27-411. Definitions

In this article, unless the context otherwise requires:

1. "Dust prevention practices" includes ventilation, suction or exhaust methods of removing dust, wet methods for settling dust, and the use of respirators when the condition or exposure is temporary or intermittent, and other means of removing or settling dust from mine air as approved by the state mine inspector.

2. A "hazardous dust or gas condition" shall exist when the breathing zone of an employee while engaged in the performance of his work contains higher concentration limits of toxic dust and fumes, mineral dusts, and gases than specified by the state mine inspector in the rules and regulations. Dust counts shall be determined in accordance with techniques prescribed by the inspector and shall be made when necessary.

3. "Respirators" means only those respirators approved by the United States bureau of mines or which may be approved hereafter by the United States bureau of mines and by the state mine inspector.

4. "Breathing zone", in the case of persons wearing respirators, is the air space created after the passage of air through the protective device.