Mold Remediation

Fixing the Problem

  1. Before cleanup, stop the source of water. Otherwise, the mold will simply grow back.
  2. Use a disposable “Type N-95” respirator to limit your exposure to airborne mold. These are available at many hardware stores and on the internet: $12 - $25.
  3. If porous materials, like drywall or carpet and padding have been wet for longer than 48 hours, remove and dispose of those materials.
    • Porous materials like drywall tend to remain wet, especially the bottom portion, even after the source of water is gone. If drywall has been wet for longer than 2 days, remove the affected drywall approximately 3 feet up from the floor.
    • If removing drywall, isolate the room or rooms where the demolition is being performed with plastic, and use a fan to create negative pressure in the room.
  4. For non-porous materials (like bathroom tiles) and semi-porous materials (like wood), clean the materials. After the area is cleaned, dry it completely.
  5. If mold reappears, the source of water has not been eliminated.

Consider hiring an environmental health professional or industrial hygienist to define the problem and a trained contractor to clean it up. Checking references to make sure the contractor has experience cleaning up mold. Ask the contractor to follow the recommendations of one of the following:

Remediating Without a Specialist or Contractor

  1. Isolate the room or rooms where the demolition is being performed. Use plastic and a fan to create negative pressure in the room.
  2. Use respiratory protection (minimum of a N-95 disposable respirator), gloves, and eye protection.
  3. Ensure that the work area is not occupied.
  4. Cover the floor, doorways, and items left in the work area with plastic sheeting, and seal with tape.
  5. Shut down and seal air ventilation ducts/grills and other openings in the work area with plastic sheeting. Shut down the heating, ventilating, and air conditioning (HVAC) system to the area in order to properly seal vents.
  6. Avoid creating excessive dust (e.g. using power tools). Good practices include:
    • Cleaning or gently misting surfaces with a diluted soap or detergent solution prior to removal.
    • Using a high-efficiency particulate air (HEPA) vacuum attachment to collect dust.
    • Using a vacuum equipped with a HEPA filter.
  7. Remove and dispose of porous materials, like drywall or carpet and padding that have been wet for longer than 48 hours.

    • Porous materials like drywall tend to remain wet, especially the bottom portion, even after the source of water is gone. If drywall has been wet for longer than 48 hours, remove the drywall approximately 3 feet up from the floor.
    • Isolate the room or rooms where the demolition is being performed with plastic, and use a fan to create negative pressure in the room.

  8. Clean any moldy materials using a soap or detergent solution.
  9. Remove any materials in sealed plastic bags that cannot be cleaned:
    • Discard plastic sheeting after use.
    • There are no special requirements for disposal of moldy materials.
  10. HEPA-vacuum and clean with a damp cloth and/or mop and a soap or detergent solution any work areas used for egress.

Large Areas (100 square+ feet in a contiguous area – e.g. on separate walls in a single room)

  1. Hire professionals trained in the handling of mold-damaged materials. They should be equipped with:
    • A minimum of half-face elastomeric respirators with P-100 filters used in accordance with the OSHA respiratory protection standard (29 CFR 1910.134).
    • Full body coveralls with head and foot coverings.
    • Gloves and eye protection
  2. Contain the affected area:
    • Shut down the HVAC system to this area.
    • Isolate of the work area using plastic sheeting sealed with duct tape.
    • Remove furnishings.
    • Cover ventilation ducts/grills, any other openings, and remaining fixtures/furnishings with plastic sheeting sealed with duct tape.
    • Consider using an exhaust fan equipped with a HEPA filter to generate negative pressurization.
    • Consider using airlocks and a clean changing room.
    • Cover egress pathways if a clean changing room is not used.
  3. Ensure that the work area is unoccupied.
  4. Avoid any work practice that creates excessive dust. Use of power tools is not recommended. Good practices include:
    • Cleaning or gently misting surfaces with a diluted soap or detergent solution prior to removal.
    • If power tools are used, a high-efficiency particulate air  (HEPA) vacuum attachment should be used to collect dust.
    • Use a vacuum equipped with a HEPA filter at the point of any dust generation.
  5. Clean materials that can be cleaned with a soap or detergent solution (see mold cleaning page).
  6. Remove materials that cannot be cleaned in sealed plastic bags. Clean the outside of the bag with a damp cloth and a soap or detergent solution or HEPA-vacuum it while in the work area (or clean changing room). There are no special requirements for the disposal of moldy materials.
  7. Remove and dispose of porous materials, like drywall or carpet and padding that have been wet for longer than 48 hours.

    • Porous materials like drywall tend to remain wet, especially the bottom portion, even after the source of water is gone. If drywall has been wet for longer than 48 hours, remove the drywall approximately 3 feet up from the floor.
    • Isolate the room or rooms where the demolition is being performed with plastic, and use a fan to create negative pressure in the room.

  8. Remove disposable clothing before leaving isolated areas to prevent the tracking of mold-containing dusts outside of the work area.
  9. HEPA-vacuum and clean the work area and egress pathways (and clean changing room if present) prior to removing isolation barriers.
  10. Discard plastic sheeting after use.
  11. Leave all areas dry and visibly free from mold, dust, and debris.

HVAC Systems (Small isolated area of mold growth in the HVAC system (less than 10 square feet) - e.g. box filter

Mold growth in heating, ventilation, and air conditioning (HVAC) can affect the whole house. Consider hiring a professional to do this work.

  1. Only individuals trained on proper cleaning methods and personal and potential health hazards and the design and function of the HVAC system should conduct remediation.
  2. Respiratory protection (e.g. N-95 disposable respirator), in accordance with the OSHA respiratory protection standard (29 CFR 1910.134), is recommended. Gloves and eye protection should be worn.
  3. Shut down the HVAC system prior to any remedial activities.
  4. Avoid any work practice that creates excessive dust. Use of power tools is not recommended. Good practices include:
    • Cleaning or gently misting surfaces with a dilute soap or detergent solution prior to removal.
    • Using a high-efficiency particulate air (HEPA) vacuum attachment to collect dust If power tools are used.
    • Using a vacuum equipped with a HEPA filter at the point of dust generation.
  5. Consider the use of plastic sheeting to isolate other sections of the system.
  6. Clean materials that can be cleaned with a soap or detergent solution. (See mold cleaning page.)
  7. Remove, in sealed plastic bags, materials that cannot be cleaned (e.g. insulation of interior-lined ducts, flexible ducts, and filters). There are no special requirements for the disposal of moldy materials.
  8. HEPA-vacuum and clean (See mold cleaning page.) the work area and egress pathways prior to removing isolation barriers.
  9. Discard plastic sheeting after use.
  10. Leave all areas dry and visibly free from mold, dust, and debris.
  11. Check that other quality assurance indicators have also been met.

Mold Cleanup Quality Assurance

Measures to ensure the quality and effectiveness of remediation should be taken regardless of the project size. Evaluations both during and after remediation should be conducted to confirm the effectiveness of remedial work, particularly for large-scale remediation. At a minimum, these quality assurance indicators should be followed and documented:

  • Identifying and eliminating the underlying moisture problem.
  • Ensuring that isolation of the work area is appropriate and effective.
  • Performing mold removal and worksite cleanup according to the site-specific plan.
  • Properly addressing any additional moisture or mold damage discovered during remediation.
  • Upon completion of remediation, ensuring that surfaces are free from visible dust and debris.
  • If environmental sampling was performed, ensuring that the results of such sampling were evaluated by a trained building or environmental health professional.

For more information, see the Environmental Protection Agency (EPA) document "Mold Remediation in Schools and Commercial Buildings."

 Related Links


Contacts

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