UEi Test Instruments AQM4 - Manual (Page 25)

REGULATORY EXPOSURE LIMIT
ASHRAE Standard 62.1-2004:
CO² concentration in occupied building
should not exceed 1000ppm.
Building Bulletin 101 (BB101): 1500ppm
UK standards for schools state that CO²
averaged over the whole day (i.e. 9am to
3:30pm) should not exceed 1500ppm.
OSHA: 5000ppm
Time weighted average over five 8-hour
work days should not exceed 5000ppm.
Mak: Germany, Japan, Australia, UK:
5000ppm
Eight hours weighted average in
occupational exposure limit is 5000ppm.
(See Ashrae 62.1-2004 Table B-1)
NON-ENFORCED REFERENCE LEVELS
NIOSH Recommends
250-350ppm: normal outdoor ambient
concentrations
600ppm: minimal air quality complaints
600 - 1000ppm: less clearly interpreted
1000ppm: indicates inadequate ventilation;
complaints such as headaches, fatigue, eye/
throat irritation will be more widespread.
1000ppm should be used as an maximum
limit for indoor levels.
CO² LEVELS AND GUIDELINES
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