Wetting to Reduce Asbestos Particle Release Hazards

ASBESTOS REMOVAL, Wetting Guidelines - Asbestos NESHAP Adequately Wet Guidance for Asbestos Flooring Removal - Suggestions for reducing particle and dust release from asbestos-suspect floor tiles
ASBESTOS PIPE INSULATION - separate article
ASBESTOS REMOVAL GUIDE, FLOORING - separate article
ASBESTOS CEMENT ROOFING - home
ASBESTOS CEMENT SIDING - home
OSHA Regulations, Asbestos Roofing, Siding - separate article
Questions & Answers about safe practices during asbestos cleanup or removal
References

Click to Show or Hide Related Topics

InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.

How to Use Wetting to Reduce Asbestos Particle Release Hazards During Demolition or Removal: this article describes how to use wetting procedures to reduce asbestos particle hazards during the demolition or clean-up of building products that may contain asbestos. We cite authoritative government and expert sources on safe handling of asbestos-containing waste materials, expanding and illustrating original sources.

Asbestos NESHAP Adequately Wet Guidance for Asbestos Flooring Removal

This document 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. Readers dealing with asbestos-containing floor tiles or sheet flooring should also see ASBESTOS FLOORING HAZARD REDUCTION and ASBESTOS FLOORING REMOVAL GUIDE. For a strategy for collecting building dust samples, when, where, how many samples to collect, see DUST SAMPLING PROCEDURE.

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.

This document quotes [with minor formatting & editing for read-ability] from Asbestos NESHAP Adequately Wet Guidance, EPA340/1-90-019 [Asbestos NESHAP Adequately Wet Guidance, EPA340/1-90-019, December 1990, U.S. ENVIRONMENTAL PROTECTION AGENCY, Office of Air Quality Planning and Standards, Stationary Source Compliance Division, Washington, DC 20460,original web source: http://www.epa.gov/region04/air/asbestos/awet.htm]

This document was written by Alliance Technologies, Inc., based on discussions with a work group from EPA. The group consisted of the Regional Asbestos NESHAP Coordinators, Ron Shafer, Scott Throwe, and Omayra Salgado of the Stationary Source Compliance Division, Charles Garlow and Elise Hoerath of the Air Enforcement Division and Sims Roy of the Standards Development Branch. We thank the individuals who reviewed an earlier draft and provided comments, many of which are incorporated in the final version. Their input is gratefully acknowledged.

1. Introduction to Asbestos NESHAP Adequately Wet Guidance

The Clean Air Act (CAA) of 1970 requires the U.S. Environmental Protection Agency (EPA) to develop and enforce regulations to protect the general public from exposure to airborne contaminants that are known to be hazardous to human health. In accordance with Section 112 of the CAA, EPA established National Emissions Standards for Hazardous Air Pollutants (NESHAP) to protect the public. Asbestos was one of the first hazardous air pollutants regulated under Section 112. The Asbestos NESHAP (40 CFR 61, Subpart M) addresses milling, manufacturing and fabricating operations, demolition and renovation activities, waste disposal issues, active and inactive waste disposal sites and asbestos conversion processes.

The Asbestos NESHAP requires facility owners and/or operators involved in demolition and renovation activities to control emissions of particulate asbestos to the outside air because no safe concentration of airborne asbestos has ever been established. The primary method used to control asbestos emissions is to adequately wet the Asbestos Containing Material (ACM) with a wetting agent prior to, during and after demolition/renovation activities.

The purpose of this document is to provide guidance to asbestos inspectors and the regulated community on how to determine if friable ACM is adequately wet as required by the Asbestos NESHAP.

The recommendations made in this guidance are solely recommendations. They are not the exclusive means of complying with the Asbestos NESHAP requirements. Following these recommendations is not a guarantee against findings of violation. Determinations of whether asbestos materials are adequately wetted are made by EPA inspectors on site.

2. Important Terms in Asbestos NESHAP Adequately Wet Guidance

Adequately Wet

EPA defines "adequately wet" to mean "sufficiently mix or penetrate with liquid to prevent the release of particulates. If visible emissions are observed coming from asbestos-containing material (ACM), then that material has not been adequately wetted. However, the absence of visible emission is not sufficient evidence of being adequately wet (Section 61.141,Definitions). Amended water is often used to wet ACM during repair/removal operations.

Friable Asbestos Material

Friable asbestos material is any material containing more than 1 percent asbestos as determined using Polarized Light Microscopy (PLM), that, when dry, can be crumbled, pulverized, or reduced to powder by hand pressure.

Asbestos-Containing Waste Materials (ACWM)

EPA defines ACWM to mean mill tailings or any waste that contains commercial asbestos and is generated by a source subject to the provisions of this subpart. This term includes filters from control devices, friable asbestos waste material, and bags on other similar packaging contaminated with commercial asbestos.

As applied to demolition and renovation operations, this term also includes friable asbestos waste and Category II non-friable ACM waste that becomes crumbled, pulverized, or reduced to powder by forces that acted on the material during the course of demolition and renovation operations regulated by this subpart, and materials contaminated with asbestos including disposal equipment and clothing.

non-friable Asbestos-containing Materials

non-friable asbestos-containing material is any material containing more than 1 percent asbestos as determined using Polarized Light Microscopy (PLM) that, when dry, cannot be crumbled, pulverized, or reduced to powder by hand pressure.

Regulated Asbestos-Containing Material (RACM)

Is (a) friable asbestos material, (b) Category I non-friable ACM that has become friable, (c) Category I non-friable ACM that will be or has been subjected to sanding, grinding, cutting or abrading, or (d) Category II non-friable ACM that has a high probability of becoming or has become crumbled, pulverized, or reduced to powder by the force expected to act on the material in the course of demolition or renovation operations.

3. Friable & Non-friable Asbestos-Containing Materials: Definitions

The Asbestos NESHAP defines two categories of non-friable ACM: Category I non-friable ACM (asbestos-containing packings, gaskets, resilient floor covering and asphalt roofing products) and Category II non-friable ACM (any non-friable material not designated as Category I).

The Agency requires that, where the Asbestos NESHAP is applicable, friable ACM and Category II and non-friable ACM that is likely to become disturbed or damaged so that the material could be crumbled, pulverized or reduced to powder during a demolition or renovation be removed, from a facility prior to its demolition/ renovation. The fibrous or fluffy spray-applied asbestos materials found in many buildings for fireproofing, insulating, sound-proofing, or decorative purposes are generally considered friable. Pipe and boiler wrap found in numerous buildings is also considered friable.

non-friable ACM, such as vinyl-asbestos floor tile, generally emits low levels of airborne fibers unless subjected to burning or to sanding, grinding, cutting or abrading operations. Other materials, such as asbestos cement sheet and pipe, can emit asbestos fibers if the materials are crumbled, pulverized or reduced to powder during demolition/renovation activities. Whenever non-friable materials are going to be damaged to the extent that they are crumbled, pulverized or reduced to powder, they must be handled in accordance with the Asbestos NESHAP.

4. Requirements for Adequately Wetting Asbestos-Containing Materials

The NESHAP regulation requires that RACM be adequately wetted during the following activities:

a. During cutting or disjoining operations when a facility component which is covered or coated with friable ACM is being removed from that facility as units or in sections (Section 61.145 (c)(2)(i)).

During demolitions or renovations a contractor may choose to remove an entire boiler, a section of pipe, or other facility components without first removing the asbestos insulation from these structures. Any ACM which will be disturbed during cutting or disjoining operations must be adequately wet.

b. During stripping operations when a facility component containing RACM remains in place in the facility. (Section 61.145 (c)(3)).

Stripping operations are the most common form of asbestos removal during renovation activities, since most items that are covered with asbestos are facility components or structural members which will not be removed. Stripping off all of the RACM can generate significant asbestos emissions if the ACM is not adequately wet during removal.

Friable spray-on ACM, which includes fire-proofing materials found on decking and support I-beams, is normally easy to wet throughout because of the absorbing property of the cellulose mixing/binding agent. The Asbestos NESHAP requires that these materials be fully penetrated with the wetting agent during demolition/renovation activities.

Other ACM, however, such as "thermal-block" insulation used on pipes and boilers, certain ceiling and floor tile applications, etc., which do not absorb water readily may be hard to penetrate by water or a wetting agent. For such materials, adequate wetting consists of coating the surfaces of the materials with water or a wetting agent prior to, during, and, in most cases, after removal activities in order to prevent asbestos emissions. Whenever such materials are broken during the removal process, the exposed, dry surfaces must be wetted immediately to reduce emissions.

If pieces of dry ACM are accidentally disturbed, they should be immediately wetted and kept wet until collected for disposal. Removal personnel are commonly assigned to keep the fallen RACM wet prior to its being collected for disposal.

c. After the RACM has been stripped from a facility component, it must remain adequately wet until it has been collected and contained or treated in preparation for disposal. (Section 61.145 (c)(6)(i)).

After removal, adequately wetted ACWM must be sealed in leak-tight containers or wrapping which must be labeled as specified by the Occupational Health and Safety Administration (OSHA) under 29 CFR 1910.1001(j)(2) or 1926.58(k)(2)(iii). Such waste materials destined for off-site transport must additionally be labeled with the name of the generator and location of the waste generation site (Section 61.150 (a)(1)(iv and v)).

d. In demolitions where the RACM was not removed prior to demolition (Section 61.145 (c)(1)(i)(ii)(iii)(iv)).

RACM on a facility component encased in concrete or other similarly hard material must be adequately wet whenever exposed during demolitions (Section 61.145 (c)(1)(ii));

RACM which was not accessible for testing and, due to demolition, cannot be safely removed, must be kept adequately wet at all times until disposed of (Section 61.145 (c)(1)(iii)):

The portion of a facility ordered demolished that contains RACM must be adequately wet during the wrecking operation (Section 61.145 (c)(9)).

In each of the above situations, ACWM generated must be kept adequately wet during handling and loading for transport to the disposal site. In cases where ACWM can't be segregated from the debris pile it must be disposed of as ACWM. Such ACWM does not have to be sealed in leak-tight containers or wrapping, but may be transported and disposed of in bulk (Section 61.150 (a)(3)).

5. Exceptions to Wetting Asbestos Containing Materials During Demolition or Renovation

The Asbestos NESHAP allows two exceptions to wetting RACM during a demolition or renovation project:

When the temperature at the point of wetting is below 0C (32F) (Section 61.145 (c)(7)(i)). The owner/operator must remove facility components coated or covered with friable ACM as units or sections to the maximum extent possible and meet subsequent requirements of 61.145, including the wetting requirements. During periods when wetting operations are suspended due to freezing temperatures, the owner/operator must record the temperature in the area containing the facility components at the beginning, middle, and end of each workday and keep daily temperature records available for inspection by the Administrator during normal business hours at the demolition or renovation site. The owner or operator shall retain the temperature records for at least 2 years.

When the use of water would unavoidably damage equipment or present a safety hazard (Sec. 61.145 (c)(3)(i)(A)). The owner/operator must first obtain written approval from the Administrator for an alternative work practice, prior to renovation activities and utilize a local exhaust ventilation and collection system designed to capture particulate asbestos released during removal operations. (Section 61.145 (c)(3)(i)(B)(1)); or a glove bag system or a leak-tight wrapping which can contain the particulate asbestos materials produced by stripping ACM. (Section 61.145 (c)(3)(i)(B)(2)and (3))

6. Techniques Used for Wetting Asbestos-Containing Materials

General Information

Adequate wetting of ACM is typically accomplished by repeatedly spraying it with a liquid or a wetting agent, usually amended water (water to which surfactant chemicals have been added), until it can absorb no more. However, this does not necessarily mean that the ACM will be soaked throughout. Surfactant chemicals reduce the surface tension of the water, thereby increasing its ability to penetrate the ACM and surround the asbestos fibers.

Although amending agents are not required by the Asbestos NESHAP (the NESHAP only requires the use of a liquid), EPA, in its "Guidance for Controlling Asbestos-Containing Materials in buildings", EPA-560/5-85-024 (Purple Book), recommends the use of a 50:50 mixture of polyoxyethylene ester and polyoxyethylene ether, or the equivalent, in a 0.16 percent solution (1 ounce to 5 gallons) of water.

Wetting agents may be applied with garden sprayers or hoses. Garden sprayers are hand-held, portable, and have a one- to five-gallon capacity. Water hoses are usually attached to a faucet tap, fire hydrant or water tank. Generally, the hose has a nozzle attached which spreads the water stream so that a fine mist is created.

An engineering control often used is a misting unit which can be used to create a high level of humidity within a removal area. It is believed that fibers emitted into a saturated environment will absorb the wetting agent and fall out of the air faster, thus reducing airborne fiber levels.

7. Procedures for Wetting Asbestos Containing Materials

The following procedures describe methods of adequately wetting various applications of ACM.

Thermal System Insulation

Molded Pipe Insulation containing asbestos

The recommended wetting procedure for this type of RACM is to saturate the outer surface with amended water, strip off the wet canvas coating and then re wet the surface in order to thoroughly saturate the ACM. The metal bands supporting the RACM should be removed and the half-round sections carefully separated. While this occurs, the interior side and edges of the sections should be saturated with amended water.

If a section breaks during removal, the exposed surfaces should be wetted immediately. A misting sprayer may also be used to keep the air in the removal area or containment area saturated with amended water to attempt to reduce airborne asbestos fiber levels.

Corrugated Paper Pipe Insulation

The outer surface of the corrugated paper ("air-cell") pipe insulation, usually a canvas wrap, should be saturated with a wetting agent and then removed. Wetting should continue until all the insulation is permeated with amended water. Metal bands holding the insulation in place should be removed and the corrugated RACM insulation stripped.

Any unsaturated surfaces exposed during the stripping operation must be wetted immediately to reduce asbestos emissions. A misting sprayer may also be used to keep the air in the removal area saturated with amended water to attempt to reduce airborne asbestos fiber levels. Inadequately wetted and adequately wetted corrugated paper pipe insulation can be seen in Figures 1 and 2.

Figure 1. Inadequately wetted corrugated paper, pipe insulation. (Note the fibrous material adjacent to the lagging clamp.)

[FIGURE] - missing

Figure 2. Adequately wetted corrugated paper, pipe insulation. (Note the saturated material adjacent to the lagging clamp.)

[FIGURE] - missing

Boiler and Water Tank Thermal Block Insulation

Asbestos-containing preformed block insulation has been used as thermal insulation on boilers, hot water tanks and heat exchangers in industrial, commercial, institutional and residential applications. The blocks are commonly chalky in nature and may be held in place by chicken wire or expanded metal lath. A plaster-saturated canvas was often applied as a final covering or wrap.

Due to the number, thickness and varying absorbencies of these layers of materials, adequate wetting may be accomplished only by continually wetting the materials with amended water as the various layers are stripped.

One person may be assigned to spray the materials as they are stripped, and a misting sprayer may be used in an attempt to reduce airborne asbestos fiber levels.

Cementitious Fitting Insulation

Wetting of cementitious fitting insulation is similar to that used when removing asbestos-containing thermal block insulation. The outer surface is saturated with amended water and the outer covering (if applicable) is removed. The fitting insulation is then re wetted and the insulation stripped. To ensure that the fitting remains adequately wet during the removal operation, a person is often assigned to spray the ACM as it is stripped. A misting sprayer may be used to reduce airborne asbestos fiber levels. Inadequately wetted cementitious fitting insulation can be seen in Figure 3.

Figure 3. Inadequately wetted cementitious fitting insulation. (Note that the part of the insulation which has been wetted is dark grey in color, whereas the dry section remains white.)

[FIGURE] -missing

Asbestos-Containing Surfacing Materials

"Surfacing Material" is a generic term designated by the Asbestos Hazard Emergency Response Act (AHERA; Asbestos Containing Materials in Schools, 40 CFR Part 763, Subpart E) to mean any wall or ceiling material that is sprayed-on or troweled-on, such as acoustical plaster or fireproofing. The recommended wetting method for this type of RACM is to saturate the surfaces, begin the stripping operation and continue to wet the RACM as it is being removed.

A misting sprayer may also be used to keep the air saturated while the removal occurs. Since surfacing materials vary in their ability to absorb a wetting agent, inspectors must consider the type of surfacing material that is being removed in order to determine the required extent of penetration by the amended water. Surfacing materials which easily absorb a wetting agent need to be fully penetrated or permeated to be considered adequately wet, whereas only the exposed surfaces of materials which do not absorb water readily need to be wetted.

The use of high pressure water to remove asbestos-containing surfacing materials, either through a steam-cleaning device or a diesel powered hydroblasting water applicator, should be avoided since such use may unduly disturb RACM and contribute to higher airborne asbestos fiber levels. However, if this removal method is used, contractors must adequately wet the ACM prior to and during the removal.

Miscellaneous Asbestos-Containing Materials

Both friable and non-friable forms of other asbestos-containing building materials exist. Friable materials include asbestos-containing paper (commonly found beneath wooden floors), wallpaper, and joint compound. It has been estimated that 5 to 10 percent of the ceiling tiles currently installed in the U.S. contain asbestos.

Non-friable miscellaneous ACM includes floor tiles, asbestos cement sheet (transite board), siding shingles, asphalt roofing shingles, laboratory bench tops and even chalkboards. These materials may become friable with age, and under harsh conditions. Category I non-friable ACM must be carefully examined to determine if the material is in poor condition, that is, if the binding material is losing its integrity, exhibited by peeling, cracking or crumbling; and is also friable. When Category I non-friable ACM has become friable it is subject to the NESHAP.

If Category I or II ACM is sanded, ground, cut or abraded it is also covered by the NESHAP. Category II non-friable ACM which is damaged to the extent that it has or will become crumbled, pulverized or reduced to powder due to demolition/ renovation activities, is subject to the Asbestos NESHAP.

Miscellaneous materials are wetted in manners similar to those used to wet other categories of RACM. Coverings are saturated with a wetting agent before removal and the asbestos-containing portions fully penetrated with the agent prior to, during and after their removal, while stored in the removal area, and while being placed into disposal containers. Miscellaneous materials that don't absorb water readily (e.g., asbestos-concrete products, and floor tiles) are only required to have wetted surfaces. A misting sprayer may be used to diminish airborne asbestos fiber levels.

8. Inspection Procedures re Asbestos NESHAP Adequately Wet Guidance

The intent of the following guidelines is to provide GUIDANCE ONLY, to the regulated community regarding the inspection procedures recommended to Asbestos NESHAP inspectors for determining compliance with the "Adequately Wet" requirements of the Asbestos NESHAP.

The purpose of the wetting provisions for asbestos containing materials is to require as much wetting as is necessary to prevent airborne emissions of asbestos fibers. In order to achieve this result, RACM and ACWM must be wetted and maintained wet until collected for disposal. The determination of whether RACM or ACWM has been adequately wetted is generally based on observations made by the inspector at the time of inspection.

Observations probative of whether a material is adequately wet include but are not limited to, the following:

Is there a water supply in place?

Is water or a wetting agent observed being sprayed onto the RACM or ACWM both during stripping or removal and afterwards while the material awaits proper disposal? If yes, carefully note the method of application used (e.g., misting, fogging, spraying of surface area only or drenching to penetrate the ACM throughout).

If water or a wetting agent is being used, what equipment is used to apply it (e.g., garden hose, plant mister)?

If water or a wetting agent is not being used, determine why it is not and document the reason. Possible (although not necessarily valid) reasons include:

prior permission obtained from the Administrator (safety hazard, potential equipment damage);
no water source at the facility;
temperature at the point of wetting below 32 degrees F;
portable water supply ran out and contractor continued to work; or
contractor prepared the area earlier, etc.

Examine a stripped or removed piece of ACWM or RACM which wets readily. Does it appear to be wetted throughout? If it does not, adequately wet the sample. Describe and photograph how the physical characteristics of the material change upon wetting (e.g., color, weight, texture, etc.). Take samples, as necessary, to document the presence of asbestos in the suspect material.
When examining materials that do not readily absorb water or a wetting agent (e.g., pre molded thermal system insulation, ceiling tiles, floor tiles) inspectors should note whether all exposed surfaces of these materials have been wetted as required.
Is there visible dust (airborne or settled), or dry ACWM debris in the immediate vicinity of the operation? Inspectors should collect samples of such materials for analysis of their possible asbestos content.
Examine ACWM in bags or other containers using the procedures that follow, to determine if the material has been adequately wetted?

Randomly select bags (or containers) for inspection.

Lift the bag or container and assess its overall weight. (A bag of dry ACWM can generally be lifted easily with one hand, whereas a bag filled with well-wetted material is substantially heavier.)

If the bag or other container is transparent:

Visually inspect the contents of the unopened bag for evidence of moisture (e.g., water droplets, water in the bottom of the bag, a change in the color of the material due to water).]
Without opening the bag, squeeze chunks of debris to ascertain whether moisture droplets are emitted.
If the material appears dry or not penetrated with liquid or a wetting agent, open the bag using the additional steps described in step 9 below a collect a bulk sample of each type of material in the bag noting variations in size, patterns, color and textures.

If the waste material is contained in an opaque bag or other container, or if the material is in a transparent bag which appears to be inadequately wetted:

Carefully open the bag (in the containment area, if possible). If there is no containment area at the site, a glove bag may be used to enclose the container prior to opening it to minimize the risk of any fiber release.
Examine the contents of the bag for evidence of moisture as in 8 above, and if the material appears dry or it is not fully penetrated with water or a wetting agent, collect a bulk sample.
Reseal the bag immediately after evaluating and sampling its contents.

Frequently Asked Questions (FAQs)

...

Ask a Question or Search InspectApedia

Questions & answers or comments about safe practices during asbestos cleanup or removal

Ask a Question or Enter Search Terms in the InspectApedia search box just below.

Technical Reviewers & References

Related Topics, found near the top of this page suggest articles closely related to this one.

Asbestos NESHAP Adequately Wet Guidance, EPA340/1-90-019, December 1990, U.S. ENVIRONMENTAL PROTECTION AGENCY, Office of Air Quality Planning and Standards, Stationary Source Compliance Division, Washington, DC 20460,original web source: http://www.epa.gov/region04/air/asbestos/awet.htm
"Asbestos in your home or at work," Forsyth County Environmental Affairs Department, Winston-Salem NC 12/08
"Asbestos Floor Tile Removal", the University of Minnesota's advice on removing VAT (vinyl asbestos or asphalt asbestos floor tile) can be read in detail at www.health.state.mn.us/divs/eh/asbestos/floortile/index.html
Copy on file as - /hazmat/Asbestos_in_Your_Home_US_EPA.pdf - Asbestos in Your Home - U.S. EPA, Exposure Evaluation Division, Office of Toxic Substances, Office of Pesticides and Toxic Substances, U.S. Environmental Protection Agency, Washington,D.C. 20460
Resilient Floor Covering Institute, 1030 15th St. NW, suite 350, Washington D.C.
Asbestos regulations for schools (the Asbestos Hazard Emergency Response Act, "AHERA") (PDF) [on file as /sickhouse/EPA_Asebstos_Regulations.pdf ] - (96 pp, 589k), web search 08/17/2010, original source: http://www.epa.gov/asbestos/pubs/2003pt763.pdf,
Asbestos Regulations: State asbestos regulatory agencies (5 pp, 17k) (original source http://www.epa.gov/asbestos/pubs/statecontactsapril2009.pdf ) for information on how to find an accredited asbestos professional.
Managing Asbestos in Place: A Building Owner's Guide to Operations and Maintenance Programs ("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, quoting:
  
  Periodic Visual Re inspections and Air Monitoring
  
  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) [on file as /sickhouse/EPA_Asebstos_Regulations.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 re inspections
  EPA recommends a visual and physical evaluation of ACM during the re inspections to note the ACM's current condition and physical characteristics.
  
  Additional Prevention Measures
  - Supplemental Air Monitoring
    
    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 regulations at 29 CFR § 1910.1001(d).
  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.)
  
  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
  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
  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 and who follow EPA’s quality assurance guidelines. (See References, U.S. EPA, Dec. 1989, Transmission Electron Microscopy Asbestos Laboratories: Quality Assurance Guidelines. Washington, DC: EPA 560/5-90-002).
  - Selecting a Lab
    
    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, about 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) 975-4016.
Asbestos products and their history and use in various building materials such as asphalt and vinyl flooring includes discussion which draws on Asbestos, Its Industrial Applications, D.V. Rosato, engineering consultant, Newton, MA, Reinhold Publishing, 1959 Library of Congress Catalog Card No.: 59-12535 (out of print).
David Grudzinski, Advantage Home Inspections, is a professional home inspector in Cranston, RI. 02910. He can be reached at 401-935-6547, fax- 401-490-0607 or by email to contact/us@advantagehomeinspections.us 04/26/2009
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
The ABCs of Asbestos in Schools (August 2003), U.S. EPA, Web search 08/17/2010, original source: http://www.epa.gov/asbestos/pubs/abcsfinal.pdf - aqui se encuenta la misma documenta escrito en Espan~ol: El ABC del Asbestos en las Escuelas, fuente original: http://www.epa.gov/asbestos/pubs/spanishabcs.pdf
How to Manage Asbestos in School buildings, AHERA Designated Person Self Study Guide, U.S. EPA 910-B-96-001, January 1996, web search 08/17/2010, original source: http://www.epa.gov/region2/ahera/e23.pdf
EVER WEAR TILE CO is currently (2009) in the Terrazzo, Tile, Marble, and Mosaic Work industry in Fallon, NV. 775) 423-6221. [We do not know the company history nor whether there is an association with EverWear vinyl asbestos floor tiles discussed in this article.]
Thomas Hauswirth, Managing Member of Beacon Fine Home Inspections, LLC and (in 2007) Vice President, Connecticut Association of Home Inspectors Ph. 860-526-3355 Fax 860-526-2942 beaconinspections@sbcglobal.net 06/07: thanks for photographs of transite asbestos heating ducts
Gary Randolph, Ounce of Prevention Home Inspection, LLC Buffalo, NY, for attentive reading and editing suggestions. Mr. Randolph can be reached in Buffalo, NY, at (716) 636-3865 or email: gary@ouncehome.com 3/07
Asbestos Identification, Walter C.McCrone, McCrone Research Institute, Chicago, IL.1987 ISBN 0-904962-11-3. Dr. McCrone literally "wrote the book" on asbestos identification procedures which formed the basis for current work by asbestos identification laboratories.
Stanton, .F., et al., National Bureau of Standards Special Publication 506: 143-151
Pott, F., Staub-Reinhalf Luft 38, 486-490 (1978) cited by McCrone
Asbestos NESHAP Adequately Wet Guidance, EPA340/1-90-019, December 1990, U.S. ENVIRONMENTAL PROTECTION AGENCY, Office of Air Quality Planning and Standards, Stationary Source Compliance Division, Washington, DC 20460,original web source: http://www.epa.gov/region04/air/asbestos/awet.htm
Asbestos products and their history and use in various building materials such as asphalt and vinyl flooring includes discussion which draws on Asbestos, Its Industrial Applications, D.V. Rosato, engineering consultant, Newton, MA, Reinhold Publishing, 1959 Library of Congress Catalog Card No.: 59-12535 (out of print, text and images available at InspectAPedia.com).
EPA Asbestos Materials Bans: Clarification 1999
"Handling Asbestos-Containing roofing material - an update", Carl Good, NRCA Associate Executive Director, Professional Roofing, February 1992, p. 38-43
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
Copy on file as - /hazmat/Asbestos_in_Your_Home_US_EPA.pdf - Asbestos in Your Home - U.S. EPA, Exposure Evaluation Division, Office of Toxic Substances, Office of Pesticides and Toxic Substances, U.S. Environmental Protection Agency, Washington,D.C. 20460

Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair

Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.

The Home Reference Book - the Encyclopedia of Homes, Carson Dunlop & Associates, Toronto, Ontario, 25th Ed., 2012, is a bound volume of more than 450 illustrated pages that assist home inspectors and home owners in the inspection and detection of problems on buildings. The text is intended as a reference guide to help building owners operate and maintain their home effectively. Field inspection worksheets are included at the back of the volume. Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.

Or choose the The Home Reference eBook for PCs, Macs, Kindle, iPad, iPhone, or Android Smart Phones. Special Offer: For a 5% discount on any number of copies of the Home Reference eBook purchased as a single order. Enter INSPECTAEHRB in the order payment page "Promo/Redemption" space.

Building inspection education & report writing systems from Carson, Dunlop & Associates Ltd


	InspectAPedia^®	InspectAPedia
	Free Encyclopedia of Building & Environmental Inspection, Testing, Diagnosis, Repair	Ask a Question or Search InspectAPedia

Free Encyclopedia of Building & Environmental Inspection, Testing, Diagnosis, Repair

Ask a Question or Search InspectAPedia

Wetting to Reduce Asbestos Particle Release Hazards (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();