Methods of Asbestos Testing that you may want to consider

Why do you need asbestos testing? 

Asbestos is harmful to you if it is present in the air as small fibers. When you breathe air with asbestos fibers present, the fibers enter your lungs. Once asbestos fibers become stuck in your lungs or other parts of your body, they can cause various health issues. 

The health issues caused by inhaling or swallowing asbestos fibers can include asbestosis, a chronic lung disease. Asbestos exposure can also lead to mesothelioma, a rare type of cancer that occurs in the lining of the lungs.

Thus, it is vital that you must ensure that the air you breathe is free of asbestos fibers. This is very important in schools, public places, and workplaces. 

What are the agencies that help to detect asbestos?

There are a number of government agencies that can help to detect asbestos in your home, work or other buildings or products. As it deteriorates or is disturbed by construction or demolition, asbestos can become airborne, or contaminate the soil. 

Agencies that can conduct tests to see if there is asbestos present include:

  • Environmental Protection Agency (EPA)
  • Occupational Safety and Health Administration (OSHA)
  • National Institute for Occupational Safety and Health (NIOSH)
  • Asbestos Hazard Emergency Response Act (AHERA)
  • American Society for Testing and Materials (ASTM)
  • Asbestos Information Association (AIA)

“The overall evidence suggests there is no safe level of asbestos exposure.”

Source: National Cancer Institute (NIH) 1

Are there Methods to detect asbestos in air and soil?

There are methods to detect asbestos in the air and materials, such as soil. These methods use optical and electron microscopes for analysis. 

The methods are:

  1. Phase Contrast Microscopy (PCM) 

  2. Transmission Electron Microscopy (TEM)

  3. Scanning Electron Microscopy (SEM)

  4. Polarized Light Microscopy (PLM)

Microscopy is the method of using microscopes to examine and evaluate things that are too small for anyone to see with their eyes. Asbestos fibers can be large and appear as dust, but the fibers can even be microscopic and too small to see. Microscopy helps to detect the presence of asbestos in the air or soil. 

The Four Methods of Testing for Asbestos:

Phase Contrast Microscopy (PCM)Air and Soil
Polarized Light Microscopy (PLM)Soil
Transmission Electron Microscopy (TEM)Air and Soil
Scanning Electron Microscopy (SEM)Air and Soil

What is the PCM Method of Asbestos Testing?
When conducting the PCM method of asbestos testing, an examiner uses an optical microscope to measure asbestos levels in the air. 

You can test materials in their natural state with PCM. Sometimes, you cannot see some objects under a normal light microscope. By using a phase contrast microscope, you can see these objects because of the contrast created between the objects and surroundings. Thus, you can use PCM to find many types of asbestos fibers.

OSHA makes it essential for you to use PCM to measure asbestos levels in air. The most used method is the NIOSH 7400 developed by NIOSH.

You use the PCM guidelines given by OSHA to verify a place, such as a school or a workplace is free of asbestos before you move into the premises. 
In the PCM method, you are not able to separate asbestos fibers from those that are not. This is a drawback of the PCM method. 

The PCM method is low cost. The result is quickly available on-site. This is an advantage of PCM.
What is the TEM Method of Asbestos Testing?
The Transmission Electron Microscope (TEM) method of asbestos testing uses an electron microscope. It can display objects that are extremely tiny, far too small to see with your eye, or even an optical microscope.

An optical microscope can magnify only up to 1,000 times. An electron microscope uses an electromagnetic lens to project images, and can magnify an image up to 1,000,000 times. 

Jointly with AHERA, EPA regulates the use of TEM to test airborne asbestos fibers. It is essential when you want to certify a school or workplace is free of asbestos.
What is the SEM Method of Asbestos Testing?
With the SEM method of asbestos testing, an examiner uses the electron microscope to scan the surface of the test material. You can send an electron beam to interact with the surface. The scan helps to detect asbestos through its interactions. 

SEM has an advantage over TEM and PCM because of the better resolution the scanning electron microscope provides.

You can spot fibers with smaller diameters and shorter lengths with SEM. 

Examiners find it easier to prepare samples with SEM than with other methods.

This method has been developed by the American Society for Testing and Materials (ASTM), but is not required by all agencies.

Unfortunately, SEM is very costly and time consuming. Fortunately it is also generally not required by any laws.
What is the PLM Method of Asbestos Testing?
PLM stands for Polarizing Light Microscope. With the PLM method of asbestos testing, the examiner uses a polarized light microscope to achieve a high degree of sensitivity, detecting the radiation the specimen reflects.

The PLM method is suitable for both qualitative and quantitative analysis, but the PLM generally provides much better results for qualitative than quantitative analysis. 

That means the PLM method of asbestos testing may confirm there is asbestos, but not be able to tell you as certainly just how much asbestos is present.

The National Cancer Institute (NIH) states that “there is no safe level of asbestos exposure.” But higher concentrations of and longer exposure to asbestos can cause more health problems, so it’s important to know how much asbestos you’re being exposed to.

It is essential that you find asbestos in soil. It is more important for EPA’s Superfund Program. You will find asbestos present in many Superfund sites across the United States. The PLM method can help you to find asbestos so that you can remove it and become safe.

While PCM, TEM, and SEM are useful, they are more suitable for testing air samples. The PLM method seems more appropriate for testing soil samples.

Unfortunately, there is no validation of the PLM Method so far.

These are some of the well-established methods available to detect asbestos in the air and soil. You would be safe if you use these methods to find out if the air inside your workplace or school is for occupation. 


If you may have been exposed to asbestos, speak with your healthcare provider about tests and screening to help detect the presence of asbestos fibers and asbestos-related damage.

AsbestosClaims.Law is your comprehensive resource for all things asbestos. We hope this information helps you.

If you believe that your home was contaminated with asbestos, you could be entitled to significant compensation – money you could use to cover the costs of asbestos removal services, pay for medical treatment, and preemptively protect your physical well-being. 

In addition to legal claims, veterans disability, social security and employment protection like workers compensation, FELA and The Jones Act for maritime workers, there are asbestos trusts that have been set up to compensate those harmed by asbestos without having to file a lawsuit.
If you have any additional questions or concerns related to asbestos, including testing for exposure or how to file a claim, please get in touch by email at [email protected], or call or text us at (206) 455-9190.



1 National Cancer Institute (NIH), Asbestos Fact Sheet.
2 National Cancer Institute (NIH), Asbestos Fact Sheet.