Definition of Lead Hazards

A paint is considered lead-based paint when any paint, varnish, shellac or other surface coating contains more than 5000 parts per million (ppm) by laboratory analysis.
A lead-paint hazard exists when any of the following conditions are true:

• Paint is deteriorated. {Deteriorated paint means any interior or exterior lead-based paint that is peeling, chipping, blistering, flaking, worn, chalking, alligatoring, cracking, or otherwise separating from the substrate, or located on any surface or fixture that is damaged.}
• Paint is being worn away on a friction surface, such as a window. {Friction surface is any interior or exterior surface subject to abrasion or friction such that it is contributing to the deterioration of lead-based paint or generating lead-contaminated dust.}
• Paint is being damaged by repeated impacts, such as on baseboards. {Impact surface is any exterior or interior surface subject to repeated impacts such that it is contributing to the deterioration of led-based paint or generating lead-contaminated dust.}
• Paint is on an accessible hazardous surface, such as a protruding interior windowsill, where children can mouth or chew on the surface. {Accessible hazardous surface is any exterior or interior surface that is accessible, mouthable, chewable, and by contact constitutes a lead hazard to children.}

Dust is considered contaminated when samples from surface dust contain lead equal to or exceeding 10 µg/ft2 on floors, 40 µg/ft2 on other interior horizontal surfaces, 100 µg/ft2 on interior windowsills, and 400 µg/ft2 on exterior windowsills and other exterior horizontal surfaces. (San Francisco Health Code, Article 26 and Title 17, Division 1, Chapter 8 of the California Code of Regulations, Toxics Substances Control Act, Section 403.)

When bare soil samples contain greater than or equal to 400 parts per million total lead, the soil is considered lead-contaminated.

Lead-contaminated water contains greater than or equal to 10 parts per billion (ppb) of lead.