Alarm systems are graded 1-4 and only grades 2 and 3 are usually installed in this country by professional installers.
Grades are based on the resilience to attack of the system and Insurance companies will usually specify what grade
is required the grades are determined as follows: -
Grade 1-Low Risk
Intruders are expected to have little knowledge or tools to compromise the system. Garde 1 systems are not installed by
accredited installing companies.
Grade 2 - Low-Medium Risk
Thieves are expected to have an interest as the property will have items of significant value, therefore intruders are expected to have limited knowledge and tools to compromise the system. Remote monitoring of the system is an option, certain build quality is enforced along with design requirements such as 500 event memory logs.
Typical installations are residential and low to medium risk commercial properties.
Grade 3 - Medium-High Risk
Thieves are expected to have a high interest as the property will have items of high value, therefore intruders are expected to have knowledge and a full range of tools to compromise the system. Remote monitoring should be installed and have 2 paths of signalling, normally one by landline and the other by radio for back up. Detection should be able to pick up masking or covering of the unit.
Typical installations are higher risk commercial properties e.g. banks, jewellery shops, steel stockholders, mobile phone
shops.
Grade 4 - High Risk
Thieves are expected to have a high interest in the property and are likely to be sophisticated in their planning of attack and theft, they would be expected to fully plan any intrusion and are expected to have sophisticated knowledge and tools to compromise the system. Similarities with grades 3 systems are in place and in addition detectors should be able to sense a reduction in range of the detector.
With the exception of the signalling equipment which is grade 4 there is very little grade 4 equipment manufactured and
for high risk premises insurers often specify grade 3.