Product: Ozone Test Strips
AND THEIR EFFECTS
Data from IOA
Edited by D. R.
Parts per million volume air concentration
Lowest value detectable by hypersensitive humans. Too low to measure accurately
with elaborate electronic equipment.
Threshold of odor perception in laboratory environment, 50 per cent confidence
to 0.010 ppm
The threshold of odor perception by the average person in clean air. Readily
detectable by most normal persons. These concentrations can be measured with
fair accuracy. Ozone levels measured in typical residences and offices equipped
with a properly operating electronic air cleaner when outdoor ozone level is
low. Infiltrating outdoor ozone could cause higher indoor concentrations.
Threshold of odor perception in laboratory environment, 90 per cent confidence
Typical ozone concentrations found in the natural atmosphere. These levels
of concentration vary with altitude, atmospheric conditions and locale.
Representative average total oxidant concentrations in some major cities in
1964. Approximately 95 per cent or greater of these oxidants are generally
accepted to be ozone.
CSA maximum limit for devices for household use. Measured as sustained concentration
in test room.
Maximum allowable ozone concentration recommended by ASHRAE in an air conditioned
and ventilated space.
Maximum ozone concentration produced by electronic air cleaners and similar
residential devices according to the proposed amendment of the Federal
Food, Drug and Cosmetic Act.
Proposed national ambient air quality standards for photochemical oxidants
(maximum 1 hour concentration not to be exceeded more than once per year).
The maximum allowable ozone concentration in industrial working areas: permissible
human exposure - 8 hours per day, 6 days a week.
Continuous maximum ozone concentration allowable (per U.S. Navy_ in confined
quarters such as atomic submarines.
Maximum allowable limit for industrial, public, or occupied spaces in England,
Japan, France, the Netherlands and Germany.
Typical peak concentrations in American cities.
Prolonged exposure of humans under occupational and experimental conditions
produced no apparent ill effects. The threshold level at which nasal and
throat irritation will result appears to be about 0.300 ppm.
The ozone level at which some species of plant life began to show signs of
ozone effects. Foliage injury appears as dark stipples, light flecks, dead
patches and general discoloration. The stomata (pores) of adult leaves
are the first areas to show signs of damage.
The ozone level at which Los Angeles, California, declares its Smog Alert No.
1. Can cause nausea and headaches in some individuals. Extended exposure
could cause lung edema (an abnormal accumulation of serous fluid in connective
tissue or serous cavity). Enhances the susceptibility to respiratory infections.
Los Angeles, California, declares its Smog Alert No. 2 at 1.00 ppm ozone concentration
and Smog Alert No. 3 at 1.500 ppm. When this range of ozone concentration was
inhaled by human volunteers for 2 hours, it caused symptoms which could be
tolerated without incapacitation with the symptoms subsiding after a few days.
The symptoms were headache, pain in the chest, and dryness of the respiratory
The pinto bean exposed to 1.4 to 5.0 ppm ozone concentrations for 70 minutes
showed some signs of severe injury to mature leaves.
Experimentation showed that a 3 hour exposure at 12 ppm was lethal for Guinea
pigs. Welders who were exposed to 9 ppm concentration plus other air pollutants
developed pulmonary edema. Chest X-rays were normal in 2 to 3 weeks, but 9
months later they still complained of fatigue and exertional dyspnea (labored
Ozone concentrations that are immediately hazardous to human life are unknown
but on the basis of animal experimentation, and exposure at 50 ppm concentration
for 60 minutes would probably be fatal.