2. The National ambient air quality standard for sulfur dioxide is 180 µg/m3. Assuming a lifetime exposure (24 hr/day, 365 days/year) for an adult male of average body weight. What is the estimated lifetime CDI for this concentration? Assume the exposure duration equals the lifetime.

The total mercury concentration in the San Francisco Bay Area is reported to be 2.1 mg/m3 in air. Report this concentration in ppmv. Assume the air temperature is 20oC.

The recommended threshold limit value (TLV-ACGIH) air concentration for occupational exposure to water-insoluble hexavalent chromium Cr (VI) is 0.01 mg/M3. This concentration assumes that the individual is generally healthy and is exposed for 8 hours per day 5 days per week (40 hour work week) over a working lifetime (that is from age 18 to 65 years). Assuming a body weight of 75 kg and an inhalation rate of 0.85 m3/h over the working life of the individual, a. What is the lifetime (75 y) CDI? b. Estimate the low-dose cancer risk from occupational inhalation exposure to hexavalent chromium Cr(VI).

Environmental Engineering The air quality standard for ozone (O3) is 80 ppbv. Express that standard in micrograms per cubic meter at 1 atm pressure and 25oC. At the elevation of Denver, the pressure is 0.82 atm. Express the sulfur dioxide standard at that pressure and a temperature of 15oC.