Technical Booklet E Fire Safety·Page 125·4.48 Note 2
Casing specification for compartment penetrations
Casings around pipes penetrating compartment elements must be imperforate except for pipe openings and access panels, must not be sheet metal, and must provide not less than 30 minutes fire resistance.
The casing should –
(a) be imperforate except for an opening for a pipe or an access panel;
(b) not be of sheet metal; and
(c) have (including any access panel) not less than 30 minutes fire resistance.
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