PN 0467 BA Sub-Surface Procedure

Question 1

Incidents at extensive sub-surface premises where there is no evidence of unsafe conditions at surface level may require the implementation of special procedures that allow:

Answer 1

• A reconnaissance team wearing BA (not started up) to be committed
• BA ECP to be set up at a bridgehead within the premises

Question 2

In recognition of the inherent risks attached to sub-surface incidents, the following principles should be followed:

Answer 2

• Only implemented when there is no evidence of unsafe conditions at surface level
• Should not be adopted at sewer incidents or where unseen toxic gases may be expected
• All personnel proceeding below surface level must be equipped with BA and operate in teams of two until IC decides BA not required
• Record of all personnel working below surface kept at surface level