Hood; Warning Indicator - MSA S-Cap-Air Maintenance Manual

1.3 Regulator / cylinder valve
The regulator is mounted directly on the cylinder and has two connections. One G5/8
standard thread connection for the 200 bar compressor charging adapter, and the second
for the supply hose to the hood. The cylinder valve is part of the regulator and can be
opened and closed manually by its screw cap with the firing pin in place. For regular start-
ing the firing pin is pulled out of the screw cap and the breathing air is delivered via the
connection to the supply hose into the hood. The air outlet is the warning indicator in the
hood which is located right in the field of vision. The visual color change warning is acti-
vated at the end of service life, when the air flow diminishes and consequently the CO2
concentration rises towards the limit set down by the EN 1146. A constant reading pres-
sure indicator is fitted to the regulator permitting to read the cylinder pressure through the
bag visor.
WARNING
Do not handle the unit by the valve / regulator use carrying strap or cylinder body !
1.4

Hood

The hood assembly consists of an oro-nasal nose cup with head harness, the supply hose
with visual colour change warning, simultaneously used as air outlet and the hood with vi-
sor and flexible neck seal. The air supplied to the hood generates an air reservoir, the
breathing air is taken through the nose cup from the reservoir. The exhaled air is released
via the nose cup and the integrated exhalation valve into the ambient atmosphere. The vi-
sor offers an almost unimpaired field of vision. The warning indicator displays the effective
air flow. The elastic head harness cares for the automatic nose cup adjustment over chin,
mouth and nose. In combination with the flexible neck seal a wide variety of face sizes is
covered.
1.5 Warning indicator and duration alarm
When the end of service life is reached, the warning indicator changes slowly from
GREEN to RED warning from the reducing air flow to the hood. This is proportional to in-
creasing levels of CO from the exhalation air. The hood must then be removed.
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