How much do I breathe?

Air Intake Factors

The first factor in calculating the PEL is air. How much air does a person breathe? The answer depends on a number of factors.

Fitness Level


For the construction industry we’re going to make an assumption that the average adult male employee works at a moderate activity level. Looking at this chart, we’ll use 35 liters per minute, an activity level right between a brisk walk and mowing the lawn.

1 min = 35 liters

The average adult male working at a moderate activity level inhales 16.8 cubic meters of air over the course of an 8-hour work day.

The Math

As a visual reference, Joel is standing in the middle of a 16.8-meter cube that represents the quantity of air inhaled in during an 8 hour workday.

1 min = 35 liters

1 hour = 2100 liters

2100 liters/hour x 8 hours =
16,800 liters per day

Or 16,800 liters ÷ 1000 liters

= 16.8 m3