Air Pollution Measurements and Estimates

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What is the main objective of ambient measurement in air pollution?

To measure the concentration of pollutants from a specific source
To evaluate the effectiveness of air pollution control devices
To determine whether the air is safe to breathe (correct)
To regulate the time and amount of emission from a source

What is the primary purpose of source measurement in air pollution?

To determine whether the air is safe to breathe
To measure the concentration of pollutants in the ambient air
To evaluate the effectiveness of air pollution control devices
To regulate the time and amount of emission from a source (correct)

Why are measurements necessary in air pollution control?

Only for legal requirements
Only for evaluation of air pollution control devices
To determine the concentration of pollutants in the ambient air
For both legal requirements and evaluation of air pollution control devices (correct)

What is the primary requirement of a sampling system in air pollution measurement?

To obtain a sample that is representative of the atmosphere at a particular place and time (A) Signup and view all the answers

What is the function of an inlet manifold in a sampling system?

To suck gas sample from the gas stream into the analyzer (B) Signup and view all the answers

What is the purpose of a flow measurement device in a sampling system?

To measure the flow of gas (A) Signup and view all the answers

When selecting a location for an ambient air monitor, what is a priority consideration?

Public access and highest pollutant concentration (A) Signup and view all the answers

Why is it challenging to obtain a representative sample of pollutant concentration in an industrial smokestack?

Because of point-to-point and time-to-time variations (C) Signup and view all the answers

What is the primary objective of source measurement or testing?

To determine emission rates of pollutants from a source (D) Signup and view all the answers

What is the purpose of using gas chromatographs or mass spectrometers in pollutant detection?

To detect and count the amount of pollutant principles (B) Signup and view all the answers

Why is the street level of downtown a better location for an ambient air monitor?

Because it is a more representative location for ambient air (D) Signup and view all the answers

What is a traditional location for an ambient air monitor?

Roof of a county health building or courthouse (C) Signup and view all the answers

What is the purpose of averaging concentration measurements?

To account for variations in instantaneous concentrations (C) Signup and view all the answers

What type of instrument measures instantaneous concentrations of pollutants?

Real-time instrument (C) Signup and view all the answers

What is the problem associated with measuring SO2 gas in air using a light beam?

Interference from CO2 in air (B) Signup and view all the answers

What is the equation to calculate average concentration?

Cavg = ∫cdt (C) Signup and view all the answers

What is the purpose of using a dilute solution of NaOH in measuring SO2 gas?

To react with the pollutant (A) Signup and view all the answers

What is the unit of flow rate mentioned in Example 4.2?

L/min (B) Signup and view all the answers

What is the average PM2.5 concentration in the air drawn through the sampler?

21 µg/m3 (A) Signup and view all the answers

What is the measured change in filter weight?

0.5 mg (A) Signup and view all the answers

What is the purpose of high-quality weighing and sample humidity control?

To ensure accurate measurement of filter weight (B) Signup and view all the answers

What is defined by the EPA standard methods?

The pollutant itself, e.g. SO2 (C) Signup and view all the answers

What is the formula for calculating pollutant molar flow rate?

Pollutant molar flow rate = (gas flow rate) x (pollutant concentration in gas) (C) Signup and view all the answers

What is the purpose of isokinetic sampling?

To maintain isokinetic flow into the sampling probe for particulates (C) Signup and view all the answers