This is a decision for the Fire Risk Assessor and Fire Risk Assessment and the answer varies for each individual property.

Two very similar properties could have different requirements for fire extinguishers based on their internal layout, use (i.e. Office or Storage), the materials in the property, the Fire Evacuation Policy and even the occupant's use of the building. There is no "general rule of thumb" as such when it comes to extinguisher requirements that suit all buildings.

If you are unsure, you should always refer to your Fire Risk Assessment.

We often find that the importance of fire extinguishers can be undervalued and or overlooked. Fire extinguisher maintenance can help to prevent fires from spreading and can also help to save lives in the event of a fire.

If a small fire broke out in your building one of the first reactions is to look for an extinguisher to help either prevent the spread of fire or to help you escape.

The only way you can be confident that your extinguishers will work if needed is regular maintenance (in line with suitable training on their use) and that why servicing is vital. 

A unit that has not been maintained regularly could fail to work correctly or not at all. The last place you want to find this out is when you are trying to fight a fire. 

Please Note: Unless you are trained in the operation of Fire Extinguisher it is not recommended they are used.

Under the requirements of BS5306-3:2017, fire extinguishers should have a 12-monthly basic service. 

In addition to the annual service, extended services should be completed:

• Every 5 years for water-based & Powder Units.

Overhauls should be completed:

• Every 10 years for CO2, clean agent & halon units.

At the end of the service, a Fire Extinguisher Service Inspection report is provided.
This document details the service works completed, any failures or non-compliances including advising you of any necessary action to ensure your extinguishers are in working order.

AVA Fire and Secuirty, also create an asset register, which details the location, type & test results of each individual extinguisher which is available upon request.

All extinguishers should be subject to a commissioning process on initial installation at the location the unit is being installed. 

It is a common misconception that new extinguishers, when purchased from an online store or picked up from a shop, are ready for use.

Commissioning cannot be done prior to the extinguisher being placed in property in the location they are to be used. This must be completed by a competent person, as defined by the British Standard.

After commissioning, the unit should then be serviced on an annual basis.