A certification that a property is lead safe means that a certified EPA lead dust sampling technician has: determined the property is free of deteriorated, flaking, chipping, peeling, chalking or not-intact paint, and that interior dust samples were collected, tested, and found not to contain hazardous levels of lead-contaminated dust. A certificate will be given to each landlord and also sent to the City of Philadelphia as proof of compliance. This certificate is valid for 4 years.