Safety and Compliance
Safety and compliance questions on the T8 exam test whether you can protect yourself, the vehicle, and the public while working on medium/heavy trucks. Know the hierarchy of hazard controls: engineering controls and safe work practices come before PPE, and PPE is the last line of defense. Master the rules that show up repeatedly: chock wheels before any work under a raised vehicle, use cribbing or stands rated for the load (never rely on hydraulics alone), and set the parking brake plus wheel chocks before crawling underneath. Understand lockout/tagout for air and electrical systems, proper blocking of suspension and air-bag components, and the danger of stored energy in air brake reservoirs and hydraulic accumulators.
Hazmat and environmental compliance is a frequent trap area. Used oil, filters, coolant, and brake fluid are regulated waste streams; absorbent cleanup and labeled containers matter. Know DOT out-of-service criteria concepts at a high level-brake adjustment limits, tire tread depth, and lighting-because inspection questions often hinge on whether a defect is an out-of-service condition. Also recognize OSHA fundamentals: eye/face protection when grinding or blowing with compressed air, hearing protection in high-noise bays, and never using compressed air to clean your body.
Question traps: confusing "should" with "must," assuming a jack is a support device, or forgetting that a vehicle can move from stored air or gravity. Another common trap is treating a warning tag as optional.
Rule of thumb: if the vehicle is raised and any part of you goes under it, it must be mechanically supported and the wheels chocked-no exceptions. Worked example: a tech jacks a tractor to inspect a slack adjuster. Correct sequence: chock wheels, raise with jack, place rated stands under the frame/axle, lower jack so stands carry load, then inspect.