418.1. Notwithstanding subparagraph 5 of the second paragraph of section 418, during the sinking of a shaft and the ensuing development work, the recess may be at a minimum distance of 10 m (32.8 ft) from the shaft and the working face until the progress of the work allows compliance with the requirements of subparagraph 5 of the second paragraph of section 418, in which case the quantity of explosives stored in the recess may never exceed the quantity required for one shift.