Safety

1
Chapter 20

• Safety

2
Goals of Safety

• Reduce errors
• Reduce proportion of errors that become accidents
• Reduce proportion of accidents that become
  injuries
• Reduce lost days/injury

3
Injury and Severity Rate

• Injury rate Injury cases/year
• 200,000
• Actual hours worked/year
• Severity rate Days charged
• Injury cases/year

4
Selection of Problems

• Decision method
• Multiply frequency rate for each type of accident
  by the severity rate.
• Consider refining by including dollar cost/case.
• Rank order annual costs.
• Consider using a Pareto analysis.
• Examine high-energy sources.

5
Management Approach

• Management commitment to safety is the dominant
  factor in success.
• Consider joint management/worker committees.
• Categorize accidents
• Unsafe conditions
• Unsafe acts
• Charge Worker Compensation and medical costs to
  the department.

6
Open Manhole Analogy

• Warning approach Put up signs.
• Guarding approach Install a guard.
• Engineering approach Cover the hole.
• The engineering approach is most effective and is
  permanent.

7
Reduction of Unsafe Conditions

• Reduce equipment failure
• Design the proper control, display, and
  environment
• Use distance
• Use guards
• Use time

8
Reduce Equipment Failure

• Reduce the Failure Rate
• Reduce the number of failure locations.
• Design in safety factors.
• Use redundant equipment (parallel or standby).
• Use preventive maintenance.

9
Reduce Equipment Failure (cont.)

• Reduce Hazard
• Use GFCIs to eliminate electrical hazard.
• Use fail-safe designs (fuses, deadman throttles).
• Use battery power or compressed air instead of
  110V.
• Use smaller amounts of dangerous materials.
• Use radial tires and front-wheel drive.

10
Use Distance as a Protective Technique

• Separate people from equipment.
• Reduce speeds.
• Provide vertical clearance for people and
  vehicles.
• Provide barriers and walls (guards).

11
Use Guards as a Protective Technique

• Use guards that cannot be defeated easily.
• Make guard defeat or failure easily detectable.
• Guards should not present a hazard.
• A poor guard is a hazard.

12
Machine Guards

• Are attached to equipment to prevent people from
  dangerous contact.
• Do not accept guarded by location.
• Consider guards as part of a layered defense.
• Use lockout/tagout procedures.
• Purchase guards from the manufacturer when the
  machine is purchased.
• Guards should not impair machine function.

13
People Guards

• Are protective clothing.
• Problems
• Failure of protective clothing results in injury.
• Workers have incentives not to use protective
  clothing.
• Have a variety of sizes available.
• Impose severe penalties for not using safety
  equipment.
• Organizations should purchase and maintain the
  equipment.

14
Fault Trees

• Use symbols to show how an accident could occur.
• Consider using mathematics to quantify
  probabilities.
• AND gates attenuate probabilities.
• OR gates multiply probabilities.
• Look for single-point failures.

15
Unsafe Acts

• Treat all accidents as unsafe conditions.
• Unsafe acts may result from
• Lack of knowledge
• Deliberate risk
• Drug effects

16
Lack of Knowledge

• Make a fault analysis of all possible failures.
• Consider both operator errors and equipment
  failure.
• Provide a decision structure table in case of a
  problem.
• Communicate this information to people at risk.
• Remember that training is not permanent.

17
Deliberate Risk

• Occurs because risk is low, cost of compliance is
  high, or rewards are large and immediate.
• People modify their behavior to take more risks
  when a device reduces the risk.
• Reinforce safe behavior with positive rewards
  punish unsafe behavior.
• Consider using a safety traffic light.

18
Drug Effects

• Alcohol contributes to a significant number of
  accidents.
• Focus on changing the machine/system rather than
  the individual.

19
Warnings

• Are information about a possible negative
  consequence.
• An effective warning should change behavior.
• May be visual, auditory, or vibratory.
• Need increases when
• Injury potential increases
• Danger is less obvious
• Injury onset is not obvious
• More people are exposed

20
Problems with Warnings

• P The information must be Present.
• R The warning must be Read.
• U The reader must Understand the warning.
• M The person must Remember the information.
• A The person must Act on the information.
• E The warning must be Effective (the person
• must be able to perform the desired
• behavior).

21
Medical Management

• Emergency care
• Plant nurse
• First aid training
• Other provisions
• Rehabilitation and return to work

22
Use Time as a Protective Technique

• Limit exposure time to hazardous conditions or
  materials.
• Use GFCIs.
• Provide washing facilities for chemicals.
• Minimize distances to carry hazardous items.