For each of the following scenarios, select the gas exposure responsible for the signs and symptoms. A patient working with an electric arc noted a pungent odor, and now has signs of asthma or early pulmonary edema.
Answer(s): D
Ozone is a colorless, pungent gas occurring naturally in the stratosphere, which can be produced by electric arcs. Ozone is generated by electrical storms and UV light and electric arcs and some forms of fuel combustion. In the stratosphere, it is protective by blocking solar radiation. At 10 ppm, it can cause pulmonary edema and tracheal pain and is believed to cause asthma. Based on animal tests and observations of gases trapped during inversions, an action level of 10 ppm has been set for work-place exposure.
For each of the following scenarios, select the gas exposure responsible for the signs and symptoms.A sewer worker has acute onset of nausea, headache, and shortness of breath, and has anosmia.
Answer(s): C
Hydrogen sulfide is a colorless gas that rapidly paralyzes the nasal receptors, and is found in sewers.Hydrogen sulfide produces nausea, headache, and shortness of breath. Because it paralyzes the nasal receptors at a concentration of 150 ppm and cannot be smelled shortly after exposure, it is highly dangerous, with instant death from a concentration as low as 1000 ppm.
For each of the following scenarios, select the gas exposure responsible for the signs and symptoms.A man has been pulled unconscious from a mine. No odors are noted, but an experienced miner says there was coal damp in the mine.
Answer(s): B
Methane is a colorless, odorless, flammable gas sometimes encountered in mines and wells. Methane (coal damp) is a frequent cause of death in inadequately ventilated mines and wells. It acts as an asphyxiant as well as being explosive. Miners used to take caged animals, especially birds, with them. The birds succumbed to the asphyxiants (methane and carbon dioxide) sooner than humans.
For each of the following scenarios, select the gas exposure responsible for the signs and symptoms. A garage worker turns on the ventilation system in the winter time while testing a motor, and now complains of a headache and vertigo
Carbon monoxide is an odorless, colorless, tasteless gas produced by partial combustion of tobacco and fuels. The amounts produced by cigarette smoking are not insignificant. The gas combines with hemoglobin preferentially to form carboxyhemoglobin, which makes the patient appear pink. This diminishes the oxygen-carrying capacity of the blood. The resulting anoxia is the major hazard. The onset of symptoms is insidious. Individuals exposed to carbon monoxide may not voluntarily take the action necessary to remove themselves from the toxic fumes
For each of the following scenarios, select the gas exposure responsible for the signs and symptoms.Aworker drilling for oil experiences acute tearing, mucous membrane irritation, and onset of a cough while repairing machinery.
Answer(s): E
Sulfur dioxide is a colorless, pungent gas encountered in drilling for oil, paper production, treatment of fruit, and other processes. Sulfur dioxide is an irritant gas. It causes tearing, mucous membrane irritation, cough, and eventually pulmonary edema. In asthmatics it provokes bronchospasm at low doses. Like other irritant gases, in large quantities, it will damage alveoli and capillary endothelial cells.
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