Unit IV Assessment

1. Ammonia is a colorless gas that is easily recognized because of its pungent odor. Ammonia is often encountered as anhydrous ammonia. Describe anhydrous ammonia and at least three of its commercial uses. When there is a release, explain why emergency responders should not apply water directly to the release of aqueous ammonia. Provide its chemical reaction with water.

Your response must be at least 75 words in length.

2. In the biological treatment of wastewater, microorganisms break down the organic matter, such as food, oil, and human waste, in the wastewater and forms CO2 and microbial biomass. When firefighters combat a fire near a wastewater treatment plant where agricultural pesticides are involved, explain why the wastewater treatment operators are notified. Also, explain why there are fewer inorganic pesticides that are encountered today.

Your response must be at least 75 words in length.

3. The 8-hour time-weighted average limit set by the Occupational Safety and Health Administration (OSHA) for carbon monoxide (CO) is 50 ppm. The OSHA regulation at 29 C.F.R. 1910.1000(d) requires employers to determine the cumulative exposure of workers to certain gases over an 8-hour work shift using the formula below.

Formula to determine cumulative exposure of workers to certain gases

Where:

E = equivalent exposure for the work shift
C = concentration during any period of time in which the concentration remains constant
T = duration of time in hours of the exposure

The regulation further stipulates that no employee can be further exposed to the gas when the value of E exceeds the 8-hour time-weighted average limit set for the given substance. Using the formula above, determine if the employer complied with this regulation if a worker is exposed to CO concentrations throughout the workday as follows: 45 ppm for 3.25 hours; 75 ppm for 2.5 hours; 50 ppm for 1.5 hours and 60 ppm for 45 minutes. Explain CO poisoning and the interaction of CO with hemoglobin.

Please show your exposure calculation, not just your calculated answer. Your response must be at least 75 words in length.