COHN Ergonomics and Physical Hazards Questions and Answers

Question 1

An occupational health nurse is conducting an ergonomic assessment of a workstation for an employee who performs data entry for 8 hours a day. The nurse utilizes the Rapid Upper Limb Assessment (RULA) tool. This tool is MOST appropriate for this task because it specifically evaluates:

Accepted Answer

Biomechanical and postural load on the neck, trunk, and upper extremities.

Answer

The Rapid Upper Limb Assessment (RULA) tool is specifically designed to assess the biomechanical and postural loads on the upper body, including the neck, trunk, and arms. It is ideal for evaluating sedentary tasks like data entry where the risk is concentrated in the upper extremities. The other options are incorrect: REBA assesses the entire body, the NIOSH Lifting Equation assesses lifting tasks, and HAVS is related to vibration exposure.

Question 2

A manufacturer implements a new process that requires workers to use a handheld pneumatic wrench. After several months, a worker reports intermittent blanching (whitening), numbness, and tingling in their fingers, especially in cold conditions. The occupational health nurse should recognize these symptoms as most characteristic of which physical hazard-related condition?

Accepted Answer

Hand-Arm Vibration Syndrome (HAVS)

Answer

Hand-Arm Vibration Syndrome (HAVS), also known as Vibration White Finger, is caused by regular, prolonged exposure to vibrating hand tools. Its characteristic symptoms include vascular effects like finger blanching (Raynaud's phenomenon), neurological effects like numbness and tingling, and musculoskeletal issues. The use of a pneumatic wrench is a common risk factor for HAVS.

Question 3

An occupational health nurse is part of a team tasked with reducing the risk of low back injuries in a warehouse. They are using the Revised NIOSH Lifting Equation to calculate the Recommended Weight Limit (RWL) for a specific lifting task. Which of the following factors is a key variable in this equation?

Accepted Answer

The horizontal distance of the load from the worker's body.

Answer

The Revised NIOSH Lifting Equation uses several task-specific variables to determine a Recommended Weight Limit (RWL). One of the most critical is the Horizontal Multiplier (HM), which is based on the horizontal distance of the hands from the midpoint between the ankles (H). The farther the load is held from the body, the lower the RWL will be. The worker's personal characteristics (age, gender, medical history) and ambient temperature are not direct inputs into the equation itself.

Question 4

A company's safety committee, including the occupational health nurse, is reviewing controls for a noisy manufacturing area. They have already provided all affected employees with hearing protection. According to the hierarchy of controls, which of the following actions represents a more effective long-term solution?

Accepted Answer

Enclosing the primary noise-producing machine in an acoustic barrier.

Answer

The hierarchy of controls prioritizes methods from most to least effective: Elimination, Substitution, Engineering Controls, Administrative Controls, and Personal Protective Equipment (PPE). Enclosing the machine is an engineering control, which physically isolates people from the hazard and is more effective than administrative controls (like job rotation) or relying on PPE (hearing protection), which is the least effective control.

Question 5

According to OSHA's Occupational Noise Exposure standard (29 CFR 1910.95), an employer is required to implement a hearing conservation program when the time-weighted average (TWA) noise exposure equals or exceeds what level?

Accepted Answer

85 dBA over an 8-hour shift

Answer

OSHA requires employers to implement a hearing conservation program when employee noise exposures equal or exceed the action level of 85 decibels on the A-scale (dBA) as an 8-hour time-weighted average (TWA). The Permissible Exposure Limit (PEL) is 90 dBA, at which point engineering or administrative controls are required.

COHN Exam Practice Test

COHN Exam Practice Test

COHN Ergonomics and Physical Hazards Questions and Answers