You must always refer to your ships SMS/maintenance system and manufacturers instructions for equipment specific instructions on recharging. The following is intended as a generic guide only.
Recharging fire extinguishers
Water
- Ensure that there is no residual pressure
- Unscrew the head assembly not more than one third of the whole way in case any residual pressure exists despite your checks.
- Note the liquid level and pour the liquid into a clean container
- Examine the external and internal condition of the body for corrosion or damage
- Measure the weight of the empty body and compare it with the mass noted on the cartridge
- Examine – and clean if required – the vent holes in the cap
- Examine the nozzle, strainer and internal discharge tube, clean them as necessary and check that there are no blockages
- Check the operating mechanism and clean them if necessary
- Check the condition of the sealing washers and hose – replace if the parts are not in good condition
- Return the original charge back into the extinguisher and top up to the required level with fresh water
- Refit the safety pin
Foam
Foam extinguishers are inspected the same as water extinguishers except that the foam solution replaces some of the water charge.
Generally the foam solution needs replacing every four years but atmospheric conditions will affect its life. This will be evidenced by a hydrogen sulphide smell or the solution being black rather than brown.
Dry Powder
The extinguisher should be weighed and checked against the recorded weight when it was first put into service. If there is a weight loss of greater than 10 per cent, then the extinguisher should be recharged.
Dry powder extinguishers should only be opened up in the driest conditions and for the shortest time needed as the powder will absorb moisture. Different types of powder should not be mixed as a chemical reaction can take place which produces CO2 and water which leads to ‘caking’ and a dangerous rise in pressure.
During the inspection, the powder should be checked for ‘caking’, lumps or foreign bodies. The cap should be replaced, and the powder agitated by inverting and shaking the extinguisher body.
Wet Chemical and CO2
These are not normally recharged on ship and each shipping company will arrange for the extinguishers to be recharged by a shore based provider.
