30 CFR 57.11052 - Refuge areas.
Refuge areas shall be -
(a) Of fire-resistant construction, preferably in untimbered areas of the mine;
(b) Large enough to accommodate readily the normal number of persons in the particular area of the mine;
(c) Constructed so they can be made gastight; and
(d) Provided with compressed air lines, waterlines, suitable handtools, and stopping materials.