Testing for asbestos: What is asbestos point counting?

Within the realm of asbestos sampling there are several analytical techniques.  The most general way to test for asbestos containing material is through Phase Contrast Microscopy (PCM), Transmission Electron Microscopy (TEM) and Polarized Light Microscopy (PLM). 

The first two methods, PCM and TEM are used to analyze air samples. 

The third method: PLM, is used to detect asbestos in a “bulk” sample such as a piece of floor tile, wall texture, hard plaster, pipe insulation, etc.  This discussion will be limited to bulk analysis using the PLM method.  

Why Use Point Counting When Testing for Asbestos?

When a bulk sample of material is found to contain 10% asbestos or less, the sample may be presumed to contain greater than 1% asbestos and treated as such or the sample can be further analyzed via Point Counting.    

What is the difference between PMC & TEM air sampling for asbestos?

Air sampling is used to detect the presence of asbestos fibers in an area. PCM and TEM are two methods used to analyze air samples associated with asbestos fibers.  In addition to determining if the air in a particular area contains asbestos fibers, sampling can also be an indication of how well or how poorly an asbestos removal project is proceeding.  During an asbestos removal project, it is important to keep fiber counts as low as possible to reduce potential exposure to workers, building occupants and to determine if and when the work area is suitable to be reoccupied.

Phase Contrast Microscopy analysis (PCM) is most often used in the asbestos abatement industry.  PCM analysis is not as accurate as Transmission Electron Microscopy (TEM).  The PCM method of analysis can count fibers but cannot positively identify the fibers as asbestos.  Using PCM analysis, fibers of a certain width to length ratio are assumed to be asbestos fibers and counted accordingly.  In comparison, TEM sampling methods use a higher magnification thereby allowing smaller fibers to be detected and allowing the technician to positively identify an asbestos fiber or a non-asbestos fiber (see photo below). 

How can I stop mold from going in my basement?

When it comes to mold contamination, moisture control is the key to prevention. Mold is a fast growing resilient organism which can grow on any organic material. In nature, mold is a valuable part of the ecosystem. Mold aids in breaking down and decomposing leaves and other biological waste products. Unfortunately, mold can get into homes and businesses and can put the occupants in serious danger. Prevention is the best way to handle any mold issue but when mold becomes apparent in the home it needs to be properly handled to avoid health issues and regrowth. The following guidelines for mold prevention and removal will help keep your household safe and clean.

The first step to preventing mold growth is to find where potential moisture sources are.

 When you find a problem with a moisture source, fixing it can be as easy as tightening a leaky pipe or simply adding more ventilation to the room. Specifically, areas like basements may have poor ventilation due to the lack of windows and air movement. In these cases a dehumidifier may be needed. Using a dehumidifier is a great preventative measure, yet the machine itself must be cleaned and emptied regularly to prevent mold spores from spreading back into the air. It is said that 65%-70% humidity is needed for mold to grow. For that reason, it is ideal to keep your house between 30%-50% relative humidity.

Where does asbestos go after it is removed?

Once asbestos has been removed from a residence or business it is important that the materials are properly disposed of. Due to the sensitivity of the substance there is a very strict process that must be followed.

To begin the disposal process, the asbestos must be assigned to one of two categories:

Friable – any substance that contains more than 1% asbestos and can be crumbled by hand when dry.

Non-friable -  if the material cannot be crushed by hand.

If the type of asbestos is unknown it is automatically considered friable material to error on the side of safety.

What Kind of Protection Do Asbestos Workers Use?

When handling a substance like asbestos, regulated precautions must be taken.  In this article, we will discuss what kind of protection asbestos workers wear.

Respirators are probably the most important piece of personal protective equipment used in the removal of asbestos.  In addition, workers must also protect their skin and eyes. For these reasons employees must wear disposable coveralls, gloves, foot covering and head covering as well as protective eye wear. 

How Do I Know If I Have Asbestos?

Unless a material is labeled as containing asbestos, you generally cannot tell if asbestos is present simply by looking at it. In the past, asbestos was added to many types of construction materials to strengthen, insulate, fireproof, and soundproof. For this reason, it is difficult to identify for certain if you have asbestos in your home or building without first having the building tested for asbestos contamination. 

The EPA suggests that you have your home inspected by a trained and accredited asbestos professional if you suspect you may have asbestos containing materials in your building.

The EPA also suggests that you schedule an inspection before you begin remodeling or after your home or building experiences damage where building materials have been disturbed. (drywall crumbling, insulation falling apart, etc.)

Below are some images of asbestos containing material. Keep in mind, the best way to handle any situation where you suspect asbestos may be present is to contact a professional asbestos abatement company or asbestos testing company.

This is just one example of floor tile made with asbestos but there are many different kinds of floor tile that contain asbestos.	Here is a sample of tiny asbestos fibers which can be inhaled and cause the deadly respiratory condition  known as mesothelioma.  This can be found in drywall and other types of construction materials.

These two pictures show a roof covered in asbestos containing material that was used to prevent heat loss.