ERT 312 LECTURE 2 Accident & Loss Statistics. A measure of the effectiveness of the safety programs...
Transcript of ERT 312 LECTURE 2 Accident & Loss Statistics. A measure of the effectiveness of the safety programs...
ERT 312ERT 312LECTURE 2
Accident & Loss Statistics Accident & Loss Statistics
Accident & Loss Statistics Accident & Loss Statistics
A measure of the effectiveness of the safety programs
An indicator whether a process is safe or SOP is working correctly
Taken by average, thus not reflect for single events involving substantial losses
3 ALS Systems:3 ALS Systems:OSHA Incidence RateFatal Accident Rate (FAR)Fatality Rate, or Death per
Person per Year
OSHA Incidence RateOSHA Incidence RateBased on cases/100 worker yearsA standard worker year = 2000
hours◦50 weeks/year x 40 hours/week
Therefore, OSHA IR is based on 200,000 hours of worker exposure to a hazard◦100 worker years x 2000 hours
Number of lost workdays
Injury and illness (Equation 1)
Lost workdays (Equation 2)
Question 1.9 Question 1.9 (Crowl & Louvar, 2002)(Crowl & Louvar, 2002)
A university has 1200 full-time employees. In a particular year this university had 38 reportable lost-time injuries and 274 lost workdays. Compute the OSHA IR based on injuries and lost workdays.
Assume an employee works for 8hr, 250 days/year
Answers:Answers:OSHA IR (Injury and Illness) =
3.17OSHA IR (Lost workdays) = 22.83
FARFARBritish chemical industryBased on 1000 employees
working their entire lifetimeTotal working years/employee =
50 yearsTherefore, FAR is based on 108
working hours
Equation 3
Question 1.3 Question 1.3 (Crowl & Louvar, 2002)(Crowl & Louvar, 2002)
Assuming that a car travels at an average speed of 50 km/h, how many kilometres must be driven before a fatality is expected?
Assume FAR for travelling by car=57 deaths/108
Answer:Answer:Refer to table 1.4, FAR travelling
by car is 57 deaths/108 hours.Speed = 50 km/hA death will occur every 108/57 =
1.75 x 106 hours.Therefore, distance before a
death occur = 87.5 x 106 miles
Fatality RateFatality RateIndependent of the number of
hours actually workedBased on the general populationFAR Fatality rate
Question 1.5 Question 1.5 (Crowl & Louvar, 2002)(Crowl & Louvar, 2002)
A plant employs 1500 full-time workers in a process with a FAR of 5. How many industrial related deaths are expected per year?
Answer:Answer:Expected industrial related death
per year = 0.15
NATURE OF ACCIDENT PROCESS & SEQUENCE
Table 1: Common Chemical Table 1: Common Chemical Plant Accidents Plant Accidents (Crowl & Louvar, 2002)(Crowl & Louvar, 2002)
Type of Accident
Probability of Occurrence
Potential for Fatalities
Potential for Economic Loss
Fire High Low Intermediate
Explosion Intermediate Intermediate High
Toxic Release
Low High Low
Causes of LossesCauses of LossesMechanical failureOperator errorProcess upsetsNatural hazardsDesign FlawSabotage/ArsonUnknown ???
Accident 3-Step SequenceAccident 3-Step Sequence
InitiationPropagationTermination
InitiationInitiationThe event that starts the
accident
Example: Mr. A threw away a burned cigarette bud into dried bushes
PropagationPropagationThe event or events that maintain
or expand the accident
Example:A portion of dried bushes ignited, releasing thick smoke and hot flame. Fire starts to progress to another part of bushes
TerminationTerminationThe event or events that stop the
accident or diminish it in size.
Example:Consumption of combustible materials in process, fire extinguisher.
More example: refer to Table 1.7, Page 19 (Crowl & Louvar, 2002)