Engineering manual - SAB 193-233-283 S A-frame (including ATEX)
008831 en 2022.02
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3.2.13
Protecting the operator as well as the environment
Industrialisation affects our environment and it is therefore essential that we do what we can to
minimise the harmful effect on nature.
Many countries have passed legislation in an effort to reduce pollution and preserve the envi-
ronment. This legislation applies to all fields of industry, including refrigeration, and must be
complied with.
Pay extra attention to the following substances:
•
Refrigerants
•
Cooling media (brine etc.)
•
Lubricating oils
Refrigerants
usually have a natural boiling point considerably below 0° C. This means that
liquid refrigerants can be extremely harmful in contact with skin or eyes. High concentrations
of refrigerant vapours can be suffocating when they displace air. If high concentrations of re-
frigerant vapours are inhaled, they will attack the human nervous system.
When halogenated gases come into contact with open flame or hot surfaces (over approxi-
mately 300°C), they will decompose to produce poisonous chemicals. These have a very pun-
gent odour and will therefore warn personnel of their presence.
At high concentrations R717 causes respiratory problems. When the amount of ammonia va-
pour in air is between 15 and 28 vol. % the combination is explosive and can be ignited by an
electric spark or open flame.
Oil vapour in the ammonia vapour increases this risk significantly as the point of ignition falls
below that of the mixture ratio stated.
Usually the strong smell of ammonia will warn personnel before the concentration be-
comes dangerous.
The following table shows the values for the max. permissible refrigerant content in air meas-
ured in volume %. Certain countries may, however, have official limits different from the ones
stated.
Halogenated refrigerants
HFC
HCFC
Ammonia
CO
2
R134a
R404A
R407C
R507
R22
R717
R744
TWA
Time weighted aver-
age during a week
Unit
0.1
0.005
0.5
vol. %
0.1
0.1
0.1
0.1
Warning smell
vol. %
0.2
0.002