Non-Combustible Linings

(4) Except for in a fire-isolated exit, services or equipment enclosed in accordance with (5) may be installed in a required exit, or in any corridor, hallway, lobby or the like leading to a required exit, where that service or equipment comprises—

• a) electricity meters, distribution boards or ducts; or
• b) central telecommunications distribution boards or equipment; or
• c) electrical motors or other motors serving equipment in the building.

(5) An enclosure for the purposes of (4) must be suitably sealed against smoke spreading from the enclosure and be—

• a) non-combustible construction; or
• b) a fire-protective covering.

Services or equipment comprising-

• (i) electricity meters, distribution boards or ducts; or
• (ii) central telecommunications distribution boards or equipment; or
• (iii) electrical motors or other motors serving equipment in the building,
  may be installed in-
• (iv) a required exit, except for specified fire-isolated exits; or
• (v) in any corridor, hallway, lobby or the like leading to a required exit,

if the services or equipment are enclosed by non-combustible construction or a fire-protective covering with doorways or openings suitably sealed against smoke spreading from the enclosure.

Services or equipment comprising-

• (i) electricity meters, distribution boards or ducts; or
• (ii) central telecommunications distribution boards or equipment; or
• (iii) electrical motors or other motors serving equipment in the building,
  may be installed in-
• (iv) a required exit, except for specified fire-isolated exits; or
• (v) in any corridor, hallway, lobby or the like leading to a required exit,

if the services or equipment are enclosed by non-combustible construction or a fire-protective covering with doorways or openings suitably sealed against smoke spreading from the enclosure.

Services or equipment must not be installed in a required exit or in any corridor, hallway, lobby or the like leading to a required exit if it comprises

• (i) electricity meters, distribution boards or ducts; or
• (ii) central telecommunications distribution boards or equipment; or
• (iii) electrical motors or other motors serving equipment in the building,

unless it is enclosed by non-combustible construction or a fire-protective covering with doorways or openings suitably sealed against smoke spreading from the enclosure.