MetFab - Welding Fume Handbook - Flipbook - Page 15
5 Exposure limits in the UK
and are used for substances or
concentrations causing acute harmful
effects. Many substances have both an
LTEL and an STEL, the latter being the
higher value.
Table 2 gives UK OELs for substances
likely to be found in welding fume. Each
component of the fume has its own
OELs, but welding fume as a "substance"
in its own right also has an OEL. Control
of gases and fume must be such that
exposure does not exceed either the OEL
for any component of the fume, nor for
the fume as a whole.
Substance
Type of limit
LTEL (8-hour TWA) STEL (15-min TWA)
(mg/m³)
(mg/m³)
Welding fume
OES
5
Iron oxide fume (as Fe)
OES
5
10
Zinc oxide fume
OES
5
10
Manganese fume (as Mn)
OES
1
3
Chromium III compounds (as Cr)
OES
0.5
Chromium IV compounds (as Cr)
OES
0.05
Nickel (insoluble compounds)
OES
0.5
Copper fume
OES
0.2
Ozone
OES
0.2 ppm
Nitrogen monoxide
OES
25 ppm
35 ppm
Nitrogen dioxide
OES
3 ppm
5 ppm
Carbon monoxide
OES
50 ppm
300 ppm
Table 2: UK occupational exposure limits for substances likely to be found in welding fume.
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