Car battery jump-starting

Each year, nearly 6,000 motorists suffer serious eye injuries or even blindness because of improperly jump-starting a dead vehicle battery. All vehicle batteries contain sulfuric acid and produce hydrogen and oxygen gases. If the hydrogen gas comes into contact with a spark, the battery can explode, sending pieces of the battery and acid flying.

Jumper cables and goggles

Essential equipment for jump starts

Here is a reminder of the safe steps to perform a car battery jump-start. Keep in mind that preventative maintenance is the best defense against battery failure. Check car batteries for cracks or corrosion as recommended by the manufacturer, and before each winter season.

Equipment to safely jump-start a vehicle

Jumper cables: You should have jumper cables tested and approved by the Society of Automotive Engineers (SAE), and are at least 12-feet long and color coded. Damaged cables (with rust, corrosion or exposed wires) may produce sparks, which can lead to battery explosion. Never use electrical tape to cover exposed wires.

Safety goggles: ANSI approved, splash-proof, and polycarbonate.

Flashlight: for low light situations.

Jump-starting do’s and dont’s


  • Turn off lights, heater and other electrical loads on vehicles.
  • Set parking brakes.
  • Make sure batteries are the same voltage.
  • Cover the vent caps of both batteries with a damp cloth.
  • Know the difference between the negative and positive battery terminals and the negative and positive clamps of the jumper cables. Positive is indicated by a (+) sign, the words “POS” and the color red; negative is marked by a (-) sign, the words “NEG” and the color black. The colors may vary but are red (+) and black (-) in most instances.
  • Call a professional if you think there might be trouble you can’t handle, or you can’t remember how to jump-start a vehicle.

DON’TLead acid battery

  • Attempt to jump-start a vehicle with a frozen battery.
  • Allow the two vehicles to touch each other.
  • Allow the jumper cables to touch each other.
  • Lean over the battery when making connections.
  • Smoke or operate anything that may cause a spark when working on a battery.

Jumper cable and starting steps

  1. Follow the do’s and don’ts
  2. Clamp one cable to the positive (+) terminal of the dead battery. Don’t let the positive cable touch anything metal other than the battery terminal.
  3. Connect the other end of the positive cable to the positive terminal of the good battery.
  4. Connect one end of the negative (-) cable to the negative terminal of the good battery.
  5. Connect the other end of the negative cable to metal on the engine block on the car with the dead battery. Don’t connect it to the dead battery, carburetor, fuel lines or moving parts.
  6. Start the car with the good battery.
  7. Start the stalled car.
  8. Remove the cables in reverse order.

What should you do if battery acid comes in contact with your skin or eyes?

The injured motorist should flush the affected area with the first drinkable liquid available, such as water, milk, juice or a soft drink. The eyes are particularly important to flush due to their delicate tissue. The longer you wait, the greater the chances of a serious eye injury. Flush the affected area for at least 15 minutes and immediately seek emergency medical attention.

References for this section

Michigan NETS Winter Driving Safety Tips

Jump-Starting a Car Battery FactSheet : From Texas Department of Insurance, Fact Sheet HS04-015B (12-06).

Lead Acid Battery Maintenance and Safety Protocol

Lead acid generator batteryLead-acid batteries are physically large batteries that contain lead plates in a solution of acid to create electricity. They are a common power source for many applications; mostly cars, boats, standby power generators. Each year a state employee is injured during the operation and maintenance of these batteries. Nationally, 2300 people are injured each year using lead acid batteries. Acid burns to the face and eyes comprise about 50% of these injuries as these batteries can easily explode. The remaining injuries were mostly due to lifting or dropping batteries as they are quite heavy.

Lead-Acid battery Basics

  • The electrolyte is a solution of sulfuric acid (35%) and water (65%). This solution can cause chemical burns to the skin and especially to the eyes.
  • During normal operation, water is lost from a non-sealed (or flooded) battery due to evaporation.
  • During charging, lead acid batteries produce hydrogen and oxygen gases (highly flammable/explosive) as electrolysis occurs.
  • Many lead acid explosions are believed to occur when electrolytes are below the plates in the battery and thus, allowing space for hydrogen/oxygen to accumulate. When the battery is engaged, it may create a spark that ignites the accumulated gases and causes the battery to explode.

Standard Precautions

  • Always store or recharge batteries in a well-ventilated area away from sparks or open flames
  • Damaged lead acid batteries shall be kept in properly labeled acid-resistant secondary containment structures.
  • Use only chargers that are designed for the battery being charged.
  • Always keep lead acid battery vent caps securely in place.
  • Do not store acid in hot locations or in direct sunlight.
  • Pour concentrated acid SLOWLY into water; do not add water into acid.
  • Use nonmetallic containers and funnels.
  • If acid gets into your eyes, flush immediately with water for 15 minutes, and then promptly seek medical attention.
  • If acid gets on your skin, rinse the affected area immediately with large amounts of water. Seek medical attention if the chemical burns appears to be a second degree or greater.
  • Never over charge a lead acid battery and only replenish fluid with distilled water.
  • Emergency wash stations should be located near lead-acid battery storage and charging areas.
  • Prevent open flames, sparks or electric arcs in charging areas.
  • Lead-acid storage and charging areas should be posted with “Flammable – No Smoking” signs.
  • Neutralize spilled or splashed sulfuric acid solution with a baking soda solution, and rinse the spill area with clean water.

What to do when servicing batteries

  • Keep metal tools and jewelry away from the battery.
  • Inspect for defective cables, loose connections, corroded cable connectors or battery terminals, cracked cases or covers, loose hold-down clamps and deformed or loosed terminal posts.
  • Replace worn or unserviceable parts.
  • Check the state of charge of non-sealed and sealed batteries with an accurate digital voltmeter while the engine is not running, and lights and other electrically-powered equipment are turned off. Also check the electrolyte levels and specific gravity in each cell of non-sealed batteries.
  • When checking the electrolyte liquid levels of the batteries use a rated flashlight that is intrinsically safe. In the event one is not available, Use a plastic/non-metallic flashlight, turn on the flash light prior to getting near the battery when checking cell levels and turn off the flash light when you are away from the batteries.
  • Follow the battery manufacturer’s recommendations about when to recharge or replace batteries.
  • Tighten cable clamp nuts with the proper size wrench. Avoid subjecting battery terminals to excessive twisting forces.
  • Use a cable puller to remove a cable clamp from the battery terminal.
  • Remove corrosion on the terminal posts, hold-down tray and hold-down parts.
  • Use a tapered brush to clean battery terminals and the cable clamps.
  • Wash and clean the battery, battery terminals, and case or tray with water. The corrosive acid can be neutralized by brushing on some baking soda (sodium bicarbonate) solution. If the solution does not bubble, the acid is probably neutralized. Rinse the battery with water to remove the baking soda solution.
  • To prevent shocks, never touch or come in contact with both terminals at the same time. If baking soda solution is applied with a cloth, remember that these solutions can conduct electricity.
  • When battery cables are removed, ensure that they are clearly marked “positive” and “negative” so that they are reconnected with the correct polarity.
  • Use a battery carrier to lift a battery, or place hands at opposite corners. Remember, batteries can weigh 30 to 60 pounds, so practice safe lifting and carrying procedures to prevent back injuries.
  • Use a self-leveling filler that automatically fills the battery to a predetermined level. Never fill battery cells about the level indicator.
  • Do not squeeze the syringe so hard that the water splashes acid from the cell opening.

Required safety equipment in the battery recharging area

  • Plumbed tepid water safety shower and eyewash station.
  • Personal or Portable eyewash stations may be installed in the area immediate to the battery charging, if plumbed units cannot be installed. However, plumbed tepid water wash stations must be installed nearby to facilitate the required flushing of the eyes and skin.
  • Non-vented safety goggles
  • Face shield (considered secondary safety protection)
  • Acid resistant gloves (neoprene is sufficient)
  • Apron (If there is a potential to spill acid)
  • Steel-toe boots or foot guards if the battery is lifted

Forklift Battery Information

  • Some forklifts use nickel-iron (Ni-Fe) batteries. The personal protective equipment (PPE) requirements will be similar to lead-acid battery handling, though you should verify the chemical resistance of the gloves against the potassium hydroxide electrolyte solution and select appropriately.
  • Note that the electrolytes used in lead acid (sulfuric acid) and nickel iron (potassium hydroxide) batteries are incompatible. If your facility has both types in use, take appropriate precautions to avoid mixing the solutions.
  • To protect against the danger associated with the battery’s weight, the batteries should only be removed and replaced from the forklifts using an appropriately equipped forklift or battery cart specifically designed for transporting batteries.
  • Batteries being removed should be securely placed and restrained in the cart or forklift to avoid dropping the battery.

Prior to starting the standby generator

  1. Check the engine starting batteries to determine if the batteries are sealed or unsealed lead acid.
  2. If the batteries are unsealed lead acid, check the electrolyte level in the battery before starting the generator.
  3. If the electrolyte is low and the plates are exposed, do not start the generator. Add distilled water to the electrolyte to specified level in battery.
    • Wear gloves, safety glasses/goggles, face shield and apron.
    • Follow the instructions for adding water.
  4. Wait at least an hour to allow time for the hydrogen gas generated in the battery to dissipate in the environment.

Sources for more information

  • 29 CFR 1910.178, Powered Industrial Trucks
  • 29 CFR 1910.151, Medical Services and First Aid
  • ANSI/ASME B56.1-1993, Safety Standards for Low Lift and High Lift Trucks
  • ANSI/NFPA 505, Powered Industrial Trucks Including Type, Area Use, Maintenance and Operation.
  • Powered Industrial Truck Owner’s Manual
  • ANSI Z358.1 – 1998



This publication was prepared for environmental, health and safety staff at University of Wisconsin System campuses, to assist in finding resources and information for regulatory compliance. It is not intended to render legal advice.

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