Industrial Hygiene unit VIII

Question 1

You are an industrial hygienist conducting personal sampling on a worker who is overseeing a production process involving use of acetone (Note: The Occupational Safety and Health Administration has established a Permissible Exposure Limit of 1000 parts per million (ppm) of acetone). You are able to measure the following exposures:

700 ppm for 3 hours

1300 ppm for 2 hours

900 ppm for 3 hours

What is the calculated TWA? What would you tell plant management in terms of exposure to acetone and compliance with the PEL?

• there is a 200 word minimum response required.
• Credible reference materials, including your course textbook(s), may be used to complete the assessment. 

Question 2

Please solve the following problem, indicating your response on a Word document and submitting the document via File Upload.

Using the following formula, solve the problem below, and show your work.

TWA = CaTa + CbTb + ... + CnTn

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TWA      =             Time-Weighted Average

Ca           =             Concentration of contaminant during the sampling period "a"

Ta           =             Time of sampling period "a"

Cb           =             Concentration of contaminant during the sampling period "b"

Tb           =             Time of sampling period "b"

Cn           =             Concentration of contaminant during the sampling period "n", where "n" is the last of a series of contaminants

Tn           =             Time of sampling period "n"

Note: All concentrations are in parts contaminant per million parts of air or milligrams of contaminant per cubic meter of air.

Air Sampling Problem: You are an industrial hygienist that is conducting personal sampling on a worker who is overseeing a production process involving use of toluene (Note: The Occupational Safety and Health Administration has established a Permissible Exposure Limit of 200 parts per million (ppm)). You are able to measure the following exposures:

500 ppm for 1 hour

100 ppm for 4 hours

225 ppm for 3 hours

What is the calculated TWA? What would you tell plant management in terms of exposure to toluene and compliance with the PEL?

• there is a 200 word minimum response required.
• Credible reference materials, including your course textbook(s), may be used to complete the assessment.