Auto repair safety tips

If you decided to do auto repair work on your own to save money, don’t forget that it can be dirty and dangerous work.
Here are top tips which can help you to avoid dangers during auto repairs. Most of these tips are common sense warnings, but there may be some things you are not aware of that could pose a potential danger.
Very important, if you feel unsure about a repair, better to leave it to a professional mechanic to finish the job. Most modern vehicles are designed with a complex system. That’s why it is essential to have special skills, tools and equipment, and the experience as well, to do repair works. One simple mistake can destroy whole electronic components of the vehicle which can cost you a lot.

Know your physical limits. Sometimes, replacing some parts require physical strength, for example, changing or removing tires, pulling a cylinder head, or crawling under the vehicle, laying or working in an awkward position, reaching, bending, twisting, pulling, tugging, straining, jerking and motions and so on. If you are not physically able to do the work, then ask someone to do it for you.

Be focused. If you feel tired, not feeling well, tipsy, intoxicated, on medication or otherwise impaired, do not start repair job, because they may affect your judgment and perception creating a potential for injury or error.


  • Do NOT smoke when working on any fuel related components (fuel filter, carburetor, fuel injectors, fuel pump, fuel tank or fuel lines).

  • Keep a fire extinguisher easily accessible. The fire extinguisher should have a "B" (liquids & grease fires) and "C" (electrical fires) rating.

  • Do NOT smoke or get any sparks near the battery. Batteries contain very explosive hydrogen gas. If jump starting a battery, make the final jumper connection to the engine or chassis.

  • NEVER work underneath a vehicle unless it has been appropriately supported. Always use two support stands to hold the car up, never trust a jack alone. Make sure the weight ratings on the support stands is more than adequate to hold up the vehicle's weight, too. Do not use blocks of wood, boxes, wheels or bricks for supports because they may slip and allow the car to fall.

  • Always disconnect the battery when working on electrical systems and near/around electrical wiring. For example, when replacing a starter, installing a radio, fixing a broken switch or wiring, etc. This will prevent accidental shorts that could damage the wiring or start a fire. When working under the dash, remember to disconnect the airbag to avoid accidentally setting it off. Airbags can cause injury and are expensive to replace.

  • Never leave the key in the ignition switch, as the key can draw an electrical charge from the battery. Always remove the keys from the ignition switch. Also, avoid unplugging fuses and wiring harnesses while the key is in the “on” position. Otherwise, there is a risk of electrical shock or electrical spikes that may damage electronic parts and wiring.

  • Never wear loose clothing or clothing that is ripped or torn, jewelry, rings, neckties, scarves when working on your vehicle. If you have long hair, tie it back or cover it. These items may become entangled in pulleys or moving parts causing serious injury, dismemberment or death!

  • Watch out for moving parts such as drive belts, pulleys, fans, and other moving parts when working under the hood if the engine is running. The moving parts and components could cause injury to a person or the vehicle itself.

  • Be aware of the vehicle’s temperature before beginning any work. If the engine is running or the car has been driven within the past half hour or so. The engine, manifold, exhaust system, and radiator could be hot and cause skin burns. Plus, the radiator coolant is still pressurized.

  • NEVER open the radiator cap on a hot engine. Always leave the engine to cool down for at least an hour before opening the cap. Even then, use extreme caution. Place a rag over the cap, then loosen it slowly to the first detent or stop. At this point, any extra pressure and steam should be released. Wait until all pressure has escaped before removing the cap the rest of the way.

  • Avoid electrical shocks when working around the ignition system. The average battery voltage in passenger car and light truck electrical systems is only 12 volts and will not harm you. But the ignition system bumps the primary voltage up to 25,000 to 40,000 volts which can give you a nasty shock if you touch a spark plug wire, the ignition coil or distributor cap while the engine is running. On hybrid vehicles, the hybrid battery may contain up to 300 or more volts, which can kill or injure you. Do not touch any ORANGE high voltage cables unless the hybrid battery has first been disconnected. Also, wear Class 0 rated rubber gloves that can withstand up to 1000 volts.

  • Wear protective gear at all times. Eye protection, gloves, and ear protection should be worn when making certain types of repairs. For example, eye protection, when working under the vehicle (to keep dirt and debris from falling into your eyes), when pounding or grinding on anything (to prevent metal chips out of your eyes), when jump-starting the battery (to keep acid out of your eyes should the battery explode), when working on air conditioning components (to keep refrigerant out of your eyes), and/or when doing anything that might pose a risk to your sight. Ear protection, when using loud pneumatic tools or when hammering, pounding, grinding, sawing, drilling, etc. Prolonged exposure to high levels of noise can cause permanent hearing loss.

  • Wear breathing protection (an OSHA-approved mask when spray painting or using other chemicals that give off aromatic hydrocarbons. A dust mask is recommended when grinding, sanding or sandblasting. A dust mask will NOT provide any protection against paint or chemical fumes. DO NOT use an air hose to blow brake dust off brake components. Brake dust may contain asbestos or other fibers that can cause lung disease if inhaled. Use a liquid cleaner to remove brake dust. When using aerosol products that contain VOCs or solvents (spray paint, throttle cleaner, brake cleaner, etc.), use in a well-ventilated area, avoid breathing the fumes and wear proper breathing protection. The best place to use such products is outdoors, or in a large garage with the door open, or with a ventilation fan that exchanges the dirty inside air for fresh outside air.

  • Do not open any brake lines or replace any components in a vehicle equipped with an "integral" ABS system (one where the master cylinder is combined with the ABS modulator, pump and pressure accumulator) without first depressurizing the system. This can usually be done by depressing the brake pedal 24 to 40 times while the key is off.

  • Use caution when opening any fuel lines on a fuel injected vehicle. The pressure in some systems may be as high as 80 to 90 psi when the engine is running. So do not open any fuel line while the engine is running unless your fire insurance and life insurance are both paid up. Residual fuel pressure can remain in the lines for many hours after the engine has been shut off. To minimize fuel spray, wrap a rag around the hose or line before loosening it, or relieve pressure in the line using a procedure approved by the vehicle manufacturer (refer to a shop manual for details).

WARNING: On diesel engines, the fuel pressure inside the fuel lines between the injection pump and fuel injectors is exceptionally high when the engine is running (500 to 5000 psi or higher depending on engine speed and type of injection system!). Never start a diesel engine with a fuel line or injector disconnected.

  • Keep away children, pets, spouses or others who may distract you from your work. This will reduce the risk of injury and making a mistake.

  • Avoid shock hazards with extension cords & electrical tools. If you are working outdoors and using power tools, make sure the extension cord you are using is rated for outdoor use, that the extension cord and tools are properly grounded (a "ground fault interrupt" outlet is recommended), and that the cord has the proper amp rating for the tools you are using. DO NOT use an adapter plug to convert a three-prong grounded plug into a two-prong plug.