---
kind: "section"
citation: "30 C.F.R. § 7.503"
title: "30"
number: "7.503"
heading: "Application requirements."
url: "https://uscodex.org/cfr/30/7.503"
---

# §7.503. Application requirements.

- (a) An application for approval of a refuge alternative or component shall include:
  - (1) **The refuge alternative's or component's make and model number, if applicable.**
  - (2) **A list of the refuge alternative's or component's parts that includes—**
    - (i) The MSHA approval number for electric-powered equipment;
    - (ii) Each component's or part's in-mine shelf life, service life, and recommended replacement schedule;
    - (iii) Materials that have a potential to ignite used in each component or part with their MSHA approval number; and
    - (iv) A statement that the component or part is compatible with other components and, upon replacement, is equivalent to the original component or part.
  - (3) The capacity and duration (the number of persons it is designed to maintain and for how long) of the refuge alternative or component on a per-person per-hour basis.
  - (4) **The length, width, and height of the space required for storage of each component.**
- (b) The application for approval of the refuge alternative shall include the following:
  - (1) A description of the breathable air component, including drawings, air-supply sources, piping, regulators, and controls.
  - (2) The maximum volume, excluding the airlock; the dimensions of floor space and volume provided for each person using the refuge alternative; and the floor space and volume of the airlock.
  - (3) The maximum positive pressures in the interior space and the airlock and a description of the means used to limit or control the positive pressure.
  - (4) The maximum allowable apparent temperature of the interior space and the airlock and the means to control the apparent temperature.
  - (5) The maximum mine air temperature under which the refuge alternative is designed to operate when the unit is fully occupied.
  - (6) Drawings that show the features of each component and contain sufficient information to document compliance with the technical requirements.
  - (7) A manual that contains sufficient detail for each refuge alternative or component addressing in-mine transportation, operation, and maintenance of the unit.
  - (8) **A summary of the procedures for deploying refuge alternatives.**
  - (9) **A summary of the procedures for using the refuge alternative.**
  - (10) **The results of inspections, evaluations, calculations, and tests conducted under this subpart.**
- (c) The application for approval of the air-monitoring component shall specify the following:
  - (1) The operating range, type of sensor, gas or gases measured, and environmental limitations, including the cross-sensitivity to other gases, of each detector or device in the air-monitoring component.
  - (2) The procedure for operation of the individual devices so that they function as necessary to test gas concentrations over a 96-hour period.
  - (3) **The procedures for monitoring and maintaining breathable air in the airlock, before and after purging.**
  - (4) The instructions for determining the quality of the atmosphere in the airlock and refuge alternative interior and a means to maintain breathable air in the airlock.
- (d) The application for approval of the harmful gas removal component shall specify the following:
  - (1) The volume of breathable air available for removing harmful gas both at start-up and while persons enter through the airlock.
  - (2) The maximum volume of each gas that the component is designed to remove on a per-person per-hour basis.

## Notes

### Source

Source: 74 FR 80694, Dec. 31, 2008, unless otherwise noted.

### Authority

Authority: 30 U.S.C. 957.

### Source

Source: 53 FR 23500, June 22, 1988, unless otherwise noted.