Fire Alarm category L2 design - (19 e)

In a Category L2 wired fire alarm system,or a wireless fire alarm the rooms or areas protected should comply with the recommendations for a Category L3 system, but, in addition, automatic fire detection should be installed in rooms in which the fire risk is high enough to warrant individual fire protection.

NOTE 6 Any reference to a Category L2 system (e.g. in a specification, proposal or submission to an enforcing authority) should
clearly identify the rooms or areas in which these additional detectors are to be installed and should identify the type of detector
(e.g. heat, smoke or combustion gas) required.

f) In a Category L1 or P1 fire alarm system or a wireless fire alarm, automatic fire detectors should be installed in all rooms and areas of the building, but the following rooms or areas need not be protected if they are of low fire risk — toilets, shower rooms and bathrooms;
NOTE 7 In some public buildings, such as hospitals and shopping centres, toilets might not be of low fire risk, owing to the
potential for arson.
— stairway, lobbies" and toilet lobbies;
— small cupboards (typically, less than 1 m2);

NOTE 8 A riser in which there is a fire resisting floor and ceiling may be treated as a cupboard.
— some shallow voids (less than 800 mm in depth).
g) In a Category L1 fire alarm system or a wireless fire alarm, the detectors within escape routes should be smoke detectors, or fire detection. In a Category P2 fire system, the rooms or areas to be protected by automatic fire detection should be clearly identified in the specification or proposal. There should be physical barriers between protected and unprotected areas to limit the spread of smoke and hot gases in, at least, the early stages of fire.

NOTE 9 It is not necessarily the case that these physical barriers should have a recognized period of fire resistance.
NOTE 10 The physical barriers described above might be unnecessary where detectors are installed to detect fires in specific
equipment.