Safety Advisory: Automatic Slack Adjusters

Manual Adjustment of Automatic Slack Adjusters May Contribute to Unexpected Brake Failure on Automotive Fire Apparatus. NIOSH recommends that all fire departments operating fire apparatus equipped with automatic slack adjusters (ASAs) immediately take the following actions to reduce the risk of fire fighters being injured in an apparatus crash due to brake failure:

Ensure that ASAs are not manually adjusted.

Establish procedures to ensure maintenance on fire apparatus is conducted as recommended in NFPA 1911
Standard for the Inspection, Maintenance, Testing, and Retirement of In-Service Automotive Fire Apparatus.

Ensure maintenance is only performed by qualified technicians who meet NFPA 1071 Standard for Emergency Vehicle Technician Professional Qualifications.