Security grade

A classification under BS EN 50131 describing the capability of intruder a system is designed to resist, from Grade 1 (low risk, unskilled intruder) to Grade 4 (high risk, planned attack with specialist equipment). Most UK homes are specified at Grade 2, most commercial premises at Grade 2 or 3.

Also written: grade 1, grade 2, grade 3, grade 4, alarm grade.