In addition to the safety rating, each component has an environmental classification. There are no general environmental ratings. Each component must meet the classification for the location in which it will be installed. These environmental classes are defined as follows:
CLASS 1
Indoor
Environmental influences normally experienced indoors when the temperature is well maintained, e.g. in a residence or commercial property.
CLASS 2
General Indoor
Environmental influences normally experienced indoors when the temperature is not well maintained, e.g. corridors, halls, stairwells or when condensation may occur on windows, in unheated storage areas or in warehouses where heating is intermittent.
CLASS 3 - Outdoor
Covered / Indoor Extreme
The intruder is expected to be knowledgeable about intrusion alarm systems and have an extensive range of tools such as frequency jammers and portable electronic equipment.
CLASS 4
Outdoor
Environmental influences normally experienced outdoors when intrusion alarm system components are fully exposed to the weather.
For most alarm systems, all interior components shall be Class 2 (Indoor-General) with a Class 4 (Outdoor General) outdoor siren. Class 3 (Outdoor Covered or Indoor Extreme Conditions) components shall be required if the alarm system includes barns or sheds exposed to weather.