# Shop Safety Hazards Part of the Automotive Maintenance Merit Badge Digital Resource Guide: [Introduction & Overview](https://merit-badge.university/merit-badges/automotive-maintenance/guide/index.md) *1. Safety & Registration* > **1a.** Explain to your counselor the hazards you are most likely to encounter during automotive maintenance activities, and what you should do to anticipate, help prevent, mitigate, or lessen these hazards. Working on vehicles is rewarding, but a garage or shop is full of real dangers. Heavy parts, toxic chemicals, hot surfaces, and moving components can cause serious injuries if you are not careful. The good news is that almost every accident in a shop is preventable. Knowing the hazards before you start is the first step to staying safe. > **Safety First!** > > Never work on a vehicle alone. Always have a responsible adult present who can help in an emergency. This is not optional — it is the most important safety rule in the shop. ### Chemical Hazards You will encounter many chemicals when working on a car. Engine oil, brake fluid, coolant (antifreeze), transmission fluid, and battery acid are all hazardous in different ways. - **Coolant/antifreeze** has a sweet smell and taste that attracts animals and small children, but it is highly toxic. Even a small amount can be fatal if swallowed. Always clean up spills immediately and store containers with tight lids. - **Brake fluid** is corrosive — it can damage paint and irritate your skin and eyes. Wear gloves and safety glasses whenever you handle it. - **Battery acid** (sulfuric acid) can cause severe chemical burns. Never tip a battery on its side, and always wear eye protection when working near one. - **Used motor oil** contains carcinogens (cancer-causing compounds) absorbed during engine operation. Avoid prolonged skin contact and always wash your hands thoroughly after handling it. > **Tip** > > Keep a bag of oil-absorbent material (cat litter works in a pinch) in your garage. If you spill oil or coolant, spread it over the spill immediately to keep the liquid from spreading — then sweep it up and dispose of it properly. ### Physical Hazards Cars are heavy — a typical sedan weighs around 3,500 pounds. When you lift a vehicle with a jack, you are holding thousands of pounds overhead. If the jack fails or the car slips, the results can be fatal. - **Crushing injuries** are the most serious risk. Never work under a vehicle supported only by a jack. Always use jack stands rated for the vehicle's weight. - **Burns** can come from hot engine parts, exhaust components, or radiator fluid. An engine that has been running can have surface temperatures above 200°F. Let the engine cool before working near hot components. - **Cuts and scrapes** from sharp metal edges, broken parts, and hand tools are common. Keep your tetanus vaccination up to date. - **Back injuries** happen when you lift heavy parts like batteries, wheels, or engine components without proper technique. Lift with your legs, not your back, and ask for help with heavy items. > **Be Prepared! A Vehicle Slips Off the Jack** > > If you hear creaking, see the vehicle shifting, or notice a jack leaning: > > - **Get out immediately.** Do not try to reposition the jack or save your tools. > - **Never put any part of your body under a vehicle that is not on jack stands.** > - Once clear, assess the situation. Reposition the jack on level, solid ground and always use jack stands before going back under. ### Electrical Hazards A standard car battery operates at 12 volts, which is not enough to shock you through dry skin — but it can deliver hundreds of amps of current. That is enough to heat a wrench red-hot in seconds if it accidentally bridges the battery terminals, potentially causing burns or starting a fire. Hybrid and electric vehicles present a much greater electrical danger. Their high-voltage battery packs operate at 200 to 800 volts — more than enough to cause a fatal shock. We will cover high-voltage safety in detail in Requirement 1d. > **Safety First!** > > Always disconnect the negative (black) battery terminal first when working on the electrical system. This prevents accidental short circuits. When reconnecting, attach the positive (red) terminal first, then the negative. ### Fire and Explosion Hazards Gasoline vapors are extremely flammable and heavier than air, so they collect in low spots like pits and floor drains. A single spark — from a tool, a light switch, or static electricity — can ignite them. - Never smoke in or near a garage. - Keep a fire extinguisher rated for Class B (flammable liquids) and Class C (electrical) fires within reach. - Store gasoline and other flammable liquids in approved containers, away from heat sources. ### Exhaust Hazards Running an engine in an enclosed space produces carbon monoxide (CO), a colorless, odorless gas that can kill within minutes. Always ensure adequate ventilation when an engine is running indoors. If the garage door must be closed, use a tailpipe exhaust hose vented to the outside. > **Did You Know?** > > Carbon monoxide binds to your red blood cells over 200 times more strongly than oxygen does. Even at low concentrations, it quietly replaces the oxygen in your blood. By the time you feel dizzy or confused, you may already be too impaired to get yourself to safety — which is why ventilation and CO detectors are non-negotiable in any garage. ![A well-organized garage workspace with safety equipment visible: fire extinguisher on wall, jack stands under a car, safety glasses and gloves on a workbench, and a clearly marked first-aid kit](https://ik.imagekit.io/doulacoop/tr:w-800/mbu-assets/merit-badges/automotive-maintenance/guide/shop-safety-overview?v=a74af981) ### Anticipate, Prevent, Mitigate Your counselor will want to hear you use these three concepts: - **Anticipate:** Before you start any job, look around the workspace. What could go wrong? Is the floor slippery? Is the car securely supported? Are flammable materials nearby? - **Prevent:** Take action to stop hazards from becoming injuries. Wear protective gear, use the right tools, follow procedures, and keep your workspace clean and organized. - **Mitigate:** If something does go wrong, know how to minimize the damage. Know where the fire extinguisher is. Know how to shut off the engine. Know basic first aid. Have a phone nearby to call for help. [OSHA Automotive Repair Safety](https://www.osha.gov/automotive-repair): Federal safety guidelines for automotive repair shops — many of the same principles apply to home garages. Video: [Automotive Repair Safety Observations](https://youtu.be/g52rQbJd43w?si=5YRRnfneJqWspPMb) --- - Previous: [Introduction & Overview](https://merit-badge.university/merit-badges/automotive-maintenance/guide/index.md) - Next: [Safety Equipment & Clothing](https://merit-badge.university/merit-badges/automotive-maintenance/guide/req1b/index.md)