Compressed Air Supply; Compressed Air Cylinders; Dsg Or Mass Pressure Reducer With Warning Signal - MSA DSL Serie Manual De Instrucciones

4.

Compressed Air Supply

Important!
The breathable air must conform to EN 12021. Excessive levels of humidity in the breathing
air at temperatures below 4°C can cause the apparatus to malfunction (due to freezing)! Use
a water separator if necessary.
The use of oxygen or oxygen-enriched air is not allowed.
4.1.

Compressed Air Cylinders

Breathable air can be supplied from compressed air cylinders with a DSG or MASS pressure reducer. For
suitable cylinders see ordering information in section 12
When using compressed air cylinders pay attention to the following:
 Only use compressed air cylinders which have been type-tested and approved for the related working
pressures for breathable air as defined in EN 12021.
 Care should be taken when handling cylinders, never carry by the hand wheel, always disconnect before
transport and always secure cylinders not in use so they cannot move
The cylinder valves screwed into the compressed air cylinders must be in accordance with EN 144 standard

with a G 5/8 side fitting.
 Before starting any use the operator should check that cylinders are adequately filled to carry out the activity.
 An assistant should be always available in the proximity of a cylinder supplied system, in permeant contact
with the user, to inform the users about activation of warning signals and carry out any operations necessary
for the correct performance of the device
External icing may occur on the cylinder valve, pressure reducing valve and coupling, depending on the
temperature, but this has no effect on the equipment function. However, completely empty cylinders should be
dried, this is necessary to avoid the formation of condensation inside cylinders. They can be dried, for example,
after being recharged twice at operating pressure with dry compressed air coming from a suitable compressor
and then depressurized slowly.
4.2.

DSG or MASS Pressure Reducer with Warning signal

The pressure reducers are designed for a working pressure of 300 bar, but can of course also be operated with
an upstream pressure of 200 bar. The pressure reducer is made of brass. At the pressure reducer is a safety
valve, an audible warning signal, a high pressure gauge line and a medium pressure gauge.
The look-out person or safety officer can observe on the medium pressure gauge whether the wearer of the
apparatus is breathing regularly, for example if the wearer is working inside a tank and is no longer visible to the
observer, and can also notice in time whether the warning signal has been activated. The medium pressure is
fixed so that the pressure reducer reduces the cylinder pressure to around 7 bar.
The integrated safety valve is set to respond if the pressure rises above 12 bar.
The warning signal is set to be activated and emit an audible warning signal at a minimum cylinder pressure of 30
bar. The signal sounds until the usable air supply is almost exhausted. The warning whistle operates without an
injector, i.e. no external air is required to generate the audible signal. This ensures that it will function even in high
humidity or if external moisture is present, and in temperatures below freezing point.
DSL Series
Compressed Air Supply
13
GB