program includes an accident investigation process that utilizes state-of-the-art investigative and analytical methods.

Accidents are investigated to identify the causes of their occurrence and to determine the actions that must be taken to prevent recurrence.

It is essential that the accident investigators probe deeply into both the events and the conditions that create accident situations, and also the managerial control systems that let them develop so that the root accident causes can be identified.

Identification of these root causes necessitates understanding the interacting of events and causal factors through a time-sequenced chain of activity from an initiating event through the final loss producing occurrence. Vital factors in accident causation emerge as sequentially and/or simultaneously occurring events, which interact with existing condi-tions, are traced out to reconstruct the multifactorial path to unacceptable loss. A meticulous trace of unwanted energy transfers [a basic Management Oversight and Risk Tree (MORT) concept in accident causation] and their relationships to each other and to the people, plant, procedures, and controls implicated in accident occurrence further reveals a well-defined sequence in accident development.

Ludwig Benner[l3 suggests two basic foundation principles which are helpful in defining and understanding these sequences of events, conditions, O

and energy transfers.

b (1) Accidents are the results of a set of successive events that produce unintentional harm (i.e., personal injury, property damage, etc.).

(2) The accident sequence occurs during the conduct of some work activity (i.e., a series of events directed toward some anticipated or intended outcome other than injury ordamage).

The key points, then, are that an accident involves a sequence of events (happenings) that occur in the course of good-intentioned work activity but that culminate in unintentional (not willful) injury or damage.

Implicit here, too, is the existence of contributing causative factors, such as existing conditions, energy flows, failed barriers, etc., as well as identifiable beginning and ending points in the accident sequence.

Benner and his colleagues at the National Transportation Safety Board (NTSB) pioneered the use of sequence diagrams or charts as analy-tical tools in accident investigation. Their work led to the development of the Events and Causal Factors (E&CF) chart (or diagram), which depicts in logical sequence the necessary and sufficient events and causal factors for accident occurrence.

It can be used not only to analyze the accident and evaluate the evidence during investigation, but also can help validate the accuracy of preaccident systems analyses.

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The E&CF sequence ctjarting technique is an integral and important part of the MORT-based [2J DOE accident investigation process.

It is used in conjunction with other key MORT tools, such as MORT tree analysis, change analysis, and energy trace and barrier analysis, to achieve optimum results in accident investigation. E&CF charting has been used success-fully as a focal point of analysis on several ERDA and DOE accident and incident investigations with excellent results. The fundamentals of this valuable MORT tool are discussed in this monograph.

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NATURE OF ACCIDENT INVESTIGATION Experience has shown that accidents are rarely simple and almost never result from a single cause. Rather, they are usually multifactorial and develop from clearly defined sequences of events which involve performance errors, changes, oversights, and omissions. The accident investigator (or the investigating board or committee) needs to identify and document not only the events themselves, but also the relevant conditions affecting each event in the accident sequence. To accomplish this, a simple, straight-forward approach can be utilized which breaks down the entire sequence into a logical flow of events from the beginning of accident development to the end (which may be defined either as the loss event itself or as the end of the amelioration and rehabilitation phase).

This flow of events need not lie in a single event chain but may involve confluent and branching chains.

In fact, the analyst / investigator often has the choice of expressing the accident sequence as a gruup of confluent event chains which merge at a coninon key event, or as a primary chain of sequential events into which causative factors feed as conditions that contribute to event occurrence, or as a combination of the two.

Construction of the E&CF chart should begin as soon as the accident investigator begins to gather factual evidence pertinent to the accident sequence and subsequent amelioration. The events and causal factors will usually not be discovered in the sequential order in which they occurred, so the initial E&CF chart will be only a skeleton of the final product and will need to be supplemented and upgraded as additional facts are gathered.

Even though the initial E&CF chart will be very incomplete and contain many information deficiencies, it should be started very early in the accident investigation because of its innate value in helping to:

(1) Organize the accident data.

(2) Guide the investigation.

(3) Validate and confirm the true accident sequence.

(4)

Identify and validate factual findings, probable causes, and contributing factors.

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(5) Simplify organization of the investigation report.

(6)

Illustrate the accident sequence in the investigation report.

With all its virtues as an independent analytic technique E&CF charting is most effective when used with the other MORT tools that pro-vide supportive correlation. Causal factors on the E8CF chart should be checked by comparison with the prime deficiencies identified by MORT chart based analysis.

Critical changes revealed through change analysis interface with key events and causal factors in the E&CF chart in establishing sequence chains.

A meticulous trace of unwanted energy transfers and their interrelationships facilitates:

(1) Questioning and testing of accident hypothesis.

(2) Use of barrier analysis to examine possible energy flow interruptions.

(3)

Identification of energy channels which lead directly to injury or damage or contribute to their occurrence.

O An appropriate combination of the major MORT analytic tools, including E&CF charting, provides the core for a good investigation.

3.

DESCRIPTION OF TECHNIQUE [3]

Several examples of E&CF charting which illustrate different construc-tion methods of varying complexity, sophistication, and clarity are shown in Appendices A through H.

As can be seen from these appendices, strict adherence to specific rules for developing sequence diagrams has not been followed in the past, nor is such adherence necessary now.

In applying the technique as an analytical tool, people have generally used whatever seemed to work best for them and that is still a valid approach.

There is, however, adequate justification for adopting some general guidelines for developing E&CF charts for DOE investigation reports.

First, they will help achieve the goal of increased comparability and consistency in accident reporting within the DOE complex. Addition-ally, there is such a wide variety of operational activities within DOE and such a wide range of experience and technical expertise among the personnel who conduct accident investigations that the unifying influence of common guidelines for individual analysts is needed for meaningful communications.

It is intended that these guidelines be as simple as v

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possible while preserving the effectiveness of the E&CF chart as a key analytical tool.

It is further intended that investigators be provided with helpful guidelines without inhibiting their use of this tool by imposing too many or too complex rules.

Consistent with these intentions, then, the following guidelines are suggested for use in constructing E&CF charts for accident analyses and inclusion in investigation reports.

3.1 Suggested Format 3.1.1 Events should be enclosed in rectangles,

,and cc,ditions in ovals.

3.1.2 Events should be connected by solid arrows, w

3.1.3 Conditions should be connected to each other and to events by dashed arrows.

3.1.4 Each event and condition should either be based upon valid factual evidence or be clearly indicated as presumptive by dashed line rectangles and ovals.

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3.1.5 The primary sequence of events should be depicted in a straight horizontal line (or lines in confluent or branching primary chains) with events joined by bold printed connecting arrows.

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3.1.6 Secondary event sequences, contributing factors, and systemic factors should be depicted on horizontal lines at different levels above or below the primary sequence (see Figure 1).

3.1.7 Events should be arranged chronologically from left to right.

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3.1.8 Events should track in logical progression from the beginning to the end of the initiation-preaccident-accident-amelioration sequence and should include all pertinent occurrences.

This necessitates that the beginning and the end be defined for each accident sequence. Analysts frequently use the accident as the key event and proceed from it in both directions to reconstruct the preaccident and postaccident E&CF sequences.

3.2 Suggested Criteria for Event Descriptions 3.2.1 Each event should describe an occurrence or happening and not a condition, state, circumstance, issue, conclusion, or result; i.e., " pipe wall ruptured", not "the pipe wall had a crack in it".

3.2.2 Each event should be described by a short sentence with one subject and one active verb; i.e., " mechanic checked front end alignment",

not " mechanic checked front end alignment and adjusted camber on both front wheels".

3.2.3 Each event should be precisely described; i.e., " operator pulled headlight switch to 'on' position", not " operator turned lights on".

3.2.4 Each event should describe a single, discrete occurrence; i.e., " pipe wall ruptured", not " internal pressure rose and pipe wall ruptured".

3.2.5 Each event should be quantified when possible; i.e., " plane descended 350 feet", not " plane lost altitude".

3.2.6 Each event should be derived directly from the event (or events in the case of a branched chain) and conditions preceding it; i.e., " mechanic adjusted camber on both front wheels" is preceded by

" mechanic found incorrect camber" which is preceded by "nechanic checked front end alignment" - each event deriving logically from the one preceding it.

When this is not the case, it usually indicates that one or more steps in the sequence have been left out.

3.3 Typical Application Application of the suggested format and event description criteria for constructing a typical E&CF chart of a simple accident is illustrated in the following example.

3.3.1 Accident Description. Ajax Construction Company was awarded a contract to build a condominium on a hill overlooking the city.

Prior to initiation of the project, a comprehensive safety program was developed covering all aspects of the project.

Construction activities began on Monday, October 4, 1976, and proceeded without incident through Friday, October 8,1976, at which time the project was shut down for the weekend.

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Ob At that time, several company vehicles, including a 2-1/2-ton dump truck, were parked at the construction site. On Saturday, October 9, 1976, a nine-year-old boy, who lives four blocks from the construction site, climbed the hill and began exploring the project site.

Upon finding the large dump truck unlocked, he climbed into the cab and began playing with the vehicle controls. He apparently released the energency brake and the truck began to roll down the hill. The truck rapidly picked up speed.

The boy was afraid to jump out and did not know how to apply the brakas.

The truck crashed into a parked auto at the 'oottom of the hill. The truck remained upright, but the boy suffered serious cuts and lacerations and a broken leg. The resultant investigation revealed that, although the safety program specified that unattended vehicles would be locked and the wheels chocked, there was no verification that these rules had been communicated to the drivers.

3.3.2 Discussion (see Figure 2). You will note that events are in time-sequenced order, that each follows logically from the one preceding, and that dates are indicated when known. Events are enclosed in rectangles and the conditions in ovals.

Event statements are characterized by single subjects and " active" verbs.

(In some events, the subject is implied only.)

The primary sequence of events is identified by bold printing the connecting arrows. Other events are connected by solid arrows and conditions by dashed arrows. The " rules not communicated to drivers", " internal communi-cations LTA", and " management control LTA" conditions and the " accidentally O

released brakes" event are enclosed in dashed ovals and a dashed rectangle,

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respectively, to indicate that the information is presumptive. The sequence was terminated at the accident but could have been extended to include amelioration (i.e., rescue, emergency action, medical services, rehabili tation, etc.).

Further application of these principles are shown in the generalized E&CF charts in Appendix A.

4.

BENEFITS OF THE TECHNIQUE Use of the E&CF charting technique by the accident investigator provides benefits in:

(1) meeting the general purposes of accident investigation, (2) conducting the investigation, and (3) writing the investigation report.

4.1 General Purposes of Investigation Served By E&CF Charting The primary purpose of accident investigation is to determine what happened and why it happened in order to prevent similar occurrences and to improve the safety and officiency of future operations. When serious I

accidents occur, they are of ten symptomatic of systemic. deficiencies j

which also downgrade performance and production. When the accident is used as a window through which to view the existing management system, these deficiencies are revealed and benefits are derived which go far beyond correction of the immediate causes of the accident.

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'N from which practical corrective actions can be derived to upgrade total perfonnance. The intent of the investigation, then, is not to place blame, but rather to determine how responsibilities can be clarified and how loss-producing errors can be reduced and controlled. Accurate E&CF charting can help satisfy these purposes in the following ways:

(1) Provide a cause-oriented explanation of the accident.

(2) Provide a basis for beneficial changes to prevent future accidents and operational errors.

(3) Help delineate areas of responsibility.

(4) Help assure objectivity in the conduct of the investigation.

(5) Provide an organization of quantitative data (e.g., time, velocity, temperature, etc.) related to loss-producing events and conditions.

(6) Provide an operational training tool.

i (7) Provide an effective aid to future systems design.

4.2 Role of E&CF Charting in Conducting the Investigation E&CF charting contributes the following useful aids to conducting accident investigations in a professional manner:

(1) Aids in developing evidence, in detecting all causal factors through sequence development, and in determining the need for in-depth analysis.

(2) Clarifies reasoning.

(3)

Illustrates multiple causes. As previously stated, accidents rarely have a single "cause".

Charting helps illustrate the multiple causal factors involved in the accident sequence, as well as the relationship of proxi-mate and remote, and direct and contributory causation.

(4) Visually portrays the interactions and relationships of all involved organizations and individuals.

(5) I'.lustrates the chronology of events showing relative sequence in time.

(6) Provides flexibility in interpretation and summarization of collected data.

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(7) Conveniently communicates empirical and derived facts in a logical and orderly manner.

(8) Links specific accident factors to organizational and management control factors.

4.3 Use of the E&CF Chart in Preparing the Report The purpose of the investigation report is to convey the results of the investigation in clear and concise language. The investigation report constitutes a record of the occurrence by which the investigation is measured for thoroughness, accuracy, and objectivity.

The report should also fully explain the technical elements of the causal sequences of the occurrence and describe the management systems which should have prevented the occurrence. Use of E&CF charting has been effective in satisfying these report objectives.

Specific advantages provided are as follows:

(1) Provides a check for completion of investigative logic.

Even the most elementary types of sequence charting can reveal gaps in logic and help prevent inaccurate conclusions.

(2) Provides a method for identification of matters requiring further investigation or analysis.

Significant event blocks with vague or nonexistent causal factors can alert the inves-tigator to the need for additional fact-finding and analysis.

(3) Provides a logical display of facts from which valid conclu-sions can be drawn.

(4) Provides appropriate and consistent subject titles for

" discussion of facts" and " analysis" paragraphs.

(5) Provides a method for determining if the general investiga-tive purposes and specific objectives have been adequately met in terms of the conclusions reached.

(6) Provides a method for differentiation between the analysis of the facts and the resultant conclusions.

(7) Presents a simple method for clearly describing accident sequences and causes to a reading audience with divergent backgrounds. Without the use of sophisticated or exotic methodology, the accident causes can be easily communicated to readers with a wide variety of experience and technical expertise.

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(8) Provides a source for the identification of organizational needs and the formulation of recommendations to meet those needs. The charting technique provides the basis for a systematic trace of the logic from a statement of the facts through the analysis, conclusions, judgments of needs, and recommendations.

(9) Provides a method for evaluating the factual basis of possible recommendations.

(10) Finally, the technique has shown to be useful in solving various unanticipated problems associated with preparing the final report for specific accident investigations.

For example, the clear identification of events and condi-tions as factual or presumptive assists in complying with the DOE report format, which requires explicit separation of facts, analysis, and conclusions into separate and distinct report sections. Also, the clear and logical development of the accident events and causal factors facilitates agree-ment among report reviewers on accident causation and mini-mizes negative reaction from those persons and organizations whose performance deficiencies contributed to accident occurrence. They may not like what the report says, but O

they will agree that it is fair and accurate.

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5.

PRACTICAL APPLICATION How can an investigator best apply E&CF charting to reap the bene-fits outlined in this monograph? The experience of many people partici-pating in numerous accident investigations has led to the identification of seven key elements in the practical application of E&CF charting to achieve high quality accident investigations.

(1) Begin early. As soon as you start to accumulate factual information on events and conditions related to the accident, begin construction of a " working chart" of events and causal factors.

It is often helpful also to rough out a fault tree of the occurrence to establish how the accident could l.

have happened. This can prevent false starts and " wild goose chases" but must be done with caution so that you don't lock yourself into a preconceived scenario of the accident occurrence.

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(2) Use the guidelines suggested in this monograph.

They will assist you in getting started and staying on track as you reconstruct the sequences of events and conditions that influenced accident causation and amelioration.

Remember to keep the proper perspective in applying these guidelines.

They are intended to guide you in simple application of a valuable investigative tool.

They are not hard and fast rules that must be applied without question or reason.

They have grown out of experience and fit well in most applications, but if you have a truly unique situation and feel that you must deviate from the guidelines for clarity and simplicity, do it.

(3) Proceed logically with available data. Events and causal factors usually do not emerge during the investigation in the sequential order in which they occurred.

Initially, there will be many holes and deficiencies in the chart.

Efforts to fill these holes and get accurate tracking of the event sequences and their derivation from contributing conditions will lead to that deeper probing by investigators which will uncover the true facts involved.

In proceeding logically, using available information to direct the search for more, it is usually easiest to use the accident or loss event as the starting point and reconstruct the preaccident and postaccident sequences from that vantage point.

(4) Use an easily updated format. As additional facts are discovered and as analysis of those facts further identify causal factors, the working chart will need to be updated.

Unless a format is selected which displays the emerging information in an easily modified form, construction of the chart can be very repetitious and time-consuming.

Successive redraf ts of the E&CF chart on large sheets of paper have been done; magnetic display boards or chalkboards have been used; but the technique that has consistently proven most effective and most easily updated is use of 3" x 5" index cards on which brief event or condition statements are written. A single event or condition is written on each card. The cards are then taped to a wall or a large roll of heavy paper, or are placed on a large flat surface, in order of the sequence of events as then understood. As more information is revealed, cards can be rearranged, added, or deleted to produce a more complete and accurate version of the working chart. Once the card-based working chart has been finalized, the E&CF chart can be drawn for inclusion in the investigation report.

Several investigators have testified of the value of this approach,

' commenting that it made their investigations more expeditious and thorough. They further stated that use of the index 0

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cards for the working chart not only was useful in esta-blishing the accident sequence and identifying key events and conditions, but it also illuminated deficiencies in knowledge,. pointed out areas for further inquiry, and finally made the report writing relatively straightforward.

Figure 3 shows a typical accident investigation committee employing this approach.

(5) Correlate use of E&CF charting with that of other MORT investigative tools. The optimum benefit from MORT-based investigations can be derived when such powerful tools as the E&CF charting, MORT chart based analysis, change analysis, and energy trace and barrier analysis are used to provide supportive correlation.

(6) Select the appropriate level of detail and sequence length for the E&CF chart. The accident, itself, and the depth of investigation specified by the appointing authority in his letter of appointment to investigating committee members will often suggest the amount of detail desired.

These, too, may dictate whether ending the E&CF chart at the accident or loss-producing event is adequate, or whether the amelioration phase should be included. The way the amelioration was con-ducted will also influence whether this should be included and in how much depth it should be discussed.

Certainly, if second accidents occurred during rescue attempts or emergency action, or if there were other specific or systemic problems revealed, the E&CF chart should cover this phase.

However, the investigators and the appointing authority involved will have to decide, on a case-by-case basis, what is appropriate depth and sequence length on each accident investigated.

(7) Condense the working E&CF chart to make an executive summary chart for the report. The E&CF working chart will contain much detail so it can be of greatest value in shaping and directing the investigation. Normally, significantly less detail is required in the E&CF chart in the investigation report, for its primary purpose is to provide a concise and easy-to-follow orientation to the accident sequence for the report reader. When a detailed E&CF chart is felt to be necessary to show appropriate relationships in the analysis section or an appendix of the report, an executive summary chart of only one or two pages should be prepared and included in the report to meet the above stated purpose.

In summary, the seven key elements in practical application of E&CF charting on accident investigation are:

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h (1) Begin early.

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(2) Use the guidelines.

(3) Proceed logically using available data.

(4) Use an easily updated format.

(5) Correlate with other MORT investigative tools.

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Include appropriate detail and sequence length.

(7) Make a short executive summary chart when necessary.

Finally, the use of E&CF charting has proven to be a valuable tool for accident investigators and a clear and concise aid to understanding of accident causation for the report readers. Use it for greater effec-tiveness in accident investigating and reporting.

6.

REFERENCES

[1] Ludwig Benner, Jr., " Accident Investigations: Multilinear Events Sequencing Methods", Journal of Safety Research, 7_, 2 (1975).

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[2]

W. G. Johnson, MORT - The Management Oversight and Risk Tree, SAN 821-2, February 12, 1973.

[3] Based on Outlines and Charts Developed by Henry Wakefield and Ludwig Benner of the National Transportation Safety Board and Staff Members of the EG&G Idaho, Inc. System Safety Development Center.

[4]

W. G. Johnson, The Accident / Incident Investigation Manual, ERDA-76-20, Prepared for the Division of Operational Safety, Energy Research and Development Administration, August 1,1975.

[5]

W. G. Johnson, " Sequences in Accident Causation", Journal of Safety

Research, 5_, 2 (1973).

[6] Report of the Investigation Board on the X-Ray Exposure at the Pantex Plant, Albuquerque Operations Office (September 27,1974).

[7] Raymond L. Kuhlman, Professional Accident Investigation - Investigative Methods and Techniques, Institute Press,1977.

[8] Report of the Investigation Board on the Accident at Drill Hole U2EC Peninsula, Area 2, Nevada Test Site, Nevada Operations Office (October 23,1975).

[9] Report of Investigation of Near-Fatal Accident at the Central Facilities

. O Vehicle Maintenance and Repair Shop, Idaho National Engineering Laboratory,

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EG&G Idaho, Inc. (April 25,1977).

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LOX TANK EXPLOSION [4]

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GRINDING WHEEL DISINTEGRATION N0 LiffTRUCK'St0 LIFT TRUCK (CLAMATION [ J MFLCitNT OPERATIONS IR fxAM d0 R PROGRAM AND COND gp SE TO AR [ M:SUSE Of PROGRAM STANDARDS tiri TRUCK MACHINE SHOP TRUCm DAMAGE y f RL M PROG DEFICIENT ENGINEERWG [ ~ PRO l RES O WORytD ON LARGE TOOL in PROGRAM AND / SMAll WHEEL 1' [ RADIAi@ WH(El PROGRAM STANCARDS / FRAGMENT STRUCm TRLsCP PUNCTUR! CONTACT CONIALI 'I nRONG SPIED GRtN0tNG E IN C l HIGH SPEED ISSEC NST LLE Dis NTfCRATED CONTACT PARTS Blh l STRUCK '-[ f WHE[L FRACMENT dL DE LOSS j, OPtRATOR'S Df ii n INADEQUATE EYE SH;ILD DE SHIELD I DEFICllNT MAINTINANCE DIRTY. SCARRf D. PLATE REMOVID NO INSPECTION HINGE RUST [0 FROM GRINDER PROGRAM fiRST AID GIVEN iL NO SUPlRVISOR DEflCIENT DE PROTECit0N DtLAYED SEL T N& W G NI 108 TRAlMNG WI USID 100 ANALYSIS PROGRAM g q ji JL N N0 EMERGENCY TO

RESPONSE

Q DEFICIENT HISTORY Of h / Snbggyr 42% ~ PERSONAL

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APPENDIX F (cont.) gg hhk B. Grmding e M b uard eye seld / v Outline e

1. Wheel guard not en proper pos,t.on A Conta t teetween gemdmq wheet anrf mower blade resulted en wheel a No tongue over uppet memng.

b Guard not movable to contros upper o;,en.nq 1 Gond ng wheel accelerated ta high speed Inst *quate purchasing standards a New wheel not cun in a ter installation. No safety a, proval of purchase s leistalletf by operator riol f ametter wath ruft en procedure l In#! equate program Stand 4eds did not prohibe change of wheels by other than c _ Guard turned past 65" poset on ma.nnnance penple op,,,,,, no,,,,,e of guard pos tson standards. ftun en proceduee nos oubbshed Mamtenance not aware of guard position standards l Task analysis not performert ] Instequate comphance with ANSI B F 1 l Defic.ent superv sor teammg program l Inadequate program 2 Eye shiesd removers from grinder. f* E acessswery worn wheet not detected by inspention a Eye sheeld dirty and greasy Not erfentiteed as criteral pa,e

b. E ve sh* eld heavily scratchers No enumtron schertute est hhshed c E ye shoeid henge rusted and froren l Supervasor not tramed on pianned mspect.on program inadmuare mamtenance scherfuse l Lack of peogram st.endards In*.leWafe spervssor Mtson Gonder spendte speed had been encreased to maintain wheeg sue f ace speed as wheel wore down l Inar$ equate progesn C. Gondme wheel fragreent struck operator's eye.

Opesator not aware of speed artiustment peru edure

1. Opwam not using personal eye prowction.

Debcient operator t-aming progeam a Protective goggies hangmg near grinder. l Inadequate sesection and placement program

b. Protective goggles derty and actatched Deficient tob onentation on transfer.

l Inadequate selection and pixement progsarn inadequate workes attron to mamta n goggles. l LMk of stanrfard Deficeent lob analysis a d traening In*1 equate supervisor action on care of eaurpment Inadequate supervator selection n I D'04#8'"- l Inadequate supervisor selection and trameng. Wheel replar.ernent proceduee not pubbshed l lnadequate program. l Not ersentif.ed as critical rat

c. Opcestor had history of daregard for use of personal protect.we t

~+~a' I inader,u,e moge, W O' "' N *'"UY ODwed opaeaw wwithout eye protecteon Tool room assued wheet to opeestor yr WO' " d'd "O' PO 0'0" O' 8"d85 'O Supw '50' [ h Standards did not d.tferentiate between pets to be issued { to maintpance and tools and parts which Could be Def ectent comphance progeam \\ sisued to equipment opef ators inadequate framing %J l Inadequate program inadentuate progsam b Lrme speed gemdmq wheel enstalled on high speed geevider Dehcient sups vasory sob obterwatson. Low speed wheels mened with high speed wheels en parts bens ( Inadequate supe esor selecteon and traineng l laadmuste program Stock shiftert m eeorganeration

2. No f erst and artmmestered af ter infury.

Res rns to stark not reparkaged to show identification u 4. Supervisor and work sect on peuple not trasned m first aid. l lerk of steridard for markmq refuen of assued paris l leadequate program No matkeng op edentification of wheel type in ury aggravated by failure to flush foreegn material from b s Low speed and high speerf wheels have same gpictdie snie eye Purchase not Contdes*ated with safety r$epiirtyrient a b con sa n foHowmg me accident l t er k of program standards for purcr.ns.no intenteonel Condition to permet use of sacess high speed b No errtergevy Eteorg training of rnanagers and supervssors. wheel stoc k, (ark of compteente with ANSI B71 2 Mower blade not supporved by toos rest O C4nd*g wheelI'agment punClured moWmg tractor sediator. a Tool test not reset to 1 B" Clearance wheet neww wheel enstalled L Tracw mowel enm mop area Operator d.d not under* tend emportance of tool rest and wheel guard position la Trerfor mis-used as peesonal transport to shop e inadesguaM traenmg l Supervisor condoned general mas use. No task analysis l Lack of Comphance with standards. No standard pob procedu<e 2 Tractor darnaged m towing f rom shop. No supeevesory key point tvosag wogsam

a. Tow cham weapped around steerme machenesm rods f Inarlequate supervssory training and quahteration

b. Brah e not release t before attempfmq TOWmg Tool rest clearance not choc kerf by supervisor or techmcally inadequase plannmg for control of damaged equipment.

Quableed 6nspectot Inadequate investigation prograrn. inadmu.fe.nspeason progr-Ste.,ng,ods ben,. Supervisor nol tremed on mspection programs. sie,ong rods descarded and repixed. l Inadequate program. l No program for emarrienation and reclamation of Toni rest clearance s,and,d not eniorced m n,,np.ny I arc deai d.tnages Standards enforcement tas m penduct development ( inadequate mvestigar.on pogram. Standard not Contadored sagmtscent en productson area.

c. Tf ansmession damaged by towing tractor backwards af ter

'"*""9 'Od' d'"89"d l Inadequate comphance ! ***** **"*"9 b CO'e d damaged usuemne / h b Holders for targe work not available within piant I 'aad=* mva=taa=== ( ) Beneemt not o.aiwated fo, quahty o, o,ety. v No o,ety evalua,.on of bene,et Io, p,oduaion i.ne. I iandesa program F-2

weighed against the benefits as determined by the severity and frequency potentials. Several types of systems safety analyses will be Systems safety analyses are a variety of qualitative described in this section, along with their general and quantitative methods of imaginatively looking use in accident investigation analysis. To use the at every conceivable way an undesired event could methods, amplified information and instructions occur. The qualitative methods are highly orga-will be needed. A more extensive mtroduction to nized forms of subjective hazard recognition and systems safety can be found in Chapter XVI of anticipation. The quantitative methods apply loss Control.1/anaftement and a detailed explana-known or experimentally determined probable fre-tion in the llandho(>h of System and Product Safe. quency and severity to evaluate the potential for ty. Several other texts are listed in Part IV Itefer-loss. Each part of the system, the people, equip-ences. h ment, material and environment (PEME) is consid-ered for its entire life from design to disposal. 3_ywn,U ) Selection, hiring or purcha.se, training or installa-tion, use and misuse, maintenance and improve-11.7.1. Definitions. ment, transfer and salvage, are all looked at. Proper use, as well as improper use, is evaluated to the The diagrams, models and mathematics which usu. extent of the imagination. Effects within the sys-ally accompany discussions of systems safety are tem and its four elements (PEME), as well as ef-often more discouraging than they are enticing to l fects on outside systems wherever they interface - the safety professional. A mathematical back-influence, control or affect each other - are ground is not really needed to benefit from the looked at to the extent of activities which are knowledge system safety has produced. An aware-planned or in any way conceivable. Time and imag-ness of the different methods and when they might l ination are the only constraints. When any analysis he used can alert the safety professional to situa-technique is considered, the extensiveness of the tions where he might seek help in analysis from a proced ure, and its consequent costs, must be systems safety engineer. O SOCI AL SYSTEMS l POLITIC AL SY ST E M S JU DICI A L / SYSTEMS g OPEg4pONAL O '- NO\\NN pH Abb S lI ,L'$^A %^ '%[, 1 P" p CI p3 0 At g gdt c,0N SA' q jO Ti~l ,--:~~~~~~ l~~~~~ ~""~~~ l l [- 1 OTHEn BUSINESS i SYSTEMS O FIGURE 14 7. The business system,its life span and interfaces with the universe that surrounds it 178

tw.1 a ra ....--. e %e I % M e.gess....ma g.4ys.a bl. se.e. srin.a.. q,. pr. g a.el. APPEtlDIX G PENINSULA ACCIDENT .P L.nra.s., g... 9.t.se.e 1..n. d b i.. s,,. -.. ~,... ......m,,.. .... - ~.. ) Yk sr /G o m e w. a ._....4.s.. ro e,

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/ t Contributory Conditions Sequences (next page) -_.L____ Front Wheel Rear Wheel Stops Not Chocks Installed Not Used i Perfonned Minor Received Order Drove Car Onto Positid Servicing of For front End Alianment Machine~Wheelsj Two Cars Alignment Of ment Pa Without Incident Sedan Ela523 4-25-77 I Shif Took Wife b Both Returned to to Doctor on Ne Work on Monday Thursday p.m. 4-21-77 4-25-77 Wife Became Ill Wife at Work Not Ful1y W Recovered i ( = P00R;0RIGINAl Strong Wheels Managemeni Not Chocked Emphasis Or or Blocked Preventin< Property W Worked Frozen Bolt Car Started Car Rolled Tried to S' on "A" Frame Back Rockin4 Forward Off Rollir.g Ci and Forth with Alignment Machine by Hand [ Large Wrench Left Side Took j of Car Damage No Evasi l by Contact With Action lignment Rail s / T e

\\ 's Set Shift Lever From APPENDIX H Outside Car b93 ALIGNMENT PIT ACCIDENT ( Did Not Get Shift level Into Park tion I h:dFront Placed Shift Lever Checked Front End Adjusted Cambe-On Moved Under Right

• bn Align-ir What He Thought Alianment Both Front Wheels Front of Car to ds by Rtne was Park Positior Adjust Caster on Right Wheel Found t Lever Parking Car Stable Wheels Incorrect t In Brake Not During These Turned to Ca ber and

' tral Set Adjustments The Right u l Some Preoccupation With Wife's l 111 ness i Hend and Chest Pioned Tr ed to Kee) Chest l Expaided to l Protact Head Called for Help me kr h Car rc e and Alignment for hip Pit Ledge Tlecy ifent to fit To Render Aid Front Bumper Fixture Ruptured, Several Shop Struck 689 kPa Releasing Air Workers Heard (103 psi) Under Pressure Escaping Air Compressed Air Fixture le Accid:nt H-1

i l APPENDIX No Shop Plan For Rescue or Amelioration l Foreman Res l Did Not Assume Effor Control At p Coorc Accident Scene g Company No Company g Energency Manua Direction On Provides Direction Control Of Only on Rad.& Disaster-cident Scene Foreman Arrived He Entei Type Emergencies at Alignment Pit Try To l V Ni Gu Pro [ \\ i' R00R.0RIGINAL They Went to Pit Initial Arrivals Tried Unsuccc.5-to Render Aid Entered Left fully to Lift Car Side of Pit i f ON Lef t to Get Truck and Chain To Pull Car Out i 1 Ameli

\\ \\ it(cont.) cue t Not OnatId

d Car To Men In Pit Gave ]K He Moved Gear After Starting, Right Tie Rod ack It Off to Start Engine Shift Leve* to Tried to Back Car Caught Under Neutral Position Off Alignment Front Corner Of to Start Engine Machine Alignment Machine Right Rail

' Company nidentified econ delin2s On Caller Gave Unidentified ierly Placin9 Incomplete Caller Gave .mergency nformation an Incomplete Inf l Calls Hung Up & Hurg U Ambulance Request Ambulance ( ? D a Fr a ment e j .t 1106 4 CaHs Second Call Fire Dept. Phone Received at 1108 Notified Medical D pa e s Dept.of Possible l9 Restraint Caller Situation Understood To Say s Man Had 00"' 0' No Autnmatic Tape Recording of Calls i I l f He Told Others Compressed Air To Call For Supply Valved Off Ambulance and And Compressor Shut Off Shut Down Compr:ssed Air

ration h

\\ H-3

APPENDIX H (coni Foreman Left Pit To Verify That Ambulance Had Been Called h / Mbulance Arrived \\ At Shop Fire Department f rersonnel On Foot l-g Arrived at Shop P Gripped Word Passed Er Sat ~(Er Examined Er Tol ~~ Er 's That He In Corner Of By First-Aid. Fireman Not' Coveralls And Was Free Pit To Rest Trained Fireman Touch Him. Pulled Him Free As He Arose Found No Debilitating I uries 9en Returned With They Moved $ Truck. Chain, and ment So Mba Jack, and Were Could En01 Advised That Er __ l'as Free P Suffered Back Pain During Rescue Amelioration

• )

Foreman Notified Er 's Wife Of Accident and His Condition Attended By Registered Nurse i Fireman Er Arose Er Placed He Was Taken Transported By Ambulance To Bac6ed Off And Walked To On Ambulance to Hospital in Ambulance. Gurney and Moved Dispensary b Accompanied by Into Anbulance B1 ,p Injuries Were Identified and Treated He Didn't roow Er 's Mental State Still Expected Restraint Mt Situation Placed on Short Term Lifting Restriction luip-P and Mi ance H Were Treated For tr Back Injuries At Med. Facilities P Returned To Work With No Restrictions P00R ORIGINAL\\ ~ H-5

a l OTHER SSDC PUBLICATIONS IN THIS SERIES SSDC-1 Occupancy-Use Readiness Manual SSDC-2 Human Factors in Design SSDC-3 A Contractor Guide to Advance Preparation for Accident Investigation SSDC-4 MORT User's Manual SSDC-5 Reported Significant Observation (RS0) Studies SSDC-6 Training as Related to Behavioral Change SSDC-7 ERDA Guide to the Classification of Occupational Injuries and Illnesses l SSDC-8 Standardization Guide for Construction ana Use of MORT-Type Analytic Trees SSDC-9 Safety Information System Guide SSDC-10 Safety Information System Cataloging SSDC-ll Risk Management Guide SSDC-12 Safety Considerations in Evaluation of Maintenance Programs SSDC-13 Management Factors in Accident and l Incident Prevention (Including Management Self-Evaluation Checksheets) I 4 l l .,.}}