239Location of misfire

239 Location of misfire After the end of the period that applies under section 237, the shot-firer must— (a) thoroughly examine the blasting site and do any work that is necessary to work out the location of any misfire and its cause; and (b) carefully search for, collect, and safely dispose of any unexploded explosive or debris likely to contain explosive that is on the surface; and (c) warn all incoming work crews of the possible presence of explosives in any broken ground or rock.