How often should a fire alarm be serviced?
Every 6 months
Government guidance states that fire alarms should be installed in accordance with British Standard BS 5839, which in turn recommends that your detection and warning systems should be inspected by a 'competent person' at least twice a year.
Such an inspection could be carried out in two ways - either as part of a full Fire Risk Assessment (required by law), or during a dedicated fire alarm check survey. Both options will leave you with a documented report to show the relevant bodies and your local fire service that you are meeting the recommended servicing/testing schedule above, and will also ensure you are meeting the Regulatory Reform Order (Fire Safety) 2005 guidance that your critical fire equipment is checked and maintained by the 'competent person' required where you might not have the time, knowledge or confidence to complete the necessary audits.
If you are the Responsible Person for larger premises, or if your business is being disrupted by Coronavirus closures, it's a good idea to arrange more regular fire alarm checks, ideally on a quarterly basis.