BS5839 system categories

[TickityBoo]

Easy question for somebody - when did the definitions for the categories last change?  Was it 1980 / 88?  I remember that an L3 used to be escape routes only but changed to include rooms off escape routes as well as the escape routes.  L4 then took over from L3 and assumed the escape route only definition. 

[kurnal]

1988 version had a note in the explanatory text that L3 should include the rooms off escape routes but it could easily be missed or misinterpreted.

2002 introduced L4 and L5 and became explicit that L3 included rooms off escape routes.

[colin todd]

L3 was invented, along with other "types" (now "categories") of system in 1988. It was also made pretty clear that L3 needed detection in rooms off escape routes- that was the whole reason it was invented.