There are many misunderstandings regarding building materials that commonly contain asbestos and lead. Proper education of the public is a valuable tool in minimizing the hysteria that often accompanies the public perception of both asbestos and lead. The purpose of this article is to minimize these misunderstandings but at the same time alert people to the characteristics of asbestos and lead that they should be concerned about.
Unlike most other environmental hazards, the mere presence of asbestos and lead in a home does not constitute a health hazard. It is the condition of the asbestos and lead that determines whether it should be removed or otherwise managed to prevent the possibility of a health hazard to the occupants of a home. In addition, if home renovations are planned, surveys of suspect asbestos containing materials and lead based paint should be undertaken by licensed individuals, (New York State Department of Labor certified asbestos inspector, EPA licensed lead inspector, with samples analyzed by a laboratory approved by the New York State Department of Health) with any required remediation/abatement activities performed by licensed asbestos abatement firms.
In the past, asbestos containing materials were commonly used in home construction. Suspect asbestos containing materials in residential construction typically included, but are not necessarily limited to: vinyl floor tiles and the underlying mastic; roofing materials; pipe insulation; boiler insulation; spray-on insulation; plasters; and ceiling/acoustical tiles. Vinyl floor tile and roofing materials are considered non-friable, meaning that they cannot be readily crumbled by hand pressure and the asbestos fibers are therefore less likely to become airborne, as compared to the friable forms of asbestos materials such as pipe insulation and spray on insulation.
If asbestos abatement is warranted, the actual abatement work and air monitoring should be performed by two independent firms. The air monitoring services should include a series of air clearance samples conducted after the asbestos abatement work is completed to ensure the adequacy of the remediation, as required by the Environmental Protection Agency and New York State Department of Labor. This independent air monitoring should not to be confused with air sampling performed by the asbestos abatement contractor to monitor their own employees' exposure as required by the Occupational Safety and Health Administration. Occupants of the residence should not be present during the abatement work since the highest potential exposure typically occurs during the actual asbestos abatement.
Until it was banned from residential use in 1978, lead-based paints were commonly used to finish both interior and exterior surfaces of homes and buildings. Lead-based paint can become a hazard when the condition of the paint deteriorates (peeling, chipping, cracking). Lead dust can form from painted surfaces that are subject to routine wear and tear (e.g., windows and window sills, doors and door frames, stairs, railings and banisters). Lead dust will also form when lead-based paint is sanded, scraped or heated. Sampling for suspect lead based paint is typically conducted by one of two methods: the collection of paint chip samples for laboratory analysis, or by real-time, direct-reading instrumentation using an X-ray fluorescence (XRF) instrument. XRF testing provides a more comprehensive evaluation, as the instrument is capable of detecting lead in multiple layers of built up paint.
Home remodeling or renovation work, if not conducted properly, can cause potential exposure to lead. Federal law requires that home remodeling contractors provide homeowners with information regarding lead exposure before
starting work. Common precautions to minimize the potential for exposure include not using belt-sanders, dry scrapers or dry sandpaper to remove lead-based paint and temporarily moving out of the house until the work is completed and the area is properly cleaned. Unlike air testing that is used to "clear" completed asbestos abatement projects, wipe samples are commonly used on lead abatement projects. Lead dust can remain in the home long after the work is completed. Collecting and analyzing wipe samples from surfaces where fine dust is likely to settle will provide a good indication as to the presence of lead dust.
Additional information for homeowners regarding potential asbestos and lead hazards can be found at the EPA web site (www.epa.gov).
Paul Debiase, C.I.H., C.S.P. is the department manager - Industrial Hygiene for H2M, Melville, N.Y. Tags: