Dando TERRIER Mk 1, Operating And Maintenance Manual, Page: 14 / 276

i. Both the compressor and drilling rig should be equipped with air pressure
gauges. Before commencing operations, a check should be made that these
are operative, the readings should be noted, and the main air valve checked
that it is in proper working order and can be used easily and quickly. This
valve should be of the plug cock type.
j. Hoses and fittings designed for different working pressures should be clearly
distinguished, preferably by colour coding, and should not be used at higher
pressures than that designated.
k. Hoses used for pressures in excess of 18 Bar (250p.s.i.) should be secured
to restraining anchors at each end and at suitable intervals.
l. When working above ground level air hoses should be anchored to prevent
them falling.
m. Air receivers should be marked with the safe working FA.1961 Pressure, and
be fitted with a pressure gauge and a safety valve designated to operate if
that pressure is exceeded.
n. Air receivers should be fitted with suitable drainage facilities and should be
drained off daily or more frequently if there is a high humidity level.
o. Air receivers should be thoroughly cleaned and examined at least once in
every period of twenty-six months by a competent person and a report on the
results of every such examination and test should be recorded.
p. In freezing conditions, all air exhausts and air lines being blown out should be
directed well away from workmen.
q. When air-flush drilling an extractor or hood should preferably be used at the
top of the borehole to direct air and dust away from the operators. Where
this is not practicable consideration should be given to the introduction of
foam into the air line and where this is not possible the drilling crew should
wear suitable masks and goggles.
r. Compressed air should not be used for odd jobs such as removing liquid
from, or cleaning out storage drums, nor for blowing dust from the rig unless
the air line is fitted with the correct end fitments and valves.
s. Compressed air should not be used to blow dust from wearing apparel whilst
being worn since this can cause serious injury or death by embolism in the
blood system.
t. The compressed air supply should never be cut off by kinking or bending
hoses.