Ventilation for Healthy Living
Effect of Carbon Dioxide (CO
0.04 - 0.06
Tolerable concentration when many occupants stay in the space for long time.
General tolerable concentration.
The "Building Standard Law" of Japan, "Law for Maintenance of Sanitation in Buildings" .
Tolerable concentration used for ventilation calculations.
0.2 - 0.5
0.5 or more
Long-term safety limits (U.S. Labor Sanitation) ACGIH, regulation of working offices.
Depth of breathing and inhalation volume increases 30%.
Work and physical functions deteriorate, increase breathing doubles.
Normal exhalation concentration.
The respiratory center is stimulated; depth and times of breathing increases. Dangerous if inhaled for a
4 - 5
long period. If an O
When inhaled for 10 minutes, breathing difficulties, redness in the face and headaches will occur.
Conditions will worsen when there is also an O
18 or more
Note: According to Facility Check List published by Kagekuni-sha.
1.3 Effect of Air Contamination in Buildings
Dirtiness of interior
New ceilings, walls and ornaments will turn yellow from dust in 1 to 2 years.
2. Ventilation Standards
The legal standards for ventilation differ according to each country. Please follow the standards set by your country. In the U.S.,
ASHRAE revised their standards in 1989 to become more strict.
deficiency also occurs, conditions will rapidly deteriorate and become dangerous.
Effect of Concentration Changes
There is no toxic level in
are a guideline of the
when the physical and
chemical properties of
the air deteriorate in
proportion to the
increase of CO