TABLE OF LOWER EXPLOSIVE LIMITS - L.E.L.
The figures quoted below are taken from British Standards Institute publication BS 5354
Part 1: 1976 and show the L.E.L. of some of the more common gases and vapours:
GAS L.E.L. % VOLUME
Acetone ...................................................................................... 2.1
Ammonia ....................................................................................15.0
Benzene ...................................................................................... 1.2
n-Butane ..................................................................................... 1.5
Carbon monoxide .......................................................................12.5
Ethylene ...................................................................................... 2.7
Heptane...................................................................................... 1.1
Hexane ....................................................................................... 1.2
Hydrogen.................................................................................... 4.0
Methane ..................................................................................... 5.0
Propane ...................................................................................... 2.0
Pentane....................................................................................... 1.4
Toluene ....................................................................................... 1.2
Xylene......................................................................................... 1.0
TABLE OF OCCUPATIONAL EXPOSURE LIMITS - P.P.M.
The figures quoted below are taken from guidance note EH40 from the Health and Safety
Executive.
GAS 8 HOUR - T.W.A. - P.P.M.
Hydrogen sulphide ...................................................................... 10
Carbon monoxide ....................................................................... 30
Sulphur dioxide ........................................................................... 2
Nitrogen monoxide...................................................................... 25
Nitrogen dioxide.......................................................................... 3
Chlorine......................................................................................0.5
Ammonia .................................................................................... 25
Ozone ........................................................................................0.1
Ethylene oxide ............................................................................. 5
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