Replaces the definition for two quantities in the formula of Sub-clause 22.3. Gives for Sub-clause 31.5 a new text. Adds the new Sub-clause 31.10 and 31.11. These sup-clauses contain requirements for cable penetrations and cable runs concerning the prevention of propagation of fire. Supplements Clause 32: Cable runs for essential and emergency services and Clause 41: Cables in non - metallic pipes .