Lead is a toxic material with a low melting point (621˚F) and boiling point (3164˚F). Lead fume generation starts when lead is heated to about 900˚F. The fume generation increases as the temperature increases. It is easy to see that welding or torch cutting on surfaces that contain lead will create lead fume. Welding or torch cutting on painted surfaces is something that should never be done.
Contractors are familiar with lead survey data that reports the lead level in paint in terms of milligrams per centimeter squared (mg/cm2). It is commonly assumed that 1mg/cm2 is approximately equivalent to 0.5% lead (lead paint definition). However, there is no direct correlation. To convert mg/cm2 to % lead it would be necessary to know the density and thickness of the paint. We have seen a lot of data that seems to use 1.0 mg/cm2 as a default reading. This data may be useful if the issue was whether the paint in question meets the legal definition of lead based paint. The information is of limited value when dealing with OSHA compliance issues. Compliance with the OSHA Construction Lead Standard requires that worker exposure sampling (industrial hygiene assessment) be done when any amount of lead is present. The paint analysis data should report levels of lead in paint that are substantially below the lead paint criterion of 1mg/cm2 (or approx. 0.5%). OSHA, for good reason, has regulated all detectable lead, not just "lead based paint". The fact that paint is not techinically “lead based paint” is irrelevant in terms of complying with the OSHA Construction Lead Standard. Many companies performing hazardous building materials assessments do not understand this.
We have found that paint with a lead concentration of less than 0.1% created lead fume that exceeded the OSHA Permissible Exposure Limit (PEL) of 50 ug/m3 while torch cutting. 0.1% lead is substantially below the commonly used definition of lead based paint of 0.5%.
Compliance concerns are not limited to welding and torch cutting. Grinding, cutting, drilling and general demolition work also may create lead issues. The likelihood of an over exposure diminishes when heat is not involved. However, other issues such as clothing, skin and work area contamination become more pronounced. Contamination of areas outside the work zone could cause major problems if lead containing dust escapes the contractor’s work space. These issues create mega problems because the allowable limits for the general population are substantially below OSHA requirements.
If you are faced with a lead standard compliance issue it may be difficult and time consuming to navigate the OSHA Construction Lead Standard. To reduce the hassle we have developed a simple Lead Standard Compliance Flow Chart that will provide information concerning the basic requirements of the standard. This flow chart is basic by design and does not include all the intricacies associated with full compliance. Reviewing the lead standard or discussing your compliance options with Cashins & Associates, Inc. is needed to fully understand all the compliance requirements.