Work Environment Measurement (WEM)
Refers to the determination of environmental stresses
and their hazardous effects on worker’s health through
direct measurement of hazards using IH equipment.
Purposes of WEM
•
To evaluate the effectiveness of environmental
control measures adopted to improve the
workplace;
•
To maintain favorable environmental conditions.
•
To monitor worker’s exposure to harmful substances;
WEM Equipment
•
•
•
•
•
•
Lux Meter-Illumination
Psychrometer-Humidity
Anemometer-Air Movement
Smoke Tester
-Air Direction
Globe Thermometer-Heat
Sound Level Meter -Noise
Permissible Noise Exposure (PNE) Level
Duration/day
Hours (Hr)
8
6
4
3
2
1½
1
½
¼
Sound Level
dB (A)
90
92
95
97
100
102
105
110
115
Recommended Illumination Levels
•
•
•
•
A minimum of 50 lux – passageway, corridor,
warehouse
A minimum of 100 lux – engine and boiler rooms;
toilets and washrooms
A minimum of 200 lux – canning and preserving;
planing of lumber and veneering
A minimum of 300 lux – medium inspection; office
deskwork with intermittent reading and
writing for filing and mail sorting.
No Entry
An Oxygen Enriched
Atmosphere Exists
23.5 % O2
Entry is
Allowed
Without Respiratory Protection if:
• LEL 0%
• Benzene < 0.5 ppm
• Hydrogen Sulfide < 10 ppm
• CO < 25 PPM
• Total Hydrocarbons < 300 ppm
• Temperature < 43.3 C (110 F)
Entry with
Supplied
Breathing Air
Providing:
• LEL < 10%
• Toxic vapours below their IDLH
• Temperature < 43.3 C (110 F)
No Entry
Insufficient Oxygen to sustain
life
19.5 % O2
16.5 % O2