Program Policy Manual - VOLUME V - Mine Safety and Health ...

MSHA PROGRAM POLICY MANUAL VOLUME V
When machines are mechanically connected to each other but trammed
independently, and are sufficiently different in size, weight, and
power, an emergency stop switch shall be installed on the smaller
machine to deenergize the larger machine. Without an emergency
stop switch the equipment is not considered to be in a safe
operating condition and must be removed from service.
75.1729 Welding Operations
Welding operations shall be shielded to the extent that the other
persons working in the adjacent area will not be able to view the
welding area directly. Areas in which welding operations are
being performed shall be ventilated sufficiently to prevent
accumulation of smoke and other contaminants.
75.1730 Compressed Air; General; Compressed Air Systems
All pressure vessels shall be plainly marked with the
manufacturer's name and maximum allowable working pressure.
Safety relief valves shall be adjusted to flow at a pressure not
exceeding the maximum allowable working pressure of the vessel,
except that if the vessel is exposed to fire or other sources of
external heat the relief valve may be adjusted to a value not
exceeding 110 percent of maximum allowable working pressure.
February 2003 (Release V-33) 160