Air filtration in gun ranges is necessary to protect workers and visitors from inhaling hazardous airborne particles generated by gunfire, such as lead, copper, and other heavy metals. The following are some of the air filtration requirements for gun ranges:

1. Use of HEPA filters: HEPA filters are necessary to remove fine particulate matter generated by gun firing from the air. These filters have a minimum efficiency of 99.97% at removing particles as small as 0.3 microns.
2. Ventilation rates: Ventilation rates for gun ranges are typically higher than those for commercial or residential buildings. The National Institute for Occupational Safety and Health (NIOSH) recommends a minimum of six air changes per hour (ACH) for gun ranges.
3. Air pressure control: In addition to filtration and ventilation, air pressure control may be necessary to prevent the spread of airborne particles to other areas of the building. Negative air pressure is used to contain the air inside the shooting range, while positive air pressure can be used in adjacent areas to prevent contaminated air from entering.
4. Regular maintenance and monitoring: Regular maintenance and monitoring of air filtration systems in gun ranges are critical to ensure that they are functioning correctly and providing the necessary level of air cleanliness. This includes regular filter replacement, cleaning of air ducts and ventilation systems, and monitoring of air quality levels.

In addition to the above, gun ranges must comply with regulatory standards set by organizations such as OSHA and the Environmental Protection Agency (EPA). Proper air filtration in gun ranges is essential for protecting the health and safety of workers and visitors. 

Colorado Air Filter works with numerous indoor firing ranges within Colorado and can assist when designing and replacing air filters within Indoor firing ranges.