Question

The Occupational Safety and Health Administration (OSHA) mandates certain regulations that have to be adopted by corporations. Prior to the implementation of the OSHA program, a company found that for a sample of 40 randomly selected months, the mean employee time lost due to job-related accidents was 45 hours. After implementation of the OSHA program, for a random sample of 45 months, the mean employee time lost due tojob-related accidentswas 39 hours. It can be assumed thatthe variability of time lost due to accidentsis about the same before and after implementation of the OSHA program (with a standard deviation being 3.5 hours). (a) Find a 90% confidence interval for the difference in the mean time lost due to accidents. (b) Test the hypothesis that implementation of the OSHA program has reduced the mean employee lost time. Use a level of significance of 0.10

Answer 1

Answer:

Null HYpothesis : H0 : Mean time lost due to job - related accidents are same as after implementing OSHA program as earlier.  

Alternative Hypothesis :

Ha : Mean time lost due to job - related accidents has been decreased after implementing OSHA program

Step-by-step explanation:

In these situations, you must evaluate the employee’s work duties and environment to decide whether or not one or more events or exposures in the work environment either caused or contributed to the resulting condition or significantly aggravated a preexisting condition.

preexisting injury or illness has been significantly aggravated, for purposes of OSHA injury and illness recordkeeping, when an event or exposure in the work environment results in any of the following: (i) Death, provided that the preexisting injury or illness would likely not have resulted in death but for the occupational event or exposure. (ii) Loss of consciousness, provided that the preexisting injury or illness would likely not have resulted in loss of consciousness but for the occupational event or exposure. (iii) One or more days away from work, or days of restricted work, or days of job transfer that otherwise would not have occurred but for the occupational event or exposure. (iv) Medical treatment in a case where no medical treatment was needed for the injury or illness before the workplace event or exposure, or a change in medical treatment was necessitated by the workplace event or exposure