12
CO
2
LEVELS AND GUIDELINES
EPA Taiwan:
600ppm and 1000ppm
Type 1
indoor areas such as department
stores, theaters, restaurants, libraries,
the acceptable CO
2
concentration of 8
hours avarge is 1000ppm.
Type 2
indoor areas with special requirements
of good air quality such as schools,
hospitals, day care centers, the
suggested CO
2
level is 600ppm.
NIOSH recommendations
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, and eye/throat irritation
will be more widespread. 1000
ppm should be used as an upper
limit for indoor levels.
Non-Enforced Reference levels
Regulatory exposure limit
ASHRAE Standard 62-1989
: 1000ppm
CO
2
concentration in occupied building should
not exceed 1000ppm.
Building bulletin 101 (BB101)
:
UK standards for schools say that CO
2
at
1500ppm
averaged over the whole day(i.e. 9am to 3.30
pm) should not exceed 1500ppm.
OSHA
: 5000ppm
Time weighted average over five 8-hour work
days should not exceed 5000ppm.
Germany, Japan, Australia, UK...:
5000ppm
8 hours weighted average in occupational
exposure limit is 5000ppm.
