Keeping things safe while working with batteries

Batteries contain diluted sulphuric acid and emit hydrogen gas which can produce an explosive mixture. It is advised to follow these safety precautions at all times.

Handling battery acid

  • Always wear a face shield and protective clothing
  • Take extreme care to avoid spillage or splashing as it can destroy clothing and cause damage to the skin if not treated promptly
  • Be especially cautious when lifting batteries in polypropylene containers as pressure on the end walls could result in acid being ejected through the vent plugs
  • If acid is spilt onto clothing or the skin, neutralise it immediately with a solution of water and baking soda or household ammonia and then rinse with clean water
  • If acid enters the eye, force the eye open and flood with cool, clean water for approximately fifteen minutes
  • If acid is swallowed, drink large quantities of water or milk, followed with milk of magnesia. Do not encourage vomiting and seek medical advice as soon as possible.
  • Electrolyte spilt on the surface of a car should be neutralised and rinsed with clean water
  • Concentrated sulphuric acid should not be diluted by non-qualified personnel
  • Make sure your battery is supplied in a filled and charged condition and that it doesn’t require acid to be added (except in the case of spillage)
  • If your battery requires acid to be added, seek advice from your car manufacturer or visit your nearest Battery Centre.


Danger of explosions


Only trained personnel should work on a battery and should observe the following safety precautions,

  • Ensure you have the appropriate protective wear before working on a battery
  • Be familiar with the correct procedures when charging, testing or jump starting a vehicle
  • Follow the manufacturer’s instructions when using a charger or tester
  • Hydrogen and oxygen are produced as a part of the operation of the battery and can produce an explosive mixture within the battery and escape through the vents
  • Many modern batteries incorporate a flame arrester but it is still essential to keep any form of ignition well away from the battery
  • An exploding battery can cause severe injury from flying pieces of container and acid
  • Avoid leaning over the battery when charging, testing, jump starting, connecting or disconnecting
  • Do not break live circuits at the terminals as this causes a spark
  • Ensure the charger cable clamps and jump start leads are in good order and the connections are good
  • A poor connection can cause an electrical arc which can ignite the hydrogen gas and cause an explosion
  • Avoid dropping tools across the terminals and use insulated spanners
  • Do not smoke or expose battery to a flame.


Charging a battery

A battery should be charged in a well-ventilated area. Do not remove the vent plugs during charge except when taking specific gravity readings or topping up. Follow the charger manufacturer’s instructions,

  • Make sure that the charger is switched off before connecting to the battery.
  • Connect the charger leads to the battery terminals with the red positive (+) lead to the positive terminal and the black or blue negative (-) lead to the negative terminal.
  • The battery should not be charged while connected to the vehicle as the voltages reached during charge can damage the vehicle’s electrical system.
  • Never touch the charger leads while the charger is switched on. This could break the circuit creating a spark which could result in an explosion.

Battery acid

Take care when working with battery acid as it has the following dangerous properties,

  1. Corrosive – will cause serious burns to skin, eyes and clothing. Inhalation of fumes will damage mucous membranes and lungs. Ingestion will severely burn.
  2. Flammable – contact with most metals will release flammable and explosive hydrogen gas. Fire will produce irritating and toxic fumes.
  3. Environment – spillages not properly contained will cause environmental pollution.

Safety precautions

  • Wear protective clothing – face, foot, hand protection and PVC apron.
  • When mixing add acid to water.
  • Handle containers carefully to avoid spillage.


Storage and handling

  • Store in a dedicated containment area.
  • Store containers upright with caps securely fastened.
  • Do not stack containers.
  • Store in a cool dry place.
  • Do not store incompatible chemicals together.
  • Provide spill kit to treat spillages.

In case of emergency, do the following:



Remove personnel from area

Wear correct protective clothing

Isolate area

Use CO2 or water spray

Move containers if safe

Do not use jets of water

Do not allow fire water or acid to enter drain systems.



Eliminate any source of ignition

Wear correct protective clothing

Dam acid and prevent entry into drains, waterway & sewers

Stop leakage

Clean up using absorbent material

Dispose of spill material as hazardous material.

 ExposureAlways seek medical attention

Eyes – rinse with cool running water for at least 15 minutes

Skin – wash thoroughly with cool running water for at least 15 minutes

Ingestion – do not induce vomiting and give the victim plenty to drink (if conscious)

Inhalation – remove victim to fresh air. If victim is not breathing, give artificial respiration

Get medical attention in all cases

Understanding safety symbols