Is there a definition of a “lead based paint hazard” under Local Law #1 of New York City?

Yes. It is defined as “any condition in a dwelling that causes exposure to lead contaminated dust from lead based paint that is peeling or from lead based paint that is present on chewable surfaces, deteriorated sub-surfaces, friction surfaces, or impact surfaces that would result in adverse human health effects.”(See Local Law #1 of 2004)