Document Sample

               Chapter 6
   Hazard analysis has proven to be an excellent tool to
    identify and evaluate hazards in the workplace.

   Written analysis often serve as the basis for more
    thorough inspections. Management can request a
    formal, written analysis for each critical operation.
    Such analysis not only gather information for
    immediate use, but they also obtain benefits over the
    long run.

   For instance, once important hazard data are
    committed to a paper, they become part of the
    technical information base of the organization. These
    documents show the employer's concern for locating
    hazards and establishing corrective measures before
    an accident happens.
What Is Hazard Analysis?

   Hazard analysis is an orderly process used to
    acquire specific hazard and failure data relevant to a
    given system. The method forces those conducting
    the analysis to ask the right questions and helps to
    answer them.

   By locating those hazards that are the most
    probable or have the severest consequences,
    hazard analyses provide information needed to
    establish effective control measures.

   Analytic techniques assist the investigator in
    deciding what facts to gather, determining probable
    causes and contributing factors, and arranging
    orderly clear results.
What are some uses for hazard
   It can uncover hazards that have been unnoticed in the
    original design, or setup of a particular process, operation,
    or task.
   It can locate hazards that developed after a particular
    process, operation, or task was instituted.
   It can determine the essential factors and requirements for
    specific job processes, operations, and tasks. It can
    indicate what qualifications are prerequisites to safe and
    productive work performance.
   It can indicate the need for modifying processes, practices,
    operations, and tasks.
   It can identify situational hazards in facilities, equipment,
    tools, materials, and operational events (for example,
    unsafe conditions).
   It can identify ergonomic situations through work
    design (for example, work-table heights, chairs,
    reaching capabilities).
   It can identify work practices responsible for accident
    situations (for example, deviations from standard
   It can identify exposure factors that contribute to
    injury and illness (such as contact with hazardous
    substances, materials).
   It can identify physical factors that contribute to
    accident situations (noise, vibration, insufficient
   It can determine appropriate monitoring methods and
    maintenance standards needed for safety.
   It can determine the possible results of failures/
    accidents, the persons or property exposed to loss,
    and the potential severity of injury or loss.
Choosing a Method
   To decide what hazard analytical approach is best for a
    given situation, the hazard control specialist will answer
    five questions:

    1. What is the quantity and quality of information desired?
    2. What information already is available?
    3. What is the cost of setting up and conducting
    4. How much time is available before decisions must be
       made and action taken?
    5. How many people are available to assist in the hazard
       analysis, and what are their qualifications?
Who Should Participate in Hazard
   A hazard analysis, to be fully effective and reliable,
    should represent as many different viewpoints as
    possible. Each person familiar with a process or
    operation has acquired insights concerning
    problems, faults, and situations that can cause

   These insights need to be recorded, along with
    those of the person initiating the hazard analysis
    usually the safety professional. Input from workers
    and employee representatives can be extremely
    valuable at this stage.
What Factors Need to Be

   All machines, equipment, processes, operations,
    and tasks in any establishment or facility are good
    candidates for hazard analysis because they have
    the potential to cause accidents.
   Eventually, hazard analysis should be completed for
    all jobs, but the most potentially threatening should
    have immediate attention.
   In determining which processes, operations, and
    tasks receive priority, those making the decisions
    should take the following factors into consideration:
   Frequency of Accidents. Any operation or task with
    an associated history of repeated accidents is a good
    candidate for analysis, especially if different employees
    have the same kind of accident while performing the same
    operation or task.

   Potential for Injury. Some processes and operations can
    have a low accident frequency but a high potential for
    major injury (for example, tasks on a grinder conducted
    without a tool rest or guard).

   Severity of Injury. A particular process, operation, or task
    can have a history of serious injuries and be a worthy
    candidate for analysis, even if the frequency of such
    injuries is low.
New or Altered Equipment,
Processes, and Operations
   As a general rule, whenever a new process, operation, or
    task is created or an old one altered (because of
    machinery, equipment, or other changes), the safety
    professional or supervisor should conduct a hazard
   For maximum benefit, the hazard analysis should be done
    while the process or operation is in the planning stages.
    No equipment should be put into regular operation until the
    safety professional has checked it for hazards, studied its
    operation, installed any necessary additional safeguards,
    and developed safety instructions or procedures.
   Sticking to such a procedure ensures that managers can
    train employees in hazard-controlled, safe operations and
    help to prevent serious injuries and exposures.
Excessive Material Waste or
Damage to Equipment

   Processes or operations producing excessive
    material waste or damage to tools and equipment
    are candidates for hazard analysis. The same
    problems causing waste or damage could also,
    given the right situation, cause injuries.

   One of the first steps in hazard and accident
    analysis is performing job safety analyses. It can be
    specifically tailored to individual jobs or categories of
    jobs in the workplace.

   Job safety analysis (JSA) is a procedure used
    to review job methods and uncover hazards
      1. may have been unnoticed in the layout of
         the facility or building and in the design of
         the machinery, equipment, tools,
         workstations, and processes;
      2. may have developed after production
      3. resulted from changes in work procedures
         or personnel.
Benefits of JSA
The principal benefits of a JSA include:

  1.   giving individual training in safe, efficient procedures
  2.   making employee safety contracts
  3.   instructing the new person on the job
  4.   preparing for planned safety observations
  5.   giving pre-job instruction on irregular jobs
  6.   reviewing job procedures after accidents occur
  7.   studying jobs for possible improvement in job

A JSA can be done in three basic steps. However, before
  initiating this analysis, management must first carefully
  select the job to be analyzed.
    Selecting the Job
   A job is a sequence of separate steps or activities that
    together accomplish a work goal. Selection of jobs to be
    analyzed and establishment of the order of analysis should
    be guided by the following factors:

    Frequency of Accidents. The greater the number of
      accidents associated with the job, the greater its priority
      claim for a JSA.
    Rate of Disabling Injuries. Every job that has had disabling
      injuries should be given a JSA, particularly if the injuries
      prove that prior preventive action was not successful.
    Severity Potential. Some jobs may not have a history of
      accidents but may have the potential for producing severe
    New Jobs. Changes in equipment or in processes obviously
      have no history of accidents, but their accident potential
      may not be fully appreciated. A JSA of every new job
      should be made as soon as the job has been created.
      Analysis should not be delayed until accidents or near-
      misses occur.
After the job has been selected, the three basic steps
in making a JSA are:

  1. Break the job down into successive steps or activities
     and observe how these actions are performed.
  2. Identify the hazards and potential accidents. This is the
     critical step because only an identified problem can be
  3. Develop safe job procedures to eliminate the hazards
     and prevent the potential accidents.

Breaking the Job Down into Steps

  Before the search for hazards begins, a job should be
  broken down into a sequence of steps, each describing
  what is being done.
Identifying Hazards and Potential
Accident Causes
   The purpose is to identify all hazards-both those
    produced by the environment and those connected with
    the job procedure.
   Each step, and the entire job, must be made safer and
    more efficient. Ask these questions about each step:
         Is there a danger of striking against, being struck by, or
          otherwise making harmful contact with an object? Can the
          employee be caught in, by, or between objects?
         Is there a potential for a slip or trip? Can the employee fall on
          the same level or to another?
         Can strain be caused by pushing, pulling, lifting, bending, or
         Is the environment hazardous to safety or health? For
          example, are there concentrations of toxic gas, vapor, mist,
          dust, heat, or radiation?
    Identifying Hazards and Potential
    Accident Causes……………
The job observation should be repeated as often as necessary until all hazards
  and potential causes for accident or injury have been identified.

   When inspecting a particular machine or operation, ask the question, "Can
    an accident occur here?" More specific questions include:
   Is it possible for a person to come in contact with any moving piece of
    machine equipment?
   Is it possible to be drawn into the in running nip point between two moving
    parts, such as a belt, chain, pressure rolls, rack and gear?
   Do machines or equipment have respond movement or any motion where
    workers can be caught on or between a moving part and a fixed object?
   Is it possible for a worker's hands or arms to make contact with moving
    parts at the point of operation where milling, shaping, punching, shearing,
    bending, grinding, or other work is being done?
   Is it possible for material (including chips or dust) to be kicked back or
    ejected from the point of operation, injuring someone nearby?
   Are machine controls safeguarded to prevent unintended operation?
   Are machine controls located to provide immediate access in the event of
    an emergency?
   Do machines vibrate, move, or walk while in operation?
Identifying Hazards and Potential
Accident Causes…………..
   Is it possible for parts to become loose during operation,
    injuring operators or others?
   Is it possible for workers to bypass the guard, thereby
    making it ineffective?
   Is there sufficient room for maintenance and repair?
   Are the materials handling methods adequate for the
    work in process and the tooling associated with it?
   Is the work area well illuminated with specific point-of-
    operation lighting where necessary?
   Is ventilation adequate, particularly for those operations
    that create dusts, mists, vapors, and gases?
   Is the operator using personal protective equipment?
   Is housekeeping satisfactory with no tripping hazards or
    spills on the floor?
   Are energy sources controlled for maintenance?
Identifying Hazards and Potential
Accident Causes…………..
   All of these questions will be of most value if they are
    incorporated into an inspection form that can be filled out
    at regular intervals.

   Even though a question may not at first seem to apply to
    a specific operation, on closer inspection it may be found
    to apply. Using a checklist is a good way to make sure
    nothing is overlooked.

   Again, check with the observed employee after the
    hazards and potential causes of accidents have been
    recorded. The experienced employee will probably offer
    additional suggestions. You should also check with
    others experienced with the job.
Developing Solutions
   The final step in a JSA is to develop a recommended safe job
    procedure to prevent the occurrence of accidents. The principal
    solutions are as follows:

       1.   Find a new way to do the job.
       2.   Change the physical conditions that create the hazards.
       3.   Change the work procedure.

   To find an entirely new way to do a job, determine the work goal of the
    job, and then analyze the various ways of reaching this goal to see
    which way is safest.
   If a new way cannot be found, then ask this question about each
    hazard and potential accident cause listed "What change in physical
    condition (such as change in tools, materials, equipment, layout, or
    location) will eliminate the hazard or prevent the accident?"

To investigate changes in the job procedure, ask the following questions
   about each hazard and potential accident cause listed:
 "What should the employee do or not do – to eliminate this particular
   hazard or prevent this potential accident?" "How should it be done?"
   Because of his experience, in most cases the supervisor can answer
   these questions.
   Inspection should be conducted in an organization to locate and
    report existing and potential unsafe conditions or activities that, if left
    uncontrolled, have the capacity to cause accidents in the workplace.

Philosophy behind Inspection
  Inspection can be viewed negatively or positively as either:

    1.   fault-finding, with the emphasis on criticism
    2.   fact-finding, with the emphasis on locating hazards that can
         harmfully affect safety and health

Purpose of Inspection
  The primary purpose of inspection is to detect potential hazards so
   they can be corrected before an accident occurs.
  Inspection can determine conditions that need to be corrected or
   improved to bring operations up to acceptable standards, both from
   safety and operational standpoints.
  Secondary purposes are to improve operations and thus to increase
   efficiency, effectiveness, and profitability
Types of Inspection
   Inspection can be classified as one of two types - continuous or
    interval inspection.

Continuous Inspection
 This process is conducted by employees, supervisors, and
  maintenance personnel as part of their job responsibilities.
 Continuous inspection involves noting an apparently or potentially
  hazardous condition or unsafe procedure and either correcting it
  immediately or making a report to initiate corrective action. Continuous
  inspection of personal protective equipment is especially important.
 This type of inspection is sometimes called informal because it does not
  match to a set schedule, plan, or checklist. The truth is that both
  continuous and interval inspections are necessary and complement one
 As part of their job, supervisors make sure that tools, machines, and
  equipment are properly maintained and safe to use and that safety
  precautions are being observed.
 Tool room employees regularly inspect all hand tools to be sure that
  they are in safe condition. Foremen are often responsible for
  continuously monitoring the workplace and seeing that equipment is
  safe and that employees are observing safe practices. When foremen
  or supervisors inspect machines at the beginning of a shift, a safety
  inspection must be part of the operation
Interval Inspections

   Planned inspections at specific intervals are what most
    people regard as "real" safety and health inspections. They
    are purposeful, thorough, and systematic procedures that
    permit examination of specific items or conditions.

   They follow an established procedure and use checklists for
    routine items. These inspections can be any one of three
    types: periodic, intermittent, and general.

   Periodic inspection includes those inspections scheduled at
    regular intervals. They can target the entire facility, a specific
    area, a specific operation, or a specific type of equipment.

   Management can plan these inspections weekly, monthly,
    semiannually, annually, or at other suitable intervals.
Periodic inspections can be of several different types:

   Inspections by the safety professional, industrial hygienist, and
    joint safety and health committees.
   Inspections for preventing accidents and damage or breakdowns
    (checking mechanical functioning, lubricating) performed by
    electricians, mechanics, and maintenance personnel.
   Inspections by specially trained certified or licensed inspectors,
    often from outside the organization (for example, inspection of
    boilers, elevators, cranes, power presses, fire extinguishing
   Inspections done by outside investigators or government
    inspectors to determine compliance with government regulations.

The advantage of periodic inspection is that it covers a specific
area and allows detection of unsafe conditions in time to provide
effective countermeasures.
Intermittent inspections are those made at
irregular intervals.

   Sometimes the need for an inspection is indicated by
    accident tabulations and analysis. If a particular department
    or location shows an unusual number of accidents or if
    certain types of injuries occur with greater frequency, the
    supervisor or manager should call for an inspection.

   When construction or remodeling is going on within or
    around a facility, an unscheduled inspection may be
    needed to find and correct unsafe conditions before an
    accident occurs.

   The same is true when a department installs new
    equipment, institutes new processes, or modifies old ones.
An effective safety and health inspection program requires the
  1. sound knowledge of the facility
  2. knowledge of relevant standards, regulations, and codes
  3. systematic inspection steps
  4. a method of reporting, evaluating, and using the data.

   An effective program begins with analysis and planning. If
    inspections are casual, superficial, and careless, the results will
    reflect the method.

   Before instituting an inspection program, these five questions
    should be answered:

    1.   What items need to be inspected?
    2.   What aspects of each item need to be examined?
    3.   What conditions need to be inspected?
    4.   How often must items be inspected?
    5.   Who will conduct the inspection?
Hazard Control Inspection Inventory

   To determine what factors affect the inspection, a
    hazard control inspection inventory can be conducted.

   Management should divide the entire facility yards,
    buildings, equipment, machinery, vehicles into areas of
    responsibility. These areas, once determined, should
    be listed in an orderly fashion.

   The analyst might develop a color coded map or floor
    plan of the facility. Large areas or departments can be
    divided into smaller areas and assigned to each first
    line supervisor and/or the hazard control department's
What Items Need to Be Inspected?

Once specific areas of responsibility have been determined,
  managers should develop an inventory of those items that may
  become unsafe or cause accidents. These would include:
 environmental factors (illumination, dust, fumes, gases, mists,
  vapors, noise, vibration, heat, radiation sources)
 hazardous supplies and materials (explosives, flammables,
  acids, toxic or nuclear materials or by-products)
 production and related equipment (mills, shapers, presses,
  borers, lathes)
 power source equipment (steam and gas engines, electrical
 electrical equipment (switches, fuses, breakers, outlets, cables,
  extension and fixture cords, grounds, connectors, connections)
 hand tools (wrenches, screwdrivers, hammers, power tools)
 personal protective equipment (hard hats, safety glasses, safety
  shoes, respirators, hearing protection, gloves, etc.)
 showers, eyewash fountains, first aid supplies, stretchers)
 working surfaces (ladders, scaffolds, catwalks, platforms)
What Items Need to Be Inspected?........
   fire protection and emergency response equipment (alarms, water tanks,
    sprinklers, standpipes, extinguishers, hydrants, hoses, self-contained
    breathing apparatus, toxic cleanup, automatic valves, horns, phones,
   walkways and roadways (ramps, docks, sidewalks, walkways, aisles,
    vehicle ways, escape routes) elevators, electric stairways, and man lifts
    (controls, wire ropes, safety devices)
   material handling equipment (cranes, conveyors, hoists, forklifts, chains,
    ropes, slings)
   transportation equipment (automobiles, railroad cars, trucks, front-end
    loaders, helicopters, motorized carts)
   warning and signaling devices (sirens, crossing and blinker lights,
    klaxons, warning signs, exit signs)
   containers (scrap bins, barrels, drums, gas cylinders, solvent cans)
   storage facilities and areas both indoor and outdoor (bins, racks, lockers,
    cabinets, shelves, tanks, closets)
   structural openings (windows, doors, stairways, sumps, shafts, pits, floor
   buildings and structures (floors, roofs, walls, fencing)
   miscellaneous - any items that do not fit in preceding categories.
What Aspects of Each Item Need to Be Examined?

   Particular attention should be paid to the parts of an item most
    likely to become a serious hazard to health and safety. These
    parts often develop problems because of stress, wear, impact,
    vibration, heat, corrosion, chemical reaction, and misuse.
   Such items as safety devices, guards, controls, work or wear
    point components, electrical and mechanical components,
    and fire hazards tend to become unsafe first.
   For a particular machine, critical parts would include the point
    of operation, moving parts, and accessories (flywheels, gears,
    shafts, pulleys, belts, couplings, chains, controls, lighting,
    brakes, exhaust systems).
   Also to be checked are items related to feeding, oiling,
    adjusting, maintenance, grounding, attaching, work space,
    and location.
What Conditions Need to Be Inspected?

   The unsafe conditions for each part to be inspected should be
    described specifically and clearly.
   Inspectors should describe and not simply list unsafe conditions for
    each item. Usually, conditions to look for can be indicated by such
    words as "uneven, exposed, broken, worn, leaking, rusted,
    corroded, missing, vibrating, loose,".
   Checklists serve as reminders of what to look for and as records of
    what has been covered. They can be used to structure and guide
    inspections. Good checklists also help in follow-up work to make
    sure hazards have been corrected or eliminated.
   Checklists can be prepared by the safety and health committee, by
    the safety director, or by a subcommittee that includes engineers,
    supervisors, employees, and maintenance personnel.
   Choosing the inspection route means inspecting an area completely
    and thoroughly while avoiding:
         1.   time-consuming backtracking and repetitions
         2.   long walks between items
         3.   unnecessary interruptions of the production process
         4.   interruption of employees.
How Often Must Items Be Inspected?
   The frequency of inspection is determined by four factors.

What is the loss severity potential of the problem? The inspector should
  ask, "If the item or critical part should fail, what injury, damage, or work
  interruption would result?" The more severe the loss potential, the more
  often the item should be inspected.
What is the potential for injury to employees? If the item or critical part
  should fail, how many employees would be endangered and how
  frequently? The greater the probability for injury to employees, the more
  often the item should be inspected.
How quickly can the item or part become unsafe? The answer to this
  question depends on the nature of the part and the conditions to which it
  is subjected. Equipment and tools used frequently can become damaged,
  defective, or worn more quickly than those rarely used.
What is the past history of failures? What were the results of these
  failures? Maintenance and production records and accident investigation
  reports can provide valuable information about how frequently items have
  failed and the results in terms of injuries, damage, delays, and
  shutdowns. The more often an item has failed in the past and the greater
  the consequences, the more it needs to be inspected.
Who Will Conduct the Inspection?

   No individual or group should have exclusive responsibility for all
    inspections. Employees who perform these inspections will benefit from
    training in hazard recognition. Some items will need to be inspected by
    more than one person.
   For example, while an area supervisor may inspect an overhead crane
    weekly and maintenance personnel inspect it monthly, the operator of the
    crane will inspect it before each use.
   When grinding wheels are received, they are inspected by the stockroom
    attendant, but they must be inspected again by the operator before each
   As part of the hazard control inspection inventory, management should
    assign responsibility for each inspection.
   A suggested guide for planned inspections is as follows:

          Daily-area supervisor and maintenance personnel, who also can request
           suggestions from employees in their various workstations
          Weekly-department heads
          Monthly-supervisors, department heads, the safety department, and safety
           and health committees.

   The safety department also may be actively involved in monthly,
    quarterly, semiannual, and annual inspections.
Five qualifications of a good inspector are:

    1.   knowledge of the organization's accident experience
    2.   familiarity with accident potentials and with the standards that
         apply to his area
    3.   ability to make intelligent decisions for corrective action
    4.   diplomacy in handling personnel and situations
    5.   knowledge of the organization's operations-its workflow, systems,
         and products.

Safety Professionals

   The number of safety professionals depends on the size of the
    company and the nature of its operation. Large companies with
    well-organized accident prevention programs usually employ a
    full-time staff.
   In organizations where toxic and corrosive substances are
    present, the industrial hygienist will be part of the inspection
Company or Facility Management
   Safety inspections should be considered part of the duties of
    company or facility management. By participating in inspections,
    management demonstrates its commitment to maintain a safe
    working environment.

First-line Supervisor or Foreman

   Because supervisors and foremen spend practically all their time in
    the shop or facility, they continuously monitor the workplace. At least
    once a day, supervisors need to check their areas to see that

       1.   employees are complying with safety regulations,
       2.   guards and warning signs are in place,
       3.   tools and machinery are in a safe condition,
       4.   aisles and passageways are clear and proper clearances maintained,
       5.   material in process is properly stacked or stored.
 Before beginning the workday, the employee should inspect the
  workplace and any tools, equipment, and machinery that will be used.
 Any defects the employee is not authorized to correct should be
  reported immediately to the supervisor. Action resulting from this
  report must be reported to the employee to encourage further

Maintenance Personnel
 Maintenance employees can be of great help in locating and
  correcting hazards. As they work, they can conduct informal
  inspections and report hazards to the supervisor, who in turn should
  encourage the mechanics to offer suggestions.

Other Inspection Teams
 Management should assign an inspection team that includes the
   hazard control specialist, production manager, supervisor; employee
   representative, fire prevention specialist, and industrial hygienist.
 Outside inspectors sometimes are needed to perform inspections.
   For example, insurance company safety engineers and local, state or
   provincial, and federal inspectors may lend their expertise to specific
   Companies must not only conduct regular inspections but carry them
    out in a way that emphasizes the company's commitment to safety.

Preparing to Inspect
 Inspections should be scheduled for times when inspectors will have the best
   opportunity to see operations and work practices without much interruption.
   The inspection route should be planned in advance.
 Before conducting an inspection, the inspector or inspection team should
   review all accidents that have occurred in the area. At this brief meeting, team
   members should discuss where they are going and what they will be looking
 During the inspection, before going into noisy areas, the team will need to
   discuss what they wish to accomplish in order to avoid arm waving, shouting,
   and other unsatisfactory methods of communication.
 In addition to the regular checklist and accident reports, inspectors should
   have copies of the previous inspection report for that particular area.
   Reviewing this report makes it possible to check whether earlier
   recommendations have been followed and reported hazards corrected.
 Those making inspections should wear the protective equipment required in
   the areas they enter: safety glasses and shoes, hard hats, acid-proof goggles,
   protective gloves, respirators, and so forth.
 If inspectors do not have or cannot get special protective equipment, they
   should not go into the area. They must be careful to "practice what they
Inspection Tools
   Inspectors should have the proper tools ready before the
    inspection to make the process more efficient and to gather
    more precise data. Common tools include:
         1.   clipboards
         2.   inspection forms
         3.   pens/pencils
         4.   lockout/tagout supplies
         5.   measuring tape/ruler
         6.   flashlight.

   Depending on the inspection area or type, the following
    equipment may also be useful:
         1.   cameras
         2.   tape recorder
         3.   electrical testing equipment
         4.   sampling devices (air, noise, light, temperature)
         5.   sample containers
         6.   calipers, micrometers, antenna gauges
         7.   special personal protection equipment
         8.   stopwatch.
Relationship of Inspector and Supervisor

   Before inspecting a particular department or area, the inspector
    should contact the department head, supervisor, or other person
    in charge.
   This person may have important information for the inspection,
    particularly if conditions are temporarily altered because of
    construction, maintenance, equipment downtime, employee
    absence, and so forth.
   If the supervisor of the area does not accompany the inspector,
    the supervisor should be consulted before the inspector leaves the

Relationship of Inspector and Employee

   If not company policy or departmental rules prohibit conversation
    with employees, the inspector can ask questions about operations
    taking care, however, not to take over the responsibility of the
Kinds of Measurement and Testing
   Occupational health observation monitors chemical, physical, biological,
    and ergonomic hazards. Four monitoring systems are used: personal,
    environmental, biological, and medical.

Personal Monitoring
  One example of personal monitoring is measuring the air-borne concentrations
   of contaminants. The measurement device is placed as closely as possible to
   the site at which the contaminant enters the human body.
  When the contaminant is noise, the device is placed close to the ear. When a
   toxic substance could be inhaled, the device is placed in the breathing zone.

Environmental Monitoring
  Environmental monitoring measures contaminant concentrations in the
   workroom. The measurement device is placed in the general area adjacent to
   the worker's usual workstation or where it can sample the general room air.

Biological Monitoring
  Biological monitoring measures changes in composition of body fluid, tissues,
   or expired air to detect the level of contaminant absorption.
  For example, blood or urine can be tested to help determine lead exposures.
   Similarly, the phenol in urine sometimes is measured to document benzene
Medical Monitoring
   When medical personnel examine workers to see their physiological
    and psychological response to a contaminant, the process is termed
    medical monitoring.
   Medical monitoring can include health and work histories, physical
    examinations, x-rays, blood and urine tests, pulmonary (involving
    lung) function tests, and vision and hearing tests.
   The aim of such monitoring is to find evidence of exposure early
    enough to identify especially at risk workers and to detect any
    damage before it becomes permanent.
   Biological and medical monitoring provide information after the
    exposure already has occurred. However, such programs also
    include arrangements to treat an identified health problem and to
    take corrective action to prevent further damage.

Measuring for Toxicity
   Measuring for toxicity involves several activities. These include
    determining a substance's capacity for injury or harm, inhalation
    hazards, influence of solubility, threshold limit values, and
    permissible exposure limits.

   The toxicity of a material is not identical with its potential for
    being a health hazard. Toxicity is the capacity of a material to
    produce injury or harm. Hazard is the possibility that exposure to
    a material will cause injury or illness when a specific quantity is
    used under certain conditions.
   The key elements to be considered when evaluating a health
    hazard are:

          amount of material to which the employee is exposed
          total time of the exposure
          toxicity of the substance
          individual weaknesses.

   Not all toxic materials are hazardous. The majority of toxic
    chemicals are safe when packaged in their original shipping
    containers or contained within a closed system.
The toxic action of a substance can be divided into acute
  and chronic effects.

   Acute effects involve short-term (hours or days) high
    concentrations that can cause irritation, illness, or death.
    They can be the result of sudden and severe exposure,
    during which the substance is rapidly absorbed.

   Chronic effects involve continued exposure to a toxic
    substance over an extended time (usually over 90 days).
    When the chemical is absorbed more rapidly than the
    body can eliminate it, the chemical begins to accumulate
    in the body.
Why Accidents Are Investigated
   Accident investigation is especially important to determine direct
    causes, uncover contributing accident causes, prevent similar
    accidents from occurring, document facts, provide information on
    costs, and promote safety.
   Accident investigation concentrates on gathering all information about
    the factors leading to the accident.

Determine Direct Causes
   Accident investigation determines the direct and contributing causes
    of accidents. At what points did the hazard control system break
    down? Were rules and regulations violated? Did defective machinery
    or factors in the work environment contribute to the accident? Poor
    machinery layout, for example, or the very design of a job process,
    operation, or task can contribute to an undesirable situation.
Uncover Contributing Accident Causes

   Thorough accident investigation is very likely to uncover problems that
    indirectly contributed to the accident. Such information benefits
    accident reduction efforts. For example, a worker slips on spilled oil
    and is injured.
   The oil spill is the direct cause of the accident, but a thorough
    investigation might reveal other contributing factors: poor
    housekeeping, failure to follow maintenance schedule, insufficient
    supervision, or faulty equipment (such as a lathe leaking oil).

Prevent Similar Accidents

   Accident investigation identifies what actions and improvements will
    prevent similar accidents from occurring in the future.

Document Facts

   Accident investigation documents the facts involved in an incident for
    use in any compensation and court case that may arise. The report
    produced at the conclusion of an investigation, becomes the
    permanent record of facts about an accident.
Provide Information on Costs
   Accident investigation provides information on both direct and
    indirect costs of accidents.

Promote Safety
   Accident investigation yields psychological as well as material
    benefits. The investigation demonstrates the organization's
    interest in worker safety and health.
   It indicates management's sense of accountability for accident
    prevention and its commitment to a safe work environment.
   Conducting an accident investigation is not simple. It can be
    difficult to look beyond the incident at hand to uncover causal
    factors, determine the true loss associated with the occurrence,
    and develop practical recommendations to prevent recurrence.
   A major weakness of many accident investigations is the failure to
    establish and consider all factors - human, situational, and
    environmental - that contributed to the accident.
Reasons for this failure include:

     inexperienced or uninformed investigator
     reluctance of the investigator to accept full responsibility for the job
     narrow interpretation of environmental factors
     mistaken emphasis on a single cause
     judging the effect of the accident to be the cause
     arriving at conclusions before all factors are considered
     poor interviewing techniques
     delay in investigating accidents.

  When to Investigate Accidents

     The longer the delay in examining the accident scene and
      interviewing the victim(s) and witnesses, the greater the possibility
      of obtaining incorrect or incomplete information.
     As a general rule, all accidents, no matter how minor, are
      candidates for thorough investigation. Many accidents occurring in
      an organization are considered minor because their consequences
      are not serious.
Who Should Conduct the Investigation?
 A physician's assistance is particularly important when human factors
  have been designated as direct or contributing causes of an accident.
 The physician can assess the nature and degree of injury and assist in
  determining the source and nature of the forces that imposed the injury.
 The physician also can evaluate the effectiveness of measures aimed
  at early detection of medical conditions, mental changes, or emotional

 Management and department heads should help investigate accidents
  resulting in lost workdays or major property damage.
 When management actively participates in accident investigation, it can
  evaluate the hazard control system and determine whether outside
  assistance is desired or required to upgrade existing structures and
 Management also must review accident reports in order to make
  informed decisions. When accident investigation reveals the need or
  desirability of specific corrective actions, management must determine
  whether the recommended action has been implemented.
Safety During the Investigation
   In many cases the accident scene is a dangerous place. The
    accident may have damaged electrical equipment, weakened
    structural supports, and released radioactive or toxic materials.
   The safety and health professional must be particularly alert to
    the hazards encountered by the investigating team and, when
    necessary, see that proper protective equipment is provided.

What to Investigate
   The accident investigation must answer many questions. Because of
    the infinite number of accident producing situations, contributing
    factors, and causes, it is impossible to list all the questions that apply
    to all investigations.
   The following questions are generally applicable, however, and will
    be considered in most accident investigations.

       What was the injured person doing at the time of the accident?
        Performing an assigned task? Maintenance? Assisting another
       Was the injured employee working on an unauthorized task? Was
        the employee qualified to perform the task and familiar with the
        process, equipment, and machinery?
       What were other workers doing at the time of the accident?
   Was the proper equipment being used for the task at hand
    (screwdriver instead of can opener to open a paint can, file instead
    of grinder to remove burr on a bolt after it was cut)?
   Was the injured person following approved procedures?
   Is the process, operation, or task new to the area? Was the injured
    person being supervised? What was the proximity and adequacy of
   Did the injured employee receive hazard recognition training prior to
    the accident?
   What was the location of the accident? What was the physical
    condition of the area when the accident occurred?
   What immediate or temporary actions could have prevented the
    accident or minimized its effect?
   What long-term or permanent action could have prevented the
    accident or minimized its effect?
   Had corrective action been recommended in the past but not

During the course of the investigation, the above questions should be
  answered to the satisfaction of the investigators.
Conducting Interviews

   Interviewing accident or injury victims and witnesses can be a
    difficult assignment if not properly handled. The individual being
    interviewed often is fearful and reluctant to provide the
    interviewer with accurate facts about the accident.

   The accident victim may be hesitant to talk for any number of
    reasons. A witness may not want to provide information that
    might involve friends, fellow workers, or the supervisor.

   To obtain the necessary facts during an interview, the interviewer
    must first eliminate or reduce an employee's fear and anxiety by
    establishing good relationship with the individual. The interviewer
    must create a feeling of trust and establish open communication
    before beginning the actual interview.
Once good relationship has been developed, the interviewer
can follow this five-step method.

1.   Discuss the purpose of the investigation and the interview (fact-
     finding, not fault-finding).
2.   Have the individual relate his version of the accident with minimal
     interruptions. If the individual being interviewed is the one who was
     injured, ask what was being done, where and how it was being done,
     and what happened. If practical, have the injured person or
     eyewitness explain the sequence of events that occurred at the time
     of the accident. Being at the scene of the accident makes it easier to
     relate facts that might otherwise be difficult to explain.
3.   Ask questions to clarify or fill in any gaps.
4.   The interviewer should then repeat the facts of the accident to the
     injured person or eyewitness. Through this review process, there will
     be plenty opportunity to correct any misunderstanding that may have
     occurred and clarify if necessary, any of the details of the accident.
5.   Discuss methods of preventing repetition. Ask the individual for
     suggestions aimed at eliminating or reducing the impact of the
     hazards that caused the accident. By asking the individual for ideas
     and discussing them, the interviewer will show sincerity and place
     emphasis on the fact-finding purpose of the investigation, as it was
     explained at the beginning of the interview.
Preparing the Accident Investigation Report
   An accident in any organization is of significant interest to employees, who
    will ask questions that reflect their concerns. Is there any potential danger
    to those in the immediate surrounding area? What caused the accident?
    How many people were injured? How badly?
   Those who investigate accidents should answer these questions truthfully
    and avoid covering up any facts. On the other hand, they must be certain
    they are authorized to release information, and they must be sure of their
   Summaries of very important information on major injury, damage, and loss
    incidents should be distributed to department managers. Such summaries
    should include information on accident causes and recommended action
    for preventing similar incidents.
   Management should maintain incident and statistical report files as dictated
    by company policy.

Implementing Corrective Action

   Whenever management and safety professionals review monthly accident
    reports, they exercise an essential auditing function. They use accident
    reports to make decisions to prevent similar accidents from occurring.