COSS Incident Rate Calculations 4 — Questions and Answers
Question 1: A company employs 50 temporary workers supplied by a staffing agency who work on-site full time. Whose OSHA 300 log should record their injuries?
- The staffing agency's log only
- The host employer's log only
- Whichever employer supervises day-to-day work (Correct answer)
- Both logs simultaneously
Correct answer: Whichever employer supervises day-to-day work
OSHA requires the employer who supervises the employee's day-to-day work to record the injury, which is typically the host employer for on-site temp workers.
Question 2: The 'days away' count on the OSHA 300 log for a single case is capped at:
- 30 days
- 90 days
- 180 days (Correct answer)
- No cap applies
Correct answer: 180 days
OSHA caps the number of days away from work or restricted/transferred at 180 days for recording purposes on the 300 log.
Question 3: A worker is injured on a Monday and returns to full duty Thursday. How many days away from work are recorded?
- 0 days
- 2 days (Correct answer)
- 3 days
- 4 days
Correct answer: 2 days
Days away = Tuesday and Wednesday (the day of injury is NOT counted); returning Thursday means 2 calendar days away.
Question 4: To calculate a fatality rate per 100,000 workers, the formula denominator uses:
- 200,000 hours
- 2,000,000 hours (Correct answer)
- 100,000 workers × 2,000 hours = 200,000,000 hours
- 100 workers
Correct answer: 2,000,000 hours
Fatality rate = (fatalities × 200,000,000) / total hours, because 100,000 workers × 2,000 hours/year = 200,000,000 — but it is commonly expressed as fatalities per 100,000 workers directly.
Question 5: A company's TCIR dropped from 5.0 to 2.5 year over year while hours worked doubled. The most accurate interpretation is:
- Absolute number of injuries fell by half
- The injury rate improved even if absolute cases stayed the same (Correct answer)
- More injuries occurred but the rate looks better
- The data is not comparable across years
Correct answer: The injury rate improved even if absolute cases stayed the same
Rates normalize for workforce size; if hours doubled and TCIR halved, absolute cases could stay constant yet the rate still shows meaningful improvement per exposure hour.
Question 6: Which of the following is a leading indicator, as opposed to the lagging indicator represented by TCIR?
- Number of recordable injuries last quarter
- Near-miss reporting rate (Correct answer)
- Days away from work total
- DART rate
Correct answer: Near-miss reporting rate
Near-miss reporting rate is a leading indicator that predicts future risk, while TCIR, DART, and days away are lagging indicators reflecting past injuries.
Question 7: An OSHA 300 recordable illness is required when a work-related illness results in:
- Any doctor visit regardless of treatment
- Days away, restricted duty, medical treatment beyond first aid, loss of consciousness, or diagnosis by a healthcare professional (Correct answer)
- Only days away from work
- Only fatalities
Correct answer: Days away, restricted duty, medical treatment beyond first aid, loss of consciousness, or diagnosis by a healthcare professional
OSHA's general recording criteria require logging any work-related injury or illness meeting any one of these thresholds: death, days away, restricted/transfer, medical treatment beyond first aid, loss of consciousness, or significant diagnosis.
COSS Incident Rate Calculations 4
A company employs 50 temporary workers supplied by a staffing agency who work on-site full time.
Whose OSHA 300 log should record their injuries?