COSS - Certified Occupational Safety Specialist Incident Rate Calculations Questions and Answers

Question 1

A manufacturing company with 150 full-time employees, each working 2,000 hours per year, experienced 7 OSHA recordable incidents. What is the company's Total Recordable Incident Rate (TRIR)?

Accepted Answer

4.67

Answer

The TRIR is calculated using the formula: (Number of Recordable Incidents × 200,000) / Total Hours Worked. First, calculate total hours: 150 employees * 2,000 hours/employee = 300,000 hours. Then, apply the formula: (7 * 200,000) / 300,000 = 1,400,000 / 300,000 = 4.67.

Question 2

When calculating incident rates like TRIR or DART, what does the 200,000 figure in the formula represent?

Accepted Answer

The equivalent hours worked by 100 full-time employees in a calendar year.

Answer

The 200,000 figure is a standard base used by OSHA to normalize the data. It represents the hours that 100 employees would work in a year, assuming each works 40 hours per week for 50 weeks (100 employees x 40 hours/week x 50 weeks/year = 200,000 hours). This allows for comparison between companies of different sizes.

Question 3

A construction company logged 525,000 hours worked in a year. During this period, they had 3 incidents that resulted in days away from work and 2 incidents that required job restrictions. What is the company's DART rate?

Accepted Answer

1.90

Answer

The DART (Days Away, Restricted, or Transferred) rate includes only incidents that result in those outcomes. The formula is: (Number of DART Incidents × 200,000) / Total Hours Worked. Here, the number of DART incidents is 3 + 2 = 5. So, (5 * 200,000) / 525,000 = 1,000,000 / 525,000 = 1.90.

Question 4

Which of the following incidents would be included when calculating a company's DART (Days Away, Restricted, or Transferred) rate?

Accepted Answer

An employee is assigned to light-duty tasks for one week while recovering from a work-related back strain.

Answer

The DART rate specifically tracks incidents that are severe enough to cause an employee to have days away from work, be placed on restricted work activity, or be transferred to another job. An assignment to light-duty tasks is a form of restricted work activity and is therefore included in the DART calculation.

Question 5

A safety manager is calculating the company's annual TRIR. Which of the following data points should be EXCLUDED from the 'Total Hours Worked' calculation?

Accepted Answer

Paid vacation and sick leave hours for all employees.

Answer

When calculating total hours worked for incident rates, only actual hours worked should be included. Time off, such as paid vacation, sick leave, or holidays, is not included in the calculation. Hours worked by temporary or salaried employees are included.

COSS - Certified Occupational Safety Specialist Practice Test

COSS - Certified Occupational Safety Specialist Practice Test

COSS - Certified Occupational Safety Specialist Incident Rate Calculations Questions and Answers