75.1714-4—Additional self-contained self-rescuers (SCSRs).
(a) Additional SCSRs in work places.
In addition to the requirements in §§ 75.1714, 75.1714-1, 75.1714-2, and 75.1714-3 of this part, the mine operator shall provide the following:
(1)
At least one additional SCSR, which provides protection for a period of one hour or longer, for each person at a fixed underground work location.
(2)
Additional SCSRs along the normal travel routes for pumpers, examiners, and other persons who do not have a fixed work location to be stored at a distance an average miner could walk in 30 minutes. The SCSR storage locations shall be determined by using one of the methods found under paragraph (c)(2) of this section.
(b) Additional SCSRs on mantrips.
If a mantrip or mobile equipment is used to enter or exit the mine, at least one additional SCSR, which provides protection for a period of one hour or longer, shall be available for each person who uses such transportation from portal to portal.
(c) Additional SCSRs in escapeways.
When each person underground cannot safely evacuate the mine within 30 minutes, the mine operator shall provide additional SCSRs stored in each required escapeway.
(1)
Each storage location shall contain at least one SCSR, which provides protection for a period of one hour or longer, for every person who will be inby that location.
(2)
Storage locations shall be spaced along each escapeway at 30-minute travel distances no greater than the distances determined by—
(i)
Calculating the distance an average miner walks in 30 minutes by using the time necessary for each miner in a sample of typical miners to walk a typical length of each escapeway; or
(ii)
Using the SCSR storage location spacing specified in the following table, except for escapeways with grades over 5 percent.
| Average entry height | Maximum distancebetween SCSR storage locations (in ft.) |
|---|---|
| <40 in. (Crawl) | 2,200 |
| >40-<50 in. (Duck Walk) | 3,300 |
| >50-<65 in. (Walk Head Bent) | 4,400 |
| >65 in. (Walk Erect) | 5,700 |
(d) Additional SCSRs in hardened rooms.
As an alternative to providing SCSR storage locations in each escapeway, the mine operator may store SCSRs in a hardened room located between adjacent escapeways.
(1)
The hardened room shall be designed and constructed to the same explosion force criteria as seals.
(2)
The hardened room shall include a means to provide independent, positive pressure ventilation from the surface during an emergency.
(3)
The District Manager shall approve the design and construction of hardened rooms in the ventilation plan.
(e) Storage location accessibility.
All SCSRs required under this section shall be stored according to the manufacturers' instructions, in conspicuous locations readily accessible by each person in the mine.
(f) Storage location signs.
A sign made of reflective material with the words “SCSRs” or “SELF-RESCUERS” shall be conspicuously posted at each storage location. Direction signs made of a reflective material shall be posted leading to each storage location.