PD 6662: intruder alarm grades and standards in the UK, explained
Reviewed by the SPS Technical team · Last checked 12 October 2026
Quick answer
PD 6662:2017 is the scheme that applies the European intruder alarm standards (the BS EN 50131 series) in the UK. It sets how a system is graded from 1 to 4 by risk, which other British Standards apply alongside it, and is the standard police and insurers expect a monitored intruder alarm to meet.
What it means for you
- Your intruder alarm should be designed to a security grade matched to your risk, usually Grade 2 or 3 for businesses.
- Every part of the system should be at least the grade of the system as a whole.
- If you want police response, the system must be installed and maintained to PD 6662 by a certified company.
- Ask for a certificate that states the grade and the standards the system meets.
Who it applies to
Anyone installing, maintaining or relying on an intruder or hold-up alarm in the UK, particularly where insurers or the police require a certified, graded system.
Common questions
What grade of intruder alarm do I need?
It depends on your risk. Grade 1 is low risk, Grade 2 suits most homes and many small businesses, Grade 3 is typical for higher-value commercial premises and Grade 4 is for very high-risk sites. Your insurer may specify a grade.
Is PD 6662 needed for police response?
Yes. The police policy for security systems requires monitored intruder alarms to be installed and maintained to PD 6662 by a company certified to do so.
Official sources
This page is a plain-English summary, not a copy of the standard. British Standards are copyright of BSI.
Reviewed by the SPS Technical team · Last updated October 2026