Strategies for leaving asbestos-containing floor tiles or sheet flooring safely in place in a building:

Choosing an appropriate material to cover-up or coat the surface of a sound, well-adhered floor can protect against future damage or asbestos particle release in the building.

This article series assists building buyers, owners or occupants in reducing the risk of asbestos exposure from flooring that contains or is suspected to contain asbestos.

We provide photographs and descriptive text of asbestos insulation and other asbestos-containing products to permit identification of definite, probable, or possible asbestos materials in buildings.

Page top photo: vinyl asbestos floor tiles in the kitchen of a 1970's home - before covering over with epoxy floor paint.

How to Safely Leave Asbestos-Containing Floor Tiles in Place

Advice About Covering or Sealing Asbestos Floor Tiles

Asbestos is safe and legal to remain in homes or public buildings as long as the asbestos materials are in good condition and the asbestos can not be released into the air. - US EPA

The most economical renovation procedure for asbestos-floor tiles would be to leave the tiles in place, picking up any very loose scraps for enclosure in plastic bags for disposal (your municipality may permit disposal as construction debris, or you may have to hand it over to an approved waste hauler - double-bagged it should not be an issue), followed by installing a new layer of flooring over the existing material.

Photo at left: ceramic tile installed directly over asphalt-asbestos floor tile in a 1970's home. [Click to enlarge any image]

• The age of your floor means it is asbestos suspect
• Asbestos was very commonly used in vinyl and asphalt based floor tiles in the 1960's.
• Asbestos is an airborne particle hazard, not like something that "emits" a hazard such as radioactive materials. So if the material is sound, intact, undisturbed, the risk of particle release is very low.
• You can reduce the hazard from asbestos-containing floor tiles by several measures we list here and by other suggestions in government documents and references we cite in our online articles on this topic.
  • Leave in place & seal: In residential applications if the flooring is in good condition you can gently clean, restore, and coat the flooring with an epoxy paint or with a clear restorative coating. Below we illustrate this procedure using epoxy floor paint.
  • You can simply cover the suspect flooring with a new material: -- wall to wall carpeting -- vinyl or sheet resilient flooring -- new layer of resilient tile flooring -- a wooden subfloor and new resilient tile flooring. At above left we illustrate this result: ceramic tiles have been installed atop the original floor covering.
  • If your new floor is to be tile placed on top of old asbestos tile flooring, you might need to use a floor filler over openings left where broken tiles were removed, so that the floor surface below the new flooring is adequately smooth.
  • If the floor structure is sufficiently rigid so as to avoid flexing and cracking, ceramic tile can also be installed over an appropriate subfloor layer
  • If the floor surface is in good condition (no loose, broken tiles) and is in a residential area (not a school or public space) and not subject to heavy wear or use of mechanical grinders, buffers, etc., you might consider cleaning the floor surface (washing), painting it with an epoxy floor paint,
    
    and if/when the epoxy painted surface is scuffed, restore that surface with a floor cleaning and rejuvenation product that adds additional clear coat layers.
  • Use a HEPA vacuum cleaner when cleaning up house dust as that type of filter will capture most ultra small particles including asbestos dust if such is even present
  • Do not use floor sanders, power or machine driven floor polishers on asbestos-suspect flooring
• Do not permit demolition of the floor without taking appropriate asbestos-dust control measures

Reader Question: What are the options for covering asbestos-suspect floor tiles or sheet flooring?

We are renovating a small bathroom that has resilient flooring of uncertain age, but from the style we think the floor tiles are from the 70s.

We want to cover this floor tile to avoid an asbestos hazard. What are some options. - Anon.

Reply: asbestos-containing flooring in good condition is not "radioactive" and does not spontaneously emit harmful particles

Remember that the hazard from asbestos-containing floor tiles is not like something that's "radioactive" - if the flooring is not damaged, if you avoid making a dusty mess by demolition, and more, if it the flooring can be covered and protected from damage, it is not harmful if left in place.

Current best asbestos advice is to avoid the dust and mess of demolition of vinyl asbestos flooring if you can simply cover it with another material.

Question: how can we identify these 1950's 9x9" basement floor tiles to find out if they're "asbestos" ?

We are planning to gut and remodel a basement in a house we have been living in for a few years now. The basement previously was used just for storage, but we want usable space there. About 400 Sq ft of the 700 we will be remodeling has existing tile while the rest is just painted cement floor.

Some of the tile is missing, one section cracked, but covered with foam play mats, which my wife installed initially when the house was purchased.

These are 9x9 tiles, and we have no idea about history or age.

The house is a 1950s home, but it is not clear when the basement tile was installed. A search online lead me to your site, and they do look like Armstrong tiles possibly, but I wanted to get an opinion from somebody with more expertise.

Me plan was to have the floor removed and to go with an epoxy floor covering, as it is a basement floor, where water is always a possibility and carpet is not something we want to risk.

If it is not advised, and it would be better suited to go with a different floor covering, we would still need to deal with the areas missing tile, but we have a contractor that can aide in this.

I will attach some photos that hopefully can help identify the tiles in question. - Anonymous by private email 2018/06/02

Reply: asbestos-containing flooring does not mean we have to undertake an expensive and dangerous asbestos removal project

You will find an exact match to your flooring in the ID-library of asbestos flooring beginning

at ASBESTOS FLOOR TILE IDENTIFICATION PHOTOS 1949-1959- (floor tiles) where you'll see your flooring in the early Armstrong (or similar manufacturers) vinyl asbestos or asphalt asbestos 9x9" (and other sizes) flooring.

Do you need to test the floor for asbestos?

From the age and appearance of the floor, I would not bother testing it for asbestos, spending instead on proper cleanup and sealing of the surface.

Even without testing, given the appearance and known age of your floor, it would be prudent to treat such flooring as "PACM" or "Presumed Asbestos Containing Material".

The presence of known asbestos-containing flooring does not mean we should panic nor that we should undertake an expensive and dangerous asbestos removal project.

Do you have to remove the existing floor tiles?

Asbestos is safe and legal to remain in homes or public buildings as long as the asbestos materials are in good condition and the asbestos can not be released into the air.

Generally the safest approach is to leave such flooring alone and to cover it with a coating or with another layer of flooring.

Keep in mind that even if you removed the floor tiles the remains of the mastic adhesive below would make use of an expoxy floor paint problematic - it may not properly adhere. You'd need to also remove the adhesive (which may also contain asbestos), and then clean the surface to make it bond with the floor paint.

All of that demolition and cleaning, performed properly and safely, would be quite costly. If the rest of your floor is sound and well-adhered, that expense is probably not necessary.

Options for leaving the flooring in place

For the situation you describe,

see ASBESTOS FLOORING LEFT IN PLACE where I describe using an expoxy coating on a floor in generally good condition and provided that the remaining floor tiles are well-adhered to the floor below.

You can buy floor tiles that can fill-in the voids in the existing floor. Select a floor tile of the same thickness and surface texture (not embossed). Armstrong as well as other floor tile manufacturers sell floor tiles in various thicknesses, one of which should match the thickness of the existing tiles.

Other advice on various options for an asbestos-floor tile is

at ASBESTOS FLOORING HAZARD REDUCTION

For a floor whose tiles are well adhered except for small areas of damage such as you show, I would prefer to damp-wipe clean up a few broken tiles, replace missing ones with new tiles of the same thickness, then expoxy-seal or otherwise cover-over (sheet vinyl) the existing floor.

If you must remove the 9x9 asbestos-suspect flooring

Watch out: If when you remove the rest of the current covering over the floor you find a significant number of loose, poorly-adhered, or broken floor tiles, OR if for other reasons you are compelled to remove the floor (not the recommended option)

see ASBESTOS FLOORING REMOVAL GUIDE .

Watch out: Do not run a conventional vacuum cleaner over such areas as you'll just cause more particles to become airborne.

On any of our asbestos-related InspectApedia pages, at CONTINUE READING you will find

a complete ARTICLE INDEX to ASBESTOS HAZARDS

For advice on handling irregularities in floor surface after loose floor tiles have been removed see

RESILIENT FLOORING VINYL or CORK

We would have much appreciated hearing any comments, criticize, suggestions, or further questions that you may have taken after you've taken a look at the articles I've cited.

InspectAPedia is an independent publisher of building, environmental, and forensic inspection, diagnosis, and repair information provided free to the public - we have no business or financial connection with any manufacturer or service provider discussed at our website. We do not sell products nor services.

Examples of asbestos floor tile or sheet flooring cover-ups that can work

• Carpeting (we don't recommend wall to wall carpets in basements nor in bathrooms)
• A new layer of resilient flooring, sheet or tiles, installed directly over the existing floor covering (typically using mastic) provided the current floor surface is smooth and sound
• A new layer of resilient flooring, sheet or tiles, installed over hardboard or other solid underlayment that is placed over the existing floor covering and secured by nails or screws to framing below in order to provide a smooth leveling surface.
• A new layer of resilient flooring, sheet or tiles, installed over a pour-on leveling compound (a concrete mix) used to level uneven floors (most suitable for concrete slab floors, may not be recommended over a wood framed-floor that is not framed solidly enough to resist flexing as the concrete pour-on underlayment may crack)
• A layer of epoxy floor paint and one or more layers of clear coat sealant.
  
  This step is described at ASBESTOS FLOORING LEFT IN PLACE-EPOXY PAINT
• Coating good condition asbestos floor tiles with a rejuvenating sealant or gloss topcoat. This approach using an epoxy floor paint is discussed and illustrated just below.
  
  Also see ASBESTOS ENCAPSULANTS & SEALERS - coatings, encapsulants, fiber release control for asbestos containing materials

Watch out:  We do not recommend installing ceramic tile over a wood-framed floor before you have checked the flexibility of the floor system, in particular if the floor framing covers a larger span, say a dining room, or an area of heavy usage, say an entry hallway. The worry is that flexing floor framing may cause cracks in the ceramic tile job. Usually the floor can be stiffened sufficiently to avoid cracking either by reinforcing framing from below or by adding a layer of stiff underlayment.

Watch out:  when adding a new layer of floor covering that requires underlayment or leveling compound, the increase in floor height where it abuts adjacent flooring of other rooms can create a trip hazard.

Advice for Coating or Painting Over Asphalt Asbestos Flooring

or Vinyl Asbestos Floor Tiles Using Epoxy Paint and/or a Rejuvenation Sealer or Gloss Coat

Our photographs demonstrate the use of an epoxy floor paint to provide a durable and safe coating for a vinyl-asbestos tile kitchen floor that was otherwise in good condition.

The original asbestos floor (shown above), installed when the home was built in the 1970's, was cleaned to provide a good bond for the epoxy floor paint.

No sanding, grinding, or other dust-producing methods were used.

For periodic maintenance, the black epoxy floor is cleaned and re-sealed (above right) using the floor rejuvenation products shown below.

The original expoxy paint coating was made in 2000; the photo above shows the condition of the floor around 2015, more than a decade later.

Reader Question: how can I seal vinyl asbestos floor tiles so that I can leave the flooring in place?

I am looking for information on Armstrong die cut inserts from around 1952.

Also are there any recommended ways to seal these floors so you can enjoy the look but without any asbestos concerns? Thanks, Sarah

[This Q&A originally appeared

at ASBESTOS FLOOR TILE IDENTIFICATION PHOTOS 1949-1959, June 2011.

Reply: residential vinyl-asbestos floor tiles in good condition can be gently cleaned and clear-coated or sealed - vinyl tile floor restoration

As we noted in quoting the US EPA and other sources,

Asbestos is safe and legal to remain in homes or public buildings as long as the asbestos materials are in good condition and the asbestos can not be released into the air.

About sealing vinyl-asbestos tile floors, especially in residential use where school or public regulations and public access worries don't apply, I've had great success using epoxy paints but you may find a shorter-term less durable but safe coating using clear-coating floor restorer products.

You will need to repeat the coating from time to time.

We did this recently in a New York home following this procedure:

• The floor was washed with mild detergent and water.
  
  Watch out: take care when selecting cleaners or floor stripping chemicals or treatments. Some of these can stain, damage, or even dissolve the flooring.
  
  See STRIPPING a FLOOR BEFORE SEALING.
• Then we used a spray cleaner recommended by the floor restorer manufacturer. The spray cleaner removes old wax residues. See our photo of Rejuvenate™ floor cleaner (above left).
• Next we used a magic marker to color in some gouges that had marred the floor surface.
• Finally we coated the flooring with the floor restorer product. The floor looked new, and great. See our photo of Rejuvenate™ floor clearcoat sealant (at left).
  
  In sum, provided that your floor tile is not damaged and remains soundly glued in place, in residential use it may be fine to seal its surface and leave it alone.

if you maintain a hard clear coating on top of the floor surface you won't be releasing any measurable level of asbestos fibers by normal foot traffic.

Watch out: We advise against using any power equipment such as sanders, grinders, saws, or even steel-wool buffers on vinyl-asbestos flooring out of concern for the effect of grinding of the surface and concomitant release of asbestos particles into the building air.

Also see ARMSTRONG DIE-CUT FLOOR TILES

Reader Question: Armstrong asbestos floor tile diecut inserts from around 1952 - ways to seal these floors?

Am looking for information on Armstrong diecut inserts from around 1952.

Also are there any recommended ways to seal these floors so you can enjoy the look but without any asbestos concerns? Thanks, Sarah - Sarah 6/23/11

Reply: gentle cleaning followed by floor restorer clear coating protects from asbestos fiber release

Sarah:

Our photos show examples of some of the diecut flooring inserts from the 1950's; I'm not sure what other information you seek.

About sealing vinyl-asbestos tile floors, especially in residential use where school or public regulations and public access worries don't apply, I've had great success using clear-coating floor restorer products.

We just did this recently in a New York home. The floor was washed with mild detergent and water. Then we used a spray cleaner recommended by the floor restorer manufacturer.

The spray cleaner removes old wax residues. Next we used a magic marker to color in some gouges that had marred the floor surface. Finally we coated the flooring with the floor restorer product. The floor looked new, and great.

In sum, if you maintain a hard clear coating on top of the floor surface you won't be releasing any measurable level of asbestos fibers by normal foot traffic.

Also see ASBESTOS FLOORING HAZARD REDUCTION for more ways to reduce the asbestos hazard in asbestos-suspect or presumed asbestos-containing flooring.

Stripping Asbestos-Containing Asphalt Floor Tile or Sheet Flooring

Before sealing or painting-over an asbestos-containing floor that is to be left in place you will need to clean the floor surface of loose dirt and to remove wax coatings so that the sealant or epoxy floor paint will bond to the floor surface.

As we discussed earlier in ASBESTOS FLOORING LEFT IN PLACE, we used a spray cleaner recommended by a floor restorer manufacturer.

The spray cleaner removes old wax residues. See our photo of Rejuvenate™ floor cleaner there.

Watch out: do not use any floor cleaning method that involves abrasion, such as stainless steel buffing pads, sanding, grinding, chopping, scraping, NOR solvents that can damage the floor as these may increase the hazard of asbestos exposure to workers and occupants as well as damaging the floor.

Watch out: take care when selecting cleaners or floor stripping chemicals or treatments. Some of these can stain, damage, or even dissolve the flooring.

The following advice on stripping a floor, provided by US Chemical (cited below) was written in general terms and was not intended to apply only to asbestos-containing asphalt-based flooring, but it's still pertinent.

There are 2 types of strippers, alkaline strippers and solvent strippers. Both strippers are diluted with hot water.

Alkaline strippers contain caustics, silicates or monoethanolamine that breaks the polymer bonds of the floor finish.

Strippers containing silicates should not be used on marble, because the silicates can turn the granite gray.

Alkaline strippers can also damage asphalt tiles but are a better choice than solvent strippers on asphalt tiles. Alkaline strippers are generally faster than solvent strippers but need more thorough rinsing.

Solvent strippers contain glycol ethers or alcohols to break down the finishes.

Alcohol based strippers should only be mixed with cold water and should not be used on asphalt, rubber, terrazzo or linoleum floors.

Solvent strippers are the best for stone floors and alkaline strippers are the best for resilient floors.

New tiles have a finish applied during manufacturing, called a mill finish, that needs to be stripped off before the tiles can be sealed or finished.

Solvent based strippers should not be used on tile floors that are less than 2 years old as they can lift the tiles by dissolving the adhesive.

Asphalt tiles (usually 9” squares) should not have solvent based strippers used on them, because the solvent leaches the color of the tile.

Solvent strippers will remove the paraffin from rubber floors, making them brittle.

When used on terrazzo they can leave glycol ether residues, which can be reactivated by a water-based finish. This can strip the floor from the bottom up.

Stripping solution should be applied with a mop and bucket, not an auto scrubber.

If an auto scrubber is used, stripping solution can be left in the scubber, which can damage the scrubber, and then the scrubber can’t be used for the rinse water.

Before measuring the stripper, make sure that the mop bucket is marked with gallon increments. This allows for easy measuring of the stripping solution.

A diluted gallon of stripper solution will strip approximately 600 sq. ft. of floor with an average number of coats of sealer and finish on it. - US Chemical (2016)

• FLOOR FINISHES & FLOOR CARE [PDF] US Chemical, 316 Hart St., Watertown, WI 53094 USA Tel:L (800) 424-1075 Website: http://www.uschemical.com, retrieved 2018/12/03, original source: http://www.uschemical.com/wp-content/uploads/2016/04/L000238_FLOOR_FINISHES_FLOOR_CARE_BR.pdf

Paints & Floor Sealants for Floor Tile Mastics / Cutback Adhesives

Where some or all old floor tiles have been removed the floor tile adhesive, also called cut-back adhesive or tile mastic will remain. Removing old floor tile cutback adhesive is a horrible job that you should avoid in favor of covering the floor with resilient tile or sheet flooring, carpeting, engineered wood, laminate flooring or a similar product.

However there are at least two situations in which we need to paint-over and seal exposed floor tile adhesive even for a floor we intend to cover.

1. We intend to paint-over spots where floor tiles were removed (with epoxy floor paint) and keep the original tiles in place without adding new layers of flooring, but there are a few areas where tiles lifted or were removed, exposing the floor tile mastic.
   
   Before gluing down replacement tiles in preparation for expoxy-painting we might want to prepare the old mastic-coated surface to be sure that the replacement floor tiles will remain glued in place.
   
   Using epoxy paint to seal and keep an old asbestos-containing tile floor is described beginning
   
   at ASBESTOS FLOORING LEFT IN PLACE
2. We need to level spots where floor tiles were removed so that variations in the original floor surface don't telegraph up through a new layer of resilient sheet flooring to be installed.
   
   Here too we want to prepare the old mastic-coated surface to be sure that the floor leveling compound we apply, or fill-in floor tiles that we stick down will remain in place beneath the new resilient floor.
   
   Using leveling compounds or glue-down filler tiles to level out an old tiled floor prior to covering it with resilient sheet flooring or epoxy paint is described
   
   at FLOOR TILE BASE LEVELING

There are at least three floor tile mastics / cutback adhesives you may encounter:

Black Asphalt-Based Floor Tile Mastic

Black asphalt-based floor tile adhesive, often containing asbestos. This material is not friable unless some fool runs a power sander or scraper over it. Although it can be partly removed using organic solvents, that approach is dangerous and unnecessary unless you are trying to restore a historic and valuable wood floor below.

Instead it's better to leave this adhesive in place and to cover-over the floor with new flooring materials.

If the floor is to be covered with a new layer of flooring such as sheet vinyl or vinyl tiles or even carpet padding and carpeting, there is essentially no risk that asbestos particles can move up from the old floor into the occupied space; nothing is abrading the old asbestos-containing floor tiles and they're covered by a membrane of one or more layers of new material

If however you do not want to add more layers of flooring material another option is to clean and seal the original asbestos-containing floor tiles using an epoxy paint designed for use on floors. I've found that that treatment is very durable - having tested our original installation in a building for nearly twenty years.

Tan or Brown Solvent-Based Floor Cut-Back Adhesive

Solvent-based tan floor tile mastic: Some tan or brown colored floor tile or resilient flooring adhesives were organic-solvent based and can be dissolved and scraped up but the process is difficult, involves working with potentially dangerous solvents, and is probably a bad idea.

Tan or Brown Water-Based Flooring Adhesive

Water-based tan or brown floor tile adhesive: Some tan or brown-colored floor tile or sheet flooring adhesives were water based and can be dissolved and scraped up using simple water.

I [DF] removed water soluble tan floor tile mastic in a small area at an entry door in Wappingers Falls, NY after first trying odorless paint thinner, lacquer thinner and other terrible stuff. To my shock water took the adhesive right up. But this was an exception to the general experience.

For another approach to sealing a damaged asphalt- or vinyl-asbestos tiled floor that's uneven and damaged,

see POURED-IN-PLACE FLOORING, RESILIENT - pour on a whole new floor surface

Mastic-Coated Floor Paint & Sealant Products

Illustration: PerfectPrimer® being painted over an old floor surface with cut-back adhesive, adapted from the company's literature, cited below.

Watch out: some primer/sealer paints and possibly some floor leveling compounds will react with or partially-dissolve or bleed-through or bond poorly with tile mastic adhesives, particularly asphalt-based adhesive. Be sure that the products you use are described by their manufacturer as suitable for painting over floor cutback adhesive. Here are some examples.

• ASBESTOS ENCAPSULANTS & SEALERS - this is our complete list
• Mapei PRIMER T [PDF] MAPEI Americas Headquarters 1144 E. Newport Center Drive Deerfield Beach, Florida 33442 USA, Technical Service: 1-800-992-6273 (U.S. and Puerto Rico) or 1-800-361-9309 (Canada). For help with locating a distributor of MAPEI products, call Customer Service at 1-800-426-2734 (1-800-42-MAPEI).
  
  Website Excerpts: Use Primer T when applying a self-leveling underlayment on properly prepared suitable substrates.
  
  Primer T is a low-VOC, magenta-colored, water-based acrylic primer that enhances the performance and adhesion of self-leveling underlayments (SLUs) on nonporous and porous substrates. Suitable for a wide variety of substrates, Primer T combines excellent versatility with easy, low-odor application.
• PerfectPrimer, Specialty Solutions Manufacturing, Inc., 119 South 3d St New Hyde Park, NY 11040 USA Tel: 718 736 8477 Web: PerfectPrimer.com Email: info@perfectprimer.com
  
  This sealant is marketed as safe for use over asbestos tiles, concrete, and mastics and is described by the company as an asbestos encapsulant.
  
  Website excerpt: PerfectPrimer® is a complete floor prep system and universal primer/sealer. It forms a powerful molecular bond between nearly every coating or modified cement, with any clean, sound substrate including: wood, cut-back glue, sealed concrete, metal, roofing materials, ceramic tile, VCT, epoxies, masonry, and linoleum.
  
  The company provides these and other helpful guides:
  
  PerfectPrimer® for ASBESTOS ENCAPSULATION & OVER MASTICS [PDF] retrieved 2019/11/10 original source: op. cit.
  
  PerfectPrimer® APPLICATION GUIDE [PDF] retrieved 2019/11/10 original source: op. cit.
  
  Watch out: according to the company's primer selection chart, PerfectPrimer will bond to most coatings and virtually any surface, but it is not designed for use on un-coated concrete nor below-grade nor on rusty surfaces. Contact the company directly for product selection advice.
  
  
• POURED-IN-PLACE FLOORING, RESILIENT - pour on a whole new floor surface
• SerpiFlex Asbestos Encapsulant

Managing Asbestos Left in Place in buildings

Watch out: if your asbestos-containing floor looks like the one in this photograph, sealing such a floor is not a reasonable approach.

Removal of the flooring is required, and possibly the mastic adhesive needs to be removed as well.

Quoting below from the following U.S. EPA references includes some advice on managing asbestos in place in buildings:

• ASBESTOS ENCAPSULANTS & SEALERS - coatings, encapsulants, fiber release control for asbestos containing materials
• EPA Guidance for Controlling Asbestos-Containing Materials in buildings, NIAST, National Institute on Abatement Sciences & Technology, [republishing EPA public documents] 1985 ed., Exposure Evaluation Division, Office of Toxic Substances, Office of Pesticides and Toxic Substances, U.S. Environmental Protection Agency, Washington,D.C. 20460
• MANAGING ASBESTOS in PLACE: A Building Owner's Guide to Operations and Maintenance Programs for Asbestos-Containing Materials ("Green Book"), web search 08/11/2010, original source: http://www.epa.gov/asbestos/pubs/management_in_place.html
  
  How to Develop and Maintain a Building Asbestos Operations and Maintenance (O&M) Program, This information is designed to assist building owners and managers in understanding how to develop and maintain an operations and maintenance program for asbestos-containing materials in their buildings.
• Monitoring Asbestos-Containing Material (ACM), U.S. EPA, web search 08/11/2010, original source: http://www.epa.gov/asbestos/pubs/section6.html - no longer on-line, quoting:
  

  A visual re inspection of all ACM should be conducted at regular intervals as part of the O&M program to help ensure that any ACM damage or deterioration will be detected and corrective action taken.

• EPA's ASBESTOS REGULATIONS FOR SCHOOLS (the Asbestos Hazard Emergency Response Act, "AHERA") [PDF] (96 pp, 589k), web search 08/17/2010, original source: http://www.epa.gov/asbestos/pubs/2003pt763.pdf, require that an accredited inspector re inspect school buildings at least once every three years to reassess the condition of ACM.
  
  The AHERA regulations for schools also require a routine surveillance check of ACM every six months to monitor the ACM's condition. This surveillance can be conducted by a trained school custodian or maintenance worker.
  
  While only school buildings are required to have surveillance checks every six months, it is a good practice for other buildings with ACM. The asbestos program manager (APM) should establish appropriate surveillance and re inspection intervals, based on consultation with the building owner and any other qualified professionals involved in the O&M program.
  
  EPA recommends a visual and physical evaluation of ACM during the re inspections to note the ACM's current condition and physical characteristics. Through this reinspection, it is possible to determine both the relative degree of damage and assess the likelihood of future fiber release.
  
  Maintenance of a set of visual records (photos or video) of the ACM over time can be of great value during reinspections.

EPA recommends a visual and physical evaluation of ACM during the reinspections to note the ACM's current condition and physical characteristics.

Additional Asbestos Exposure Prevention Measures for Asbestos Hazards

• Supplemental Air Monitoring for Asbestos Hazards
  
  As part of an O&M program, a carefully designed air monitoring program to detect airborne asbestos fibers in the building may provide useful supplemental information when conducted along with a comprehensive visual and physical ACM inspection and reinspection program.
  
  For employees who are, or may reasonably be expected to be exposed to airborne concentrations of asbestos fibers above the permissible limits set by the Occupational Safety and Health Administration (OSHA), regulations require that the employer conduct both initial and periodic air sampling.
  
  For more information about the OSHA exposure monitoring requirements, see the OSHA regulations at 29 CFR § 1910.1001(d) found at http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=9995

  If the ACM is currently in good condition, increases in airborne asbestos fiber levels at some later time may provide an early warning of deterioration or disturbance of the material. In that way, supplemental air monitoring can be a useful management tool.
  
  If an owner chooses to use air monitoring in an "early warning" context, a knowledgeable and experienced individual should be consulted to design a proper sampling strategy. (See Useful Links for more information on air monitoring, found at http://www.epa.gov/asbestos/pubs/section10.html .)

  This air monitoring should supplement, not replace, physical and visual inspection. Visual inspection can recognize situations and anticipate future exposure (e.g., worsening water damage), whereas air monitoring can only detect a problem after it has occurred, and fibers have been released.

• Sampling Methods  for Asbestos Hazards

  Note that the collection of air samples for supplementary evaluation should not use aggressive air sampling methods. Aggressive sampling methods, in which air is deliberately disturbed or agitated by use of a leaf blower or fans, should only be used at the completion of an asbestos removal project inside the abatement containment area.

• Methods of Air Sampling Analysis for Asbestos Hazards - comparison of TEM & PCM Asbestos Testing

  The most accurate and preferred method of analysis of air samples collected under an O&M program requires the use of transmission electron microscopy (TEM).
  
  Phase contrast microscopy (PCM), which is commonly used for personal air sample analysis and as a screening tool for area air monitoring, cannot distinguish between asbestos fibers and other kinds of fibers which may be present in the air. PCM analysis also cannot detect thin asbestos fibers, and does not count short fibers.
  
  TEM analysis is more expensive than PCM analysis.
  
  However, the more accurate information on actual levels of airborne asbestos fibers that can be derived from TEM should be more beneficial to the building owner who elects to use supplemental air monitoring in the asbestos management program.
  
  TEM analysis is most reliably performed by laboratories accredited by the National Institute of Standards and Technology - http://ts.nist.gov/Standards/scopes/temtm.htm- and who follow EPA’s quality assurance guidelines.
  
  (SeeReferences or Citations , U.S. EPA, Dec. 1989, Transmission Electron Microscopy Asbestos Laboratories: Quality Assurance Guidelines. Washington, DC: EPA 560/5-90-002) found at http://ts.nist.gov/Standards/scopes/temtm.htm

• Selecting a Lab to Test Samples for Asbestos
  
  Selection of a reliable and experienced air monitoring firm and analytical laboratory is important, if the building owner elects to conduct supplemental air monitoring under the O&M program.
  
  A consultant knowledgeable in air sampling and analysis protocols can be contacted for recommendations if the building owner or APM has limited knowledge in this area.
  
  Contact your state asbestos regulatory agency (5 pp, 17k) (original source http://www.epa.gov/asbestos/pubs/statecontactsapril2009.pdf ) for information on how to find an accredited asbestos professional.
  
  In addition, the National Institute for Standards and Technology (NIST) maintains a listing of accredited asbestos laboratories under the National Voluntary Laboratory Accreditation Program (NVLAP). You may call NIST at (301) 975-40

 

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Reader Q&A - also see RECOMMENDED ARTICLES & FAQs

On 2022-09-21 by InspectApedia (mod)

@Anonymous,

Please take a look at the information we discuss at

ASBESTOS MATERIAL SEALINGS & COATINGS
https://inspectapedia.com/hazmat/Asbestos-Sealers-Encapsulants.php

On 2022-09-21 by Anonymous

Hello all, wondering what type of encapsulation primer/paint you think is best! I've seen quite a few online for sale, but having a hard time tracking any down. I see perfect prime but its not available in time for my needs.

On amazon I have found serpiex (sp) and a-b-c but they both seem to be made by the same company and I'm not sure if they are for flooring, or just insulation/soundproofing materials as stated in their literature. Has anyone used a fiberlock brand? All this widom on here has been super helpful.

On 2022-09-21 by InspectApedia-911 (mod)

@Keegan,

Use the underlayment that the manufacturer of your flooring recommends. That might simply be red rosin paper or felt paper or something else.

See also

ASBESTOS ENCAPSULANTS & SEALERS

inspectapedia.com/hazmat/Asbestos-Sealers-Encapsulants.php

On 2022-09-20 by Keegan

@InspectApedia-911, ok so sounds like I have some options. I am doing lvt over it so can you reccomend a suitable underlayment material that I could use in leiu of encapsulation primer? I know it has an attached backing but not sure if thats sufficent.

On 2022-09-20 by InspectApedia-911 (mod)

@Keegan,

If you are gluing down a new layer of flooring of some type then you need to use one of the encapsulates or sealers after thoroughly cleaning the floor surface.

If you were for example installing engineered wood or laminate flooring on top of that old floor then any underlayment would be sufficient.

See also

ASBESTOS ENCAPSULANTS & SEALERS

https://inspectapedia.com/hazmat/Asbestos-Sealers-Encapsulants.php

On 2022-09-20 by Keegan

@InspectApedia (Editor), I get that 100%. I work with the public in youth sports and tend to always skew towards the safe answer for liabilty as well.

When researching encapsulating paint like ABC or serpiflex, I am not finding anything that says specifically it is suitable for tile application other than perfect prime. Will all of them be effective still? Would installing a vapor barrier be equally as effective as priming? What about epoxy? Thanks for your time and consideration!

On 2022-09-20 by InspectApedia (Editor)

@Keegan,

Absolute key is that the tiles are well adhered.

Beware when asking advice, of the OPM problem - see Other People's Money: the OPM Problem https://inspectapedia.com/home_inspection/Other_Peoples_Money.php

On 2022-09-20 by Keegan

@InspectApedia-911, yes that is absolutely correct. They are still well adhered to the floor outside of a tiny area they they are curled up (maybe half inch) so that's great to hear.

A few guys at the box store told me they all had to be pulled and the encapsulant wouldnt work. Are you familiar with abc fiberlock? good product? Thanks again you've been a tremendous help.

On 2022-09-20 by InspectApedia-911 (mod)

@Keegan,

You said

there is a bit of cracking on top of the tile from sun damage and one has a small section missing.

I understand that to mean that the tiles are still well adhered to the floor. If that's correct then using a sealant followed by installing a new layer of flooring a top the old would be perfectly appropriate.

On 2022-09-20 by Keegan

@InspectApedia-911, here is the last area of damage in the entire room.

Thanks again for this site/thread, its been really helpful.

On 2022-09-20 by Keegan

@InspectApedia-911, I guess what I've been led to believe is is there cannot be any damage to the tiles at all for the encapsulation primer to work.

Looking at the tiles in the original picture and this one as well, there is a bit of cracking on top of the tile from sun damage and one has a small section missing (this picture). I just wanted to make sure encapsulation was suitable with this cracking on top.

I will wet and vacuum with a hepa shop vac prior to encapsulation.

Would you think a vapor barrier would be better with the cracking or should i use voth under the lvt? Thanks a ton.

On 2022-09-19 by InspectApedia-911 (mod)

@Keegan,

Sure, why not? Perhaps I'm missing something about the question.

On 2022-09-19 by Keegan

I am redoing a small 13×18 office in my house. The majority of tile is in good condition and I plan to encapsulate with ABC or perfect prime and then cover with lvt. There are about 6-8 tiles by the windows that are in this condition. Can I still use and encapsulating agent over them after they are cleaned?

On 2022-07-23 by InspectApedia-911 (mod)

@Jonny,

If you can't get one of the primers recommended for use over asbestos floor remains I would use any primer that you can to coat the surface.

The disturbance or asbestos release from a screw hole or nail hole later will be trivial and comparison.

Then you can cover that with a temporary layer of resilient sheet flooring until you're ready to do something more aggressive.

The new vinyl sheet flooring forms a continuous membrane. There's no meaningful billowing or pumping effect from walking on it but that was a very good thought that you had and is worth keeping in mind for other situations.

I think that if the existing floor surface is reasonably flat and smooth it's better just to lay the resilient directly on top of the primed surface.

That'll make later removal of all of those flooring layers easier.

If necessary you can tack down a quarter round molding around the edges of the floor.

On 2022-07-23 by Jonny

Hi, useful resource here. Thanks for compiling. We're getting ready move into into our second pre-80's project house. This one I was much smarted and bulk sampled before doing anything.

The one big query is the best approach for the vinyl flooring backing. The previous owner at some point tried to update the kitchen/dining flooring and has installed laminate to part of it but the entire dining room is bare vinyl backing and the wear layer has been pulled off. I assume this is the same situation under the floating laminate in the kitchen.

Gathering a sample of this shows that its is incredibly tenaciously stuck down to the wood sub floor. It tests as 30% asbestos content. We wont be ready to remediate this or drywall for a good year so have to live in the house in the mean time. The end plan might be hydronic infloor hear with a polished concrete surface

As I have no idea how long the backing has been exposed, what cleaners or potential bond breaking mess has been applied to the floor, I'm unsure what my best approach is to encapsulate this? Some kind of high adhesion primer like guardz/BIN etc then a decent wear layer paint?

Perfectprimer is not available in my location unfortunately

Or straight to a 3/8 ply glued over top - however this may need to be removed later depending on future flooring which then poses further risk due to all the screw penetrations disturbing the backing. I would also likely pull the laminate and deal with this also as I'm conscious that foot traffic over a floating floor could produce a billow effect and push "contaminated" air from under laminate floor.

thanks in advance for any insight!

On 2022-06-02 by InspectApedia-911 (mod)

@Erin Howell,

It's a little hard to see but I think the upper right corner of your photo is showing a light colored "corkstyle" floor tile - quite commonly containing asbestos in the 1950s - 70s.

Use the on page search box to find "CORKSTYLE FLOOR TILES" to do some comparisons.

Your plan sounds exactly right.

On 2022-06-02 by Erin Howell

This is an 1920’s house, multiple layers of flooring. We are ripping up the top and and under it is this- does this look like it contains asbestos? There are two types of tiles. We planned to put subfloor down, then vinyl over that.

On 2022-03-20 by Inspectapedia Com Moderator - can I remove ceramic tile over asbestos flooring?

@CSco,

If you can remove the ceramic floor tile without disturbing the suspected vinyl asbestos or asphalt asbestos floor tile beneath it, then that will be fine.

However that may not be the case, depending on how much of the ceramic tile adhesive you need to remove before laying your new flooring.

On 2022-03-20 by CSco

We've got an offer in on a house built in 1964. Based on records, it most likely had asbestos tile. Ceramic tile (that we do not like) was installed in 2014, but we have no way of knowing if it was laid OVER asbestos tile. We don't want to keep the ceramic tile. Can we safely remove the ceramic tile if it was installed over asbestos tile?

On 2022-03-17 by Inspectapedia Com Moderator - black mastic under asbestos sheet flooring

@Britt,

Try to feel a bet less panic over this question - as that may be more of a health risk than the flooring.

The floor is not highly friable unless being demolished; While running a conventional vacuum cleaner over it isn't a great idea (a HEPA vacuum would be ok), and while nobody can possibly guess at the actual exposure a person had to airborne dust based on just a text and a photo, it's not likely that you'll develop asbestosis from the situation you described.

You should of course take your question to your doctor, a doc whom you trust, and listen to her advice. \

Keep in mind that the egregious cases of asbestosis occurred in workers in industrial settings, and perhaps in their families: people who worked in areas where there was so much airborne asbestos that the air was opaque or milky white making it difficult even to see.

Please post or give us links to the 1939 catalog that featured the flooring in your photo.

And then follow the standard advice for reducing the hazard: cover the flooring with new material.

On 2022-03-17 by Britt

I moved into a house where there is asbestos sheet flooring, to which my landlord disclosed. My entire attic floor is made with it, and the home was built in the 1920s. I seems to have found the type in an old 1939 catalog.

Anyways, I unknowing about the risk at the time, taped down large chunks that were sitting loosely on top of hard wood planks for flooring. I also vacuumed before I taped the pieces to each other. After learning more about the dangers, I am seriously freaked out. It seemed to have that black stuff underneath the tiles and I read its super dangerous.

My question is, how do I know if ill develop diseases now? Is there any way to find out even though it was minor? Also, my floor is cracking severely in some spots, and curling on some joints. I sleep close to the floor, is this a real threat?

On 2021-10-21 by inspectapedia.com.moderator - dance studio has 9x9 vinyl tile flooring

@Steve,

Asbestos is safe and legal to remain in homes or public buildings as long as the asbestos materials are in good condition and the asbestos can not be released into the air.

Generally the safest approach is to leave such flooring alone and to cover it with a coating or with another layer of flooring. If the flooring has deteriorated to the point of being friable, then the solutions are different. It doesn’t sound like that’s the case for the dance studio.

Above on this page, we describe using an epoxy coating or a few replacement tiles on a floor in generally good condition and provided that the remaining floor tiles are well-adhered to the floor below.

You can also read more about leaving asbestos floor tiles in place at:

REDUCE THE HAZARD OF ASBESTOS FLOOR TILES

On 2021-10-21 by Steve

Hi, my daughters dance studio has 9x9 vinyl tile flooring. I noticed one or two chipped tiles and brought it to the owners attention that they may contain asbestos. She got them checked out and one of the 3 samples tested positive for containing 3% asbestos. All of the mastic samples came back negative.

The company she is working with on it said that given the relative good condition of the floor and the mastic being negative and only 3% asbestos in the tile there is really no health risk and she can leave the floor as is, covering the two chipped tiles with the dance mat (lays over the floor not permanent covering). The floor looks to be in decent shape but old and dusty/faded a bit but not broken apart of crumbling by any means.

My question is given the wear and tear of hosting dance classes, including tap dancing in that space even on the dance mat, is it true that it is still unlikely to pose a health risk leaving the floor as is? I confirmed the company she is working with is properly licensed for asbestos testing and program management.

Question: what's the best way to finish cleaning these asbestos-tiled steps before painting with epoxy

...

2021/10/13 Anonymous by private email:

The pics below are from a home in Media, PA built in 1930. Not sure when the flooring was put on the basement steps. I removed the carpeting from the steps and revealed what looks like vinyl or linoleum underneath. I took the vinyl/linoleum flooring off of three steps before I thought about asbestos. The adhesive is brown and appears to be water soluble. I'm really freaked out now that I exposed my family to some nasty stuff.

Would it be safe to wet scrape the remaining adhesive off the steps before epoxy painting?

I plan to epoxy paint over the remaining vinyl/linoleum flooring after I remove the carpet on top of it. Does that make sense?

Moderator reply:

Treat the floor and mastic as presumed to contain asbestos if you're not going to have those materials tested.

I suggest taking a look at the advice at ASBESTOS FLOORING LEFT IN PLACE - (the article above on this page)

where we discuss using sealants and how we cleaned the surfaces first

but in general an epoxy paint will bond well to a secure, clean surface - as you'll see in that article.

I'm unclear why we're scraping - perhaps to try to leave a smooth-epoxy-painted surface? Ok,

then you might also want to see

ASBESTOS REMOVAL, WETTING GUIDELINES

Reader follow-up:

Yes, I was thinking of wet scraping the mastic because I wanted a smooth epoxy paint surface.

It seems like it would be safer to just epoxy paint over the remaining mastic after cleaning though right?

Moderator reply:

The nicest job would be to wet-scrape to give a smooth surface as you described, as in your case you intend to leave the epoxy painted surfaces exposed as the finished surface.

If I were planning to install flooring atop the old, cleaned surfaces, I'd simply use one of the asbestos sealant paints we describe in our article series and then install the new flooring.

On 2021-03-26 by (mod) - best way to fill in one or two missing tiles in an asbestos tile floor

@Chantal, thanks for a helpful question that I'd re-phrase as

What is the best way to fill in one or two missing tiles in an asbestos tile floor to be left in place and covered-over?

Simple solution-1: with the surface where the tile was lost is clean and free from oil or grease, simply glue down any floor tile of the right dimensions and of the same thickness as the originals.

Simple solutution-2: with the surface where the tile was lost is clean and free from oil or grease, and using a wide blade (8-12") drywall taping knife or blade, fill the low area with an adhering filler like Dash Patch or Durham's Rock Hard Water Putty. You can see photos of those products at https://inspectapedia.com/interiors/Fiberboard-Panel-Repair.php FIBERBOARD PANEL REPAIR

At https://inspectapedia.com/interiors/Floor-Tile-Base-Leveling.php FLOOR TILE BASE LEVELING we discuss using fillers and leveling compound to fill in the spots where a floor tile has been lost or removed.

Also see https://inspectapedia.com/hazmat/Asbestos_Floor_Sealants.php FLOORING ADHESIVE MASTIC SEALANTS - if you need to glue down new floor or add a leveling compound over old tile mastic

Also see https://inspectapedia.com/hazmat/Asbestos_Floor_Sealants.php FLOORING ADHESIVE MASTIC SEALANTS - if you need to glue down new floor or add a leveling compound over old tile mastic and where you're worried that old exposed mastic may prevent adhesion of new flooring.

On 2021-03-26 by Chantal

I want to install vinyl tile over existing asbestos tiles. All tiles are in good condition except for one. What product would be good to patch the one broken tile so that the floor is level?

On 2020-10-27 by (mod) - sealants & new flooring layer over asbestos-suspect flooring mastic adhesive - DIY Asbestos abatement, Chrysotile hazards?

George

In my opinion, any covering flooring that is continuous and secure ought to minimize the risk of remaining mastic on your floor, especially if under the engineered flooring you describe you've already got a layer of primer.

Nobody can know for a fact what an un-built anything is going to do, but in general, in my OPINION, the combination of covering the remaining mastic with primer and then with an interlocking plank flooring means that there ought to be minimal movement to disturb the mastic and even less possibility of those particles moving up into the occupied space.

Add to that that mastic, an asphaltic coating that contained asbestos fibres, is not normally friable.

On 2020-10-27 by George - Rather than hire an asbestos abatement company I did it myself

I have a small 10’ x 12’ room that had 9” x 9” asbestos tiles. I had the tiles and mastic tested at a lab. Results came back 1-3% Chrysotile, 0% Amosite in the black mastic, and 2-3% Chrysotile, 0% Amosite in the tile.

Rather than hire an abatement company I did it myself, and perhaps took more precautionary measures than necessary due to it being only Chrysotile, and a low percentage at that with a short exposure time.

I sealed the entry door and air duct vent in the room with plastic, used a hazmat suit rated for asbestos work, wore a full face respirator with P100 filters, and opened the window (left open for 2 days).

Most of the tiles came up very easily, and some tiles were quite friable, as they crumbled fairly easily.

As I removed the tiles, I sprayed some of the smaller/crumbly pieces down with a water/dish soap solution to prevent dust, but it still got a little dusty in there. I then bagged up all the tiles and placed them in a garbage bin outside of the room's open window.

What was left was black mastic on a wood sub-floor. I put MBP Multi-Surface Bonding Primer (from Home Depot) over the mastic floor (see attached picture). I realized after the fact that I should've used "Perfect primer", but it's too late. The MBP primer after drying has a rough gritty texture to it. The product is actually intended for creating adhesion to ceramic tiles or other cement-based flooring.

To my question...

I want to clarify what I read above on this page that: I can put floating Vinyl Plank Flooring over the wood floor that has the black mastic over it. Will this provide adequate protection from the mastic underneath? I will also be putting a layer of interlocking gym padding over the vinyl planks so that we may use the room as a home gym.

Here is a link to a white paper and the most informative document I have found regarding health risks from different types of asbestos, particularly, Chrysotile:

• Bernstein, David, Jacques Dunnigan, Thomas Hesterberg, Robert Brown, Juan Antonio Legaspi Velasco, Raúl Barrera, John Hoskins, and Allen Gibbs.
  
  HEALTH RISK OF CHRYSOTILE REVISITED [PDF] Critical reviews in toxicology 43, no. 2 (2013): 154-183.
  Abstract:
  
  This review provides a basis for substantiating both kinetically and pathologically the differences between chrysotile and amphibole asbestos.
  
  Chrysotile, which is rapidly attacked by the acid environment of the macrophage, falls apart in the lung into short fibers and particles, while the amphibole asbestos persist creating a response to the fibrous structure of this mineral.
  
  Inhalation toxicity studies of chrysotile at non-lung overload conditions demonstrate that the long (>20 µm) fibers are rapidly cleared from the lung, are not translocated to the pleural cavity and do not initiate fibrogenic response. In contrast, long amphibole asbestos fibers persist, are quickly (within 7 d) translocated to the pleural cavity and result in interstitial fibrosis and pleural inflammation.
  
  Quantitative reviews of epidemiological studies of mineral fibers have determined the potency of chrysotile and amphibole asbestos for causing lung cancer and mesothelioma in relation to fiber type and have also differentiated between these two minerals.
  
  These studies have been reviewed in light of the frequent use of amphibole asbestos. As with other respirable particulates, there is evidence that heavy and prolonged exposure to chrysotile can produce lung cancer. The importance of the present and other similar reviews is that the studies they report show that low exposures to chrysotile do not present a detectable risk to health.
  
  Since total dose over time decides the likelihood of disease occurrence and progression, they also suggest that the risk of an adverse outcome may be low with even high exposures experienced over a short duration.
  
  Keywords: Amphibole asbestos, cement products, chrysotile, epidemiology, health risk, inhalation toxicology, mining
  
  Thank you for any info you may have regarding my question / concern.

Really? We have provided a copy of the Bernstein et als article, above as a PDF download; See also the following comments that are quite critical of the article above and its conclusions - Ed.

• Bernstein, David, Jacques Dunnigan, Thomas Hesterberg, Robert Brown, Juan Antonio Legaspi Velasco, Raul Barrerao, John Hoskins, and Allen Gibbs.
  "RESPONSE to Murray M. Finkelstein, letter to the editor re Bernstein et al: Health risk of chrysotile revisited. Crit Rev Toxicol, 2013; 43 (2): 154–183." Critical reviews in toxicology 43, no. 8 (2013): 709-710.
  Excerpts:
  
  Surprisingly, Bernstein and colleagues completely ignored the human lung burden studies that refute their conclusion about the short biopersistence of chrysotile.
  
  [the authors then cite numerous works offering a different conclusion than Bernstein et als and conclude as follows:]
  
  The human data concerning chrysotile retention in occupationally exposed populations are thus inconsistent with the statement of Bernstein and colleagues that chrysotile has a short biopersistence, yet Bernstein and colleagues completely failed to mention these data.
  
  The Instructions for Authors planning to submit to Critical Reviews in Toxicology state that “Critical Reviews in Toxicology provides up-to-date, objective analyses of topics related to the mechanisms of action, responses, and assessment of health risks due to toxicant exposure.
  
  The journal publishes critical, comprehensive reviews of research findings in toxicology and the application of toxicological information in assessing human health hazards and risks”.
  
  By failing to mention any of the data which contradict their conclusions, Bernstein and colleagues have clearly not provided an objective analysis, and have created the impression that they have published a document to support the interests of the International Chrysotile Association, which, in cooperation with The Canadian Chrysotile Association, funded their work.

Really? and critical of the criticism:

• Bernstein, David, Jacques Dunnigan, Thomas Hesterberg, Robert Brown, Juan Antonio Legaspi Velasco, Raul Barrerao, John Hoskins, and Allen Gibbs. "Response to Murray M. Finkelstein, letter to the editor re Bernstein et al: Health risk of chrysotile revisited. Crit Rev Toxicol, 2013; 43 (2): 154–183." Critical reviews in toxicology 43, no. 8 (2013): 709-710.
  
  Excerpt:
  However, the data cited by Finkelstein do not contradict the concepts put forward by Bernstein et al. and in fact they appear in company with an understanding of the toxicology to clearly support these concepts.
  
  Finally, Finkelstein refers to the funding of the Bernstein et al. review by the Canadian Chrysotile Association, stating that “they have published a document to support the interests of the International Chrysotile Association”.
  
  In his own Declaration of Interest, Finkelstein declares that “The author has appeared as an expert witness in litigation concerned with alleged health effects of exposure to chrysotile”.
  
  What Finkelstein has left unstated is the frequency with which he works for the plaintiff’s lawyers who would benefit from publication of his Letter to the Editor.
  
  Declaration of interest
  
  The preparation of the original paper was supported by a fixed sum grant from the International Chrysotile Association, Washington, DC, USA, in cooperation with The Canadian Chrysotile Association, Montréal, QC, Canada. The affiliation of the authors includes university, government institute, hospital and corporate affiliations as well as independent toxicology consultants. This letter is the professional work product of the authors alone and may not necessarily represent the views of the corporate sponsors.
  
  Two of the authors, David Bernstein and Allen Gibbs have appeared as expert witnesses in litigation concerned with alleged health effects of exposure to chrysotile. Jacques Dunnigan has served as an expert witness on the health effects of chrysotile before the Commission de la santé et sécurité du travail du Quebec/Workers Compensation Board of Québec.
  

On 2020-07-30 by kkimee@sbcglobal.net

my asbestos flooring is damaged... What can I use to seal it before putting in new flooring? I'm lost in all the options on your site which seem to be geared towards asbestos flooring in good condition.Thank you

On 2020-02-20 by Jason FIner - Perfect Membrane sealer for asbestos-containing floor tiles or mastic adhesive

John,
You are correct that the floor must be clean and smooth with loose tiles removed. have been using perfectprimer for years for these applications. All I do is clean the floor s with some tsp solutions and water. Then apply two coats of perfectprimer.

If you want to apply some leveling agent, like rapid set or thin set etc, then apply it over the first coat perfectprimer, then apply the second coat of the primer over the entire floor and patched area.

Any paint or epoxy or mastic will bind with that and your finished.

If you need to do a full blown encapsulation or waterproofing system, then I use perfect membrane by the same company ( specialty Solutions)

On 2019-12-14 by (mod)

John

A typical cover-over job with new floor tiles atop old asbestos-suspect flooring requires that the existing surface be generally smooth and sound - that is, loose tiles are not popping up, and there are no abrupt dips or holes that might telegraph up through the new flooring.

If you're covering with a laminate or engineered wood or wood floor then those small imperfections are unlikely to have any effect whatsoever; you'd just lay down rosin paper or whatever underlayment or vapor barrier the new flooring manufacturer recommends, and proceed.

If you're covering the old floor with sheet vinyl, thin new vinyl floor tiles, or soft cork tiles, you may want to glue down replacement tiles of same thickness of any large sections of tile or flooring that are already missing, OR to use a floor leveling compound.

When your new floor is to be glued or adhered with tile mastic to the old one, the old surface needs to be clean of dust, debris (damp wipe, HEPA vacuum), and clean of any floor wax. I use a liquid stripping compound, NOT any abrasives. For this type of installation, several of the mold and fire and asbestos abatement coating manufacturers recommend products that bond well to the existing floor and are claimed to accept and bond well to the adhesive used on the new floor.

As we noted on this point in the article above

you may want to see ASBESTOS ENCAPSULANTS & SEALERS - coatings, encapsulants, fiber release control for asbestos containing materials

On 2019-12-1 by John

I removed carpet in a 10x12 room, found old vinyl tiles. Some of them are broken at the edges and some are loose. I intend to cover with new cork flooring. Before that I'd like to know if I should paint with something like fiber lock 2 or perfect primer, in case of asbestos. Sorry for the long post. Thank you.

...

Continue reading  at ASBESTOS FLOORING REMOVAL GUIDE or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

Or see ASBESTOS FLOORING LEFT IN PLACE FAQs - questions & answers posted originally at this page.

Or see these

Recommended Articles

• ASBESTOS-CONTAINING ADHESIVES
• ASBESTOS ENCAPSULANTS & SEALERS - coatings, encapsulants, fiber release control for asbestos containing materials
• ASBESTOS FLOORING HAZARD REDUCTION - home
• ASBESTOS FLOORING IDENTIFICATION
• ASBESTOS FLOORING HAZARD LEVEL ASSESSMENT
• ASBESTOS DISPOSAL REGULATIONS
• ASBESTOS FLOORING LEFT IN PLACE using an expoxy floor paint over asbestos-containing floor tiles or sheet flooring.
• ASBESTOS FLOORING REMOVAL GUIDE
• ASBESTOS REMOVAL, WETTING GUIDELINES
• DOES THIS FLOOR CONTAIN ASBESTOS? - 5 easy questions to tell if your FLOOR probably contains asbestos -
• FLOOR TILE BASE LEVELING describes using leveling compounds or filler-tiles before flooring-over asbestos tile floors
• FLOORING ADHESIVE MASTIC SEALANTS - if you need to glue down new floor or add a leveling compound over old tile mastic
• RESILIENT FLOORING VINYL or CORK installation

Suggested citation for this web page

ASBESTOS FLOORING LEFT IN PLACE at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.

Or see this

INDEX to RELATED ARTICLES: ARTICLE INDEX to ASBESTOS HAZARDS

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