Sampling

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Free Webinar: Improving the Quality of Industrial Hygiene Air Sampling Data Through Proper Field Practices

TestAmerica is hosting a free webinar on “Improving the Quality of Industrial Hygiene Air Sampling Data Through Proper Field Practices” on September 20.  The webinar will be presented by Mike McGee, CIH and will provide a basic overview on improving the quality of IH data and avoiding common pitfalls.

Variability in sampling data can result from: the skill level and attention of the person performing the sampling, equipment and sampling media, variability of air sampling flow/sampling rate, recording sampling time accurately, environmental factors, documentation, the representativeness of the samples collected, variation in contaminant concentration during sampling, and transportation of samples from the field to the laboratory.

Topics will include:

  • Sources of field variability
  • Why air volume is only half of the equation
  • What you should know about air sampling pump calibration
  • Field data collection accuracy and adjustments
  • Field data documentation
  • Pitfalls to avoid

Register for the webinar HERE.

Source: TestAmerica

Calculator: Minimum Sample Volume & Required Sampling Time

Want to determine the Minimum Sample Volume needed to ensure you collect enough of a sample volume so that the results are capable of being less than the Exposure Limit? Want to know how long you need to sample at a given flow rate?

If so, use OHShub.com’s Minimum Sample Volume and Required Sampling Time calculator and take the guess-work out of the equation.

Input the:

  • Laboratory Limit of Quantitation (LOQ)
  • Exposure Limit
  • Desired Fraction of the Exposure Limit (essentially a safety factor for sampling)
  • Sampling Rate

And the results will give you the Minimum Sample Volume and Required Sampling Time.

Note:  Ensure that you have the right units and all of the units are consistent.  Units such as parts per million (ppm) for Exposure Limits may need to be converted to mg/m3.

Download the Calculator HERE: (Calculator: MSV & RST (1683))

Common Mistakes: Sampling with Sorbent Tube in Horizontal Position

Hiking: The Path of Least Resistance
Hiking: The Path of Least Resistance

Like hikers, electricity in a circuit, and water flowing downhill, airborne vapors also take the path of least resistance.  Therefore, it is important to maintain proper orientation with a sorbent tube while air sampling.  If the sorbent tube is placed in a horizontal position, “channeling” may occur due to the sorbent falling away from the walls of the glass sorbent tube.  As the vapors take the path of least resistance (i.e. through the “channel”), the effectiveness of the adsorption by the sorbent bed will be decreased because of the effective surface area being diminished.  The sorbent tube should be maintained in a vertical position (or as close as possible) to avoid the “channeling” effect.

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