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| Applying Your Knowledge: Measuring Silica |
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| Paul's company
does a good amount of abrasive blasting. His safety and health consultant has
recommended that three of Paul's employees wear sampling devices throughout a day to
collect the particles in the air, and that the samples be sent to a laboratory so that
Paul can know exactly how much silica his workers are breathing. His consultant has told
him about three laboratories which can analyze the samples. The laboratory brochures
provide some basic information: |
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| Lab A |
Lab B |
Lab C |
- Analyzes using IR
- Specializes in the analysis of crystalline silica in coal dust
- Provides pre-weighed filters
- Is accredited for quartz analysis
- Costs the least
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- Analyzes using XRD
- Specializes in industrial hygiene analysis including silica
- Provides pre-weighed filters
- Is accredited for industrial hygiene analysis
- Costs twice as much as Lab A
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- Analyzes using XRD
- Specializes in geological and environmental analysis including silica and silicates
- Does not provide filters
- Is not accredited
- Costs about the same as Lab A
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| Which lab should Paul choose? |
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|
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| Lab A |
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| This may not be
the best choice. Even though Lab A does analyze samples for crystalline silica,
Paul's samples do not involve coal dust. The IR method works well for quartz in coal dust,
but Paul needs a method that will also provide data on other forms of crystalline
silica. This laboratory is accredited which indicates that it does have a good
quality assurance program in place, and it does analyze filters. If Paul chooses this lab
he will want to make sure they can provide results for each of the separate forms of
crystalline silica. Try again |
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| Lab B |
|
Good
choice. Lab B does analyze samples by XRD, does analyze industrial hygiene
(workplace) samples, and does provide the sampling media, all of which are essential to
getting an accurate reading. In addition, the fact that they are accredited indicates that
they have a good quality assurance program in place.
Go on to Comparing with the Legal Limit. |
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| Lab C |
|
This may not be
the best choice. Even though Lab C does analyze samples by XRD and specializes in
silica analysis, it probably does not routinely analyze filter samples. Paul may want to
find out more about its quality assurance program and its knowledge of his type of
samples. Try again.
|
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