A Case Study of Behavioral Approaches to Controlling Occupational Exposures

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A Case Study of Behavioral Approaches to
Controlling Occupational Exposures

• References
• Behavioral Technology for Reducing Occupational
  Exposures to Styrene
• Hopkins BL, Conard RJ, Dangel RF, Fitch HG, Smith
  MJ, Anger WK
• Effective and Reliable Behavioral Control
  Technology
• Hopkins BL, Conard RJ, Smith MJ

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Styrene C8H8

• Primarily a synthetic chemical, also known as
  vinylbenzene, ethenylbenzene, cinnamene, or
  phenylethylene
• Colorless liquid that evaporates easily and has a
  sweet smell it often contains other chemicals
  that give it a sharp, unpleasant smell
• Dissolves in some liquids, but doesnt dissolve
  easily in water.
• Used to make products such as rubber, plastic,
  insulation, fiberglass, pipes, automobile parts,
  food containers, and carpet backing
• Low levels also occur naturally in a variety of
  foods

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Styrene Health Effects

• Toxic substance contributing to lung disease and
  cancer
• Enters body through inhalation, ingestion, and
  absorption through skin
• gt100 ppm causes eye and nose irritation
• Short-term exposure to high levels can cause
  neurological effects such as depression,
  concentration problems, muscle weakness,
  tiredness, and nausea
• Long-term exposure leads to neurological damage,
  and possibly liver and kidney damage as well
• Federal standard limit 8 hours at 100 ppm, Time
  Weighted Average (OSHA recommends 50 ppm, TWA)

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Styrene in the U.S.

• 7.5 billion pounds produced annually
• gt30,000 workers in 1,000 plants exposed to
  styrene full-time
• gt300,000 come into contact with styrene
  periodically
• Highest exposures fiberglass-reinforced plastics
  manufacturing industry
• For more info on Styrene, visit ATSDR web site

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Ways to Control Human Exposure to Styrene

• Engineering controls provide direct solutions to
  remove the exposure. For example, through
  ventilation, new production processes where the
  hazard has been removed (e.g. automation in
  letter sorting) or new technologies (e.g. to
  reduce vibration)
• Work practice controls such as personal
  protective equipment or modified work practices
  (e.g. rest breaks)
• Administrative controls such as worker rotation
• The second two types of controls require
  behavioral and/or social change

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Behavioral Controls

• Behavioral means for minimizing workers exposure
  through changing behaviors wearing gloves,
  respirators, etc.
• Considered less reliable
• Recommendations often no more than common sense
• Challenge to implement programs that work

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Basic Process for Making Fiberglass-Reinforced
Styrene Plastic Products
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Behavioral Intervention Focused on Two Classes of
Behavior

• Work Practice Behaviors
• Housekeeping Conditions

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Work Practice Behaviors

• Turning on spray booth exhaust fans
• Keeping breathing zones 18in from styrene sources
• Working upwind of airborne styrene sources
• Working in specific areas to take advantage of
  airflow and exhaust ventilation
• Avoiding standing in front of a person using a
  spray gun
• Avoiding spraying towards another worker
• Spraying toward the exhaust ports of the booths
• Spraying so most of the spray hits the mold
• Locating molds to take advantage of airflow

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Housekeeping Conditions

• All spray booth filters in place
• Overspray buildup on booth filters, floors, and
  walls kept low
• Floors covered by disposable material
• Floor and table coverings not torn or soaked
  through with resin
• Resin-soaked debris removed
• Floors and work table tops free of spills
• Spray booth lights operational and visible
• Waste cans available in spray booths

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Housekeeping Conditions (cont)

• Work areas free of empty chemical containers
• Curing parts removed from work areas when work on
  them is completed
• Wheels on mold carriages turn freely
• Resin and gelcoat containers covered
• Spray equipment gauges visible
• Acetone containers closed when not in use
• Spray guns and hoses not leaking
• Work areas free of food and drink

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Behavioral Interventions

• Training
• Modelling
• Testing and Feedback
• Maintenance

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Training

• Videos of behaviors, and meetings to discuss
  behaviors
• Videos familiarized the workers with styrene and
  demonstrated the usefulness of the housekeeping
  conditions and behaviors
• At the end of the meeting, the trainer gave each
  person a test form they would be responsible for
  passing regarding behaviors they can maintain
• On the job modeling of appropriate behaviors,
  including corrective feedback if behavior was
  wrong and positive verbal feedback is behavior
  was correct

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Testing Use of Appropriate Behaviors

• From 2 days to 1 week after watching a videotape,
  workers were given
• 25 for passing a test on housekeeping
• 25 for passing a test on behaviors that took
  advantage of the airflow of the plant
• 5 for passing each test on keeping breathing
  zones from sources of styrene keeping styrene
  off the skin, avoiding a position in front of a
  spraygun, not spraying towards another person,
  and spraying so that most of the spray hits the
  mold (totals 25)

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Behavior Maintenance

• Trainer conducted tests daily following
  completion of the training, paying 5 for passing
  all the maintenance tests for work behaviors and
  5 for passing all the housekeeping tests
• Verbal praise of appropriate behaviors and
  corrective feedback

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Experimental Design
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Data Collected

• Observations of behaviors used
• Measurement of exposure to styrene
• Measurement of production accommplished (lbs.
  of gelcoat and resin used / number of minutes
  worked)
• Amount of time spent working

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ResultsBehavioral Change

• Work Behaviors baseline levels ranged from 49
  to 76 compliance, but increased rapidly with the
  beginning of training, approaching 100 soon
  after training completion
• Housekeeping Conditions baseline levels varied
  considerably, but were becoming worse, however
  conditions improved rapidly with the beginning of
  training to over 90 compliance at the end of
  training

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ResultsStyrene Exposure

• Significant improvements
• in all three plants

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Results Production and Time Working

• Production Pounds of gelcoat and resin processed
  varied considerably day to day, however means of
  post-training production are close to baseline
  means
• Time Working

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Discussion

• Significant and reliable reductions in exposure
  to toxic substances can be produced by training
  and behavior maintenance procedures
• No undesirable effects on productivity and time
  devoted to work
• Long-term reliability promising, with maintenance
  procedures
• Best protection for employees both good
  engineering and behavioral controls