Estimating Work Rates & Loads

Employers can ensure that work schedules are created appropriately by using the following categories to help estimate the types of physical strain associated with each task. The greater the physical strain, the greater the risk of instigating heat-related stress and illness.

Rest involves activities such as sitting.

Light activity involves sitting while holding something, standing while holding something, casual walking, driving, or lifting 10 pounds or fewer.

Moderate activity includes sustained periods of arm or hand work, moderate arm and leg work, moderate pushing and pulling, walking at a moderate speed, lifting 10 pounds 10 times per minute, or lifting 25 pounds six times per minute.

Heavy activity involves intense arm and trunk work, carrying a load, shoveling, sawing, walking at a fast pace, pushing or pulling heavy loads, lifting 10 pounds 14 times per minute, or lifting 25 pounds 10 times per minute.

Very Heavy activity is defined as very intense activity performed at a fast or maximum pace, jogging or running faster than four miles per hour, lifting 10 pounds more than 18 times per minute, or lifting 25 pounds more than 13 times per minute.

To learn more about Heat Stress visit our Heat Stress, Illness & Injury Safety Online Training web page.