Hach BioTector B3500C, User Manual

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1.4.1
Ozone and Toxicity
Ozone is found in gaseous form as a natural ingredient of the earth's atmosphere. It is not a poisonous
chemical but a strong oxidizing chemical. Some of the chemical and physical properties of ozone are as
follows:
Terms Properties of Ozone (O
3
)
Molecule Weight 47.9982 g/g-mol
Boiling Point
-119

0.3 °C
Melting Point
-192.7

0.2 °C
Exposure to even low concentrations of ozone can be damaging to delicate nasal, bronchial and pulmonary
membrane. Symptoms of acute ozone toxification appear at a concentration of about 1 ppm by volume. The
type and severity of symptoms depend on the concentration and duration of exposure. In mild cases and in
the early phases of severe cases, symptoms will include one or more of the following:

Irritation or burning of the eyes, nose or throat

Lassitude

Frontal headache

Sensation of sub-sternal pressure

Constriction or oppression

Acid taste in mouth

Anorexia
In more severe cases, the symptoms may include dyspnoea, cough, choking sensation, tachycardia, vertigo,
lowering of blood pressure, severe cramping, chest pain, and generalized body pain. Pulmonary oedema may
develop with delayed onset, usually one or more hours after exposure.
Following severe acute ozone toxification, recovery is slow. In the few severe human cases reported, 10 -14
days of hospitalization were required. In these cases, minimal residual symptoms were present for as long as
9 months, but all cases eventually recovered completely.
The 1983 ACGIH has recommended a Threshold Limit Value (TLV) of 0.1 ppm (0.2 mg/m3) for ozone. The
safe level for short human exposure to concentrations of ozone in excess of 0.1 ppm (Threshold Limit Value)
is not known with certainty. The atmospheric concentration immediately hazardous to life is likewise not
known, but inhalation of 50 ppm for 30 minutes would probably be fatal. The odor threshold of ozone for a
normal person is 0.01 - 0.02 ppm by volume in air.
1.4.2 First Aid Treatment
Move the victim to an uncontaminated atmosphere. Control restlessness and pain by the administration of
sedatives and anodynes orally. Severe cases may require subcutaneous injections of small doses of
meperidine hydrochloride (Demerol) for relief of pain. Give oxygen inhalation by facemask when the acute
symptoms have subsided. Severe cases require hospitalization since deferred pulmonary oedema may
develop.