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Safety Precautions Essential safety precautions for working on classic and antique vehicles. Review these guidelines before performing any service — they are provided in full and apply to every procedure on this site.
General Shop Safety
Always wear ANSI-approved safety glasses when working under a vehicle, grinding, drilling, or handling chemicals. Use jack stands rated for the vehicle weight — never rely on a hydraulic jack alone to support a vehicle. Keep a properly rated fire extinguisher (Class B minimum) within reach at all times. Work in well-ventilated areas. Carbon monoxide from running engines is odorless and deadly. Disconnect the battery negative terminal before working on any electrical system. Remove rings, watches, loose clothing, and tie back long hair before working near rotating parts. Chemical Safety
Brake fluid, antifreeze, and transmission fluid are toxic — avoid skin contact and ingestion. Antifreeze is sweet-tasting and attractive to children and animals. Battery acid (sulfuric acid) causes severe burns. Wear acid-resistant gloves and eye protection when servicing batteries. Neutralize spills with baking soda. Gasoline vapors are heavier than air and extremely flammable. Never use gasoline as a cleaning solvent. Vehicles manufactured before 1978 may contain asbestos in brake linings, clutch facings, and gaskets. Never blow brake dust with compressed air — use approved wet-cleaning methods. Used engine oil contains known carcinogens. Minimize skin contact and dispose of properly at approved recycling facilities. Refrigerant (R-12 in pre-1994 vehicles) displaces oxygen and can cause frostbite. Never vent refrigerant to the atmosphere — it is a violation of federal law. Electrical Safety
Automotive batteries produce hydrogen gas during charging — a spark can cause an explosion. Keep open flames and sparks away. The ignition system produces voltages up to 40,000 volts. Never touch ignition wires or coil terminals while the engine is running or cranking. When jump-starting, connect positive (+) to positive first, then ground the negative (-) cable to the engine block — not the battery terminal — to avoid sparks near the battery. Verify circuit capacity before installing accessories. Overloaded wiring causes fires. Always use properly rated fuses and fusible links. Lifting & Support
Always lift vehicles on designated lift points specified in the factory service manual. Incorrect placement can crush rocker panels, bend frames, or cause the vehicle to fall. Before sliding under a vehicle, shake it firmly to verify stability on the jack stands. Place wheel chocks on the opposite end of the vehicle from where it is being raised. When using a two-post lift, position arms to balance the vehicle's center of gravity. Front-heavy vehicles (large V8s) require arms positioned further forward. Never exceed the rated capacity of any jack, jack stand, or lift.