FINAL DRAFT prEN 14931

prEN 14931:2006 (E)
4.6 Compressed air supply system
4.6.1
The air supplied to the pressure chamber shall conform at least to the purity requirements specified in EN 12021.
Testing:
Checking compliance with the test protocol.
4.6.2
A compressed-air supply system comprises at least two sources of compressed air for operation and emergency
supply. One of these sources shall be a compressed air container.
4.6.3
The compressed-air supply system shall be capable of providing sufficient compressed air:
a) to increase of pressure in the main chamber once from ambient pressure to maximum operational pressure
with a maximum compression rate according to 4.3.1;
b) to increase of pressure in the ante chamber twice from ambient pressure to maximum operational pressure;
c) to maintain 200 kPa (2 bar) in the main chamber at an air-change rate of 30 l/min per person x absolute
pressure (measured decompressed) for at least 150 min for the maximum allowable number of occupants in
the main chamber according to 4.3.3;
d) in addition, for pressure chambers with a maximum operational pressure greater than 200 kPa (2 bar), to
maintain the maximum operational pressure in the main chamber at an air-change rate of 30 l/min per
person x absolute pressure (measured decompressed) for at least 60 min for three persons;
e) at the end of each treatment it shall be possible to treat a patient at 200 kPa (2 bar) for 5 h at least.
Testing:
The quantity of air required for cases a) to d) is to be calculated. Subsequently it is to be checked by inspection
whether the air supply system provided is capable of supplying the total quantity of air required.
A tightness test of the overall compressed-air system is to be performed at 100 % of the maximum allowable working
pressure to be expected at the respective location (test medium: compressed air) and tightness is to be certified. A
system is considered to be sufficiently tight if during a period of 10 min the pressure in the individual compressed-air
subsystems has not dropped by more than 1 %.
4.6.4
If multiple compressors are used they shall be independent of each other.
4.6.5
At least 50 % of the total quantity of air calculated in accordance with 4.6.3 shall be available as compressed air
supply in compressed air containers.
Testing:
It is to be checked whether the air supply system provided meets the requirements stipulated. To this effect the
capacity of the compressed air containers provided is to be determined on the basis of the data stated on them.
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