Next, powerful fans (called negative air machines) are brought in to pump air through High Efficiency Particulate Air (HEPA) filters and out of the work space. They also use water while working to keep dust down. All hazardous materials must be placed in double-layered hazardous waste bags and washed before being carried out of the work area.

Upon completion, they remove the plastic and dispose of it with the rest of the materials through a hazardous waste disposal company. Certified hazardous material abatement companies may be hired for removal only, but most are also licensed contractors equipped to complete the repair or remodeling project.

-- Tips courtesy of HomeAdvisor.com