In Massachusetts residential contractors who work on pre 1978 properties are required to obtain a RRP Lead Safe Renovation Contractor License. In addition so are residential landlords who own multifamily homes where they receive compensation in the form of rent. Many contractors who are registered with the EPA as Certified Firms HAVE NOT OBTAINED THEIR MASS LEAD SAFE RENOVATION CONTRACTOR LICENSE. WHY! OSHA Regulations in the Mass RRP Lead Law. OSHA Respiratory and Medical Monitoring Training