Lead Paint, Lead Paint Removal
In the case of renovations involving lead abatement, contractors must also contact state health and environmental agencies to determine exact guidelines for the removal of lead-based paint.
while all unique, share one thing in common: the removal of materials that are no longer considered to be safe to consumers or the environment. Building products such as insulation, adhesives, metal and even plastic piping have come under the scrutiny of government and consumer groups to assure their safe use. Not unlike other building materials, paint and the raw materials used in its manufacture, has been researched for potential environmental and health risks. Lead, one of the raw materials contained in paint, was originally used as a pigment. The durable long-lasting qualities of lead-based paint made it advantageous to painters and their customers and its naturally bright white color provided an ideal base for tinting. But after research showed the harmful health effects of lead-based paint, especially in children, the federal government banned the product in 1978. Adults and children can get lead into their bodies by inhaling or ingesting dust or particles from lead-based paint.
To the professional painting contractor, safe and effective lead abatement is a critical part of the renovation process that must be done with great care in accordance with local and state regulations.
Before beginning the renovation of any job, careful evaluation of the site is necessary to determine special equipment and manpower needs. In the case of renovations involving lead abatement, contractors must also contact state health and environmental agencies to determine exact guidelines for the removal of lead-based paint. States also have various requirements and special certifications for contractors involved in lead abatement.
An important guideline that applies to contractors across the board is the distribution of the pamphlet Protect Your Family from Lead in Your Home. This publication provided by the federal EPA, CPSC and HUD is the result of a law passed in Congress in 1992. The pamphlet provides an overview of how lead-based paint can cause serious health problems. Information on checking family members for lead and how to check a home for lead hazards is included along with important phone numbers of regulating agencies.
According to the law, a copy of the pamphlet must be given to the owner or resident. Contractors must also get a signed acknowledgement from the customer that they have received the pamphlet.
One of the commonly asked questions in renovations is how to determine if lead-based paint is present. A common rule of thumb is to assume that any paint job completed in 1978 or before was done with lead-based paint since the product was not banned until then. Specialists in paint analysis can also determine if a surface has been coated with lead-based paint. Although some do-it-yourself kits for identifying lead-based paint are available, they are not usually accurate.
It is important to note that lead-based paint that is in good condition is usually not a problem. However, lead-based paint that is peeling, chipping, chalking or cracking is an immediate health hazard and needs to be addressed.
Lead abatement can be achieved in several different ways including: removing the lead-based paint through chemical stripping, encapsulation or surface enclosure. The first of these methods offers a broad range of options to the contractor. Products used for chemical stripping fall into three basic categories: caustics, safe removers (non-caustics), and solvents.
Caustics – These products contain either sodium hydroxide or potassium hydroxide as their stripping agent. Caustics are extremely effective in removing lead-based paint by “chemically melting” the coating. “Caustics are unparalleled when it comes to safely and efficiently removing up to 30 coats or more of lead-based paint with a single application,” says Hy Dubin, of Dumond Chemicals, Inc. Caustic removers are available in paste form and are applied with special spray equipment or by hand toweling. The product works by keeping the paint wet or damp during removal, which prevents the lead dust and particles from getting into the air or onto surrounding surfaces. When used properly, full containment procedures are not necessary. However, workers must keep their bodies covered (wear protective rubber gloves, safety glasses, head coverings, etc.) when working with these types of chemicals.
After application, follow manufacturers instructions on how long the paste needs to remain on the surface (dwell time) to effectively remove the paint. In general, dwell time can range between 12 and 24 hours. Once the lead-based paint has been stripped and removed along with the caustic paste, the substrate is rinsed with water to neutralize the surface and reduce the pH level.
Caustics can be used for interior or exterior work and have been used in industrial and historic renovation sites. These products are less effective in temperatures under 50 degrees Fahrenheit, but high humidity typically has little effect.
Caustic strippers can be used on a variety of substrates, but it is important to review the technical data from the manufacturer and conduct patch tests to determine if the removal system is appropriate for the substrate.
Safe or non-caustic removers - Safe removers usually contain chemicals like N-methyl-pyrrolidone (NMP) or dibasic esters (DBE). Safe removers work by breaking down the binders in the paint, causing it to dissolve or lift off the surface layer by layer. Similar to caustics, safe removers come in a paste or gel form which keep the paint wet during removal. By keeping the surface wet, the likelihood of creating lead chips or dust during removal is greatly reduced. “When used properly, lead dust exposure with non-caustic removers is well below the permissible exposure limit established by OSHA,” says Daniel Cohen of Back to Nature Products Company. In addition, some manufacturers of safe removers have developed strippers that not only safely remove lead paint, but also render the lead waste non-hazardous for disposal.
Safe removers are ideal for residential-type jobs although some are used on large-scale jobs as well. The product can be sprayed or applied with a brush or roller. As with any chemical stripper, it is important to refer back to manufacturer data sheets regarding specific details on removing the product. Like caustics, safe removers are used on a wide range of substrates and work on interior and exterior surfaces.
Solvents – This category of chemical strippers covers a wide range of products with active ingredients that differ from product to product. Widely marketed as do-it-yourself products, these chemical strippers are rarely, if ever, specified for lead abatement jobs of any size. Solvent-based removers are ideally used for small-scale projects where one or two layers of paint are being removed.
Another well-accepted method of lead abatement is encapsulation. Perhaps one of the most recent technical developments in lead abatement, encapsulation became an acceptable way to “remove” lead paint hazards when Congress passed the Residential Lead-based Paint Hazard Reduction Act (referred to as Title X) in 1992. This method involves the application of a paint-like coating over lead-based paint. Unlike surface preparation for non-lead based painted surfaces, great care is taken not to create dust.
Once the surface is dry and cleaned of debris, the specialized encapsulating coating is applied with a brush, roller or airless sprayer. When the new coating is dry, it forms a barrier that effectively encases the lead-based surface.
In order to be considered a true encapsulant, these specialized coatings must meet performance standards developed by the American Society for Testing and Materials (ASTM). An excellent overview of the requirements for a liquid encapsulant is described in Guidelines for the Evaluation and Control of Lead-based Paint Hazards in Housing (HUD, 1995). In summary, the liquid product must meet these criteria:
- Provide a 20-year warranty.
- Meet application guidelines as prescribed by the manufacturer.
- Patch testing must be completed successfully.
- The product must not contain toxic substances and must be capable of being applied safely.
- The encapsulant must adhere to existing paint films, and must remain intact for and extended period of time when exposed to normal wear and tear.
- The product and its application must comply with fire, health and environmental regulations.
The major advantages of using encapsulation as a means of abatement are lower costs than most lead removal procedures and ease of application. According to Andre Weker of Fiberlock Technologies, Inc., the application of encapsulants differs little from painting with ordinary paint. “The difference between the cost of a typical paint project and the cost of an encapsulation project is the slightly higher material cost for the encapsulant itself,” says Weker. “In fact, when you consider that encapsulation accomplishes both abatement and repainting simultaneously, encapsulation with a liquid coating is economically competitive with ordinary paint.”
Another method of abatement permitted by HUD and the EPA is enclosure. This process involves actually creating a physical barrier with sheetrock, paneling, siding or similar materials over the lead-based paint. In addition, all surfaces with the lead-based paint like doors, window frames, trim and molding must be removed and replaced. The major drawback of this method is the expense of replacing these materials in addition to losing attractive, one-of-a-kind architectural design features.
Lead abatement for any project is a major undertaking involving a number of circumstances that will impact the outcome of the project. To ensure success, nothing can replace strict attention to the details of the project while following the guidelines and laws of each state. Some basic considerations to keep in mind with each project:
- Timetable. Some methods of removal are faster than others: some require more dwell time, while others are more labor intensive. Reviewing the available abatement methods and what each requires will help determine which will work best.
- Historic guidelines. Historic buildings have strict guidelines to ensure that original architectural details remain intact. Contractors should investigate which abatement materials (chemical strippers, encapsulants) will do the required job without damaging the substrate.
- Substrate condition. Is the substrate itself in good enough condition to withstand abatement? In some cases total removal of the substrate is the only way to successfully get rid of the lead-based paint.
- Location. Is the job interior or exterior? When working on interior sites, some abatements will require full containment procedures and the evacuation of all occupants. On the other hand, some removal systems are specially designed to allow occupants to remain on site. In exterior lead abatement, contactors need to consider the containment apparatuses required for each method. For example, the use of some chemical strippers in lead abatement can control dust and waste to such an extent that containment may not be required.
The process of successfully completing lead abatement projects depends on the skill of the contractor, his workers, and the materials they use. The partnership between contractors and the technical expertise of manufacturers is also critical in lead abatement projects. Armed with these valuable assets along with following state and local regulations will guarantee your safety and a successful outcome.
|
