What To Expect Asbestos Abatement

what-to-expect-asbestos-abatement.

Understand the Rules

If asbestos containing building materials to be removed exceeding 100 square feet and/or contain a bearing wall, a professional asbestos abatement contractor should be hired. Pre-removal of probable asbestos-containing materials will determine the square footage of asbestos containing materials to be removed and provide you with a J-card number. Your contractors will usually need this number for a San Francisco Department of Building Inspection building permit; the Bay Area Air Quality Management District will also need this number for their required 10-Day Notice permit.

The hassle, stop-work orders, fines, lawsuits from neighbors or tenants, etc., etc., etc. is not worth it. The cheap can turn out expensive very quickly.

Asbestos Testing is First

If asbestos containing building materials to be removed exceeding 100 square feet and/or contain a bearing wall, a professional asbestos abatement contractor should be hired. Pre-removal of probable asbestos-containing materials will determine the square footage of asbestos containing materials to be removed and provide you with a J-card number. Your contractors will usually need this number for a San Francisco Department of Building Inspection building permit; the Bay Area Air Quality Management District will also need this number for their required 10-Day Notice permit.

The hassle, stop-work orders, fines, lawsuits from neighbors or tenants, etc., etc., etc. is not worth it. The cheap can turn out expensive very quickly.

Asbestos Abatement Procedures

 

When asbestos containing materials are disturbed or removed asbestos fibers are released into the air.  The first thing your contractors will do is to contain the project area with plastic. This plastic is air-tight. All plastic walls should have a slight bow inward towards the project area.

A professional abatement contractor will put machines in place to safely remove dangerous asbestos fibers from your air. These machines are large, noisy air purifiers or air scrubbers. Because they push more air out than is taken into the project area, this makes sure the asbestos fibers don’t migrate into living or working areas. 

Your asbestos removal contractor will also attach a plastic duct from an air scrubber to a window so the cleaned air can be blown out and the negative pressure maintained inside the work area.

All workers inside the work area will be appropriately dresses with masks that filter asbestos and other dust particles. These masks require a medical doctor to confirm a workers’ lungs are healthy

Do Not Enter the Contained Area

No one except your asbestos removal contractor or his employees should enter the contained area. Trained asbestos testing professionals can also enter this area. 

Even after your asbestos contractor tells you the job it finished, DON’T ENTER THE CONTAINED AREA.

I know those big air scrubbers are noisy and disturb your work or your sleep. The backflow from turning them off may affect your entire building. It is extremely expensive to clean up an “opps” that contaminated an entire home or office building. Because there are hooks on the ends of asbestos fibers, all soft contents (beds, fabric furniture, clothing, rubs) is required to go to a toxic dump site – it cannot be successfully cleaned. Consider how expensive it could become to remove all the contents including the HVA ducting.

You may want to consider a temporary work space or an AirBnB.

Asbestos Clearance

How do you know all the asbestos fibers are out of the air? Air testing. Asbestos fibers are not visible to the naked eye.

There are several types of asbestos clearance testing. 

Asbestos PCM Analysis

Asbestos PCM air sample testing analysis is a method that follows a prescribed standard called the NIOSH 7400 Method.

Asbestos PCM samples use a light microscope to detect fibers visually. The microscope can be hand carried; one of the advantages of this method is mobility. Samples can even be analyzed on-site, which decreases the turnaround time required for obtaining results. The microscope magnifies objects approximately 400 times their actual size.

The main disadvantage of the Phase Contrast Microscopy methodology is that it is not asbestos specific. The analyst counts any fiber that falls into a field of view that is greater than or equal to 5 μm in length, with a 3:1 aspect ratio (three times longer than its width).

Asbestos TEM air samples with a result of <70 s/mm² (structures/millimeter squared) have achieved final clearance. Lab results show asbestos fibers to be non-detect.

 

Asbestos TEM air samples with a result of >70 s/mm² (structures/millimeter squared) indicate asbestos abatement is necessary. 

Asbestos TEM Analysis

Asbestos TEM (Transmission Electron Microscope) air sample testing uses electrons to create images, fine crystal patterns and analyzes the chemical makeup of fibers or structures encountered in the air sample.

The machinery required is not very mobile and is very sophisticated.

It magnifies objects at least 20 times their actual size. This method also is asbestos-specific; so specific that it can indicate the type of asbestos fibers in the air sample. This method is often used when there are interfering fibers which cause the PCM results to be very high, but asbestos fibers are not suspected as the cause of their high-fiber count.

This method is most appropriate for final clearance samples either due to regulation (AHERA) or liability issues. By law, schools, etc., must use this method. This is also most appropriate for litigation and real estate transactions.

Asbestos PCM air samples with results <0.01 f/cc (fibers per cubic centimeter) are acceptable for worker safety in accordance to OSHA’s PEL for worker safety.

Asbestos PCM air samples with results >0.01 f/cc (fibers per cubic centimeter) are not acceptable for worker safety in accordance to OSHA’s PEL for worker safety. These samples are shown as FAIL.

Asbestos Tape Lifts

Scotch-type clear tape is gently pressed on hard surface contents that have been cleaned of asbestos fibers. This is a presence or absence only test.

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