Microbial Remediation Services
Work Area Containment
These are based on various guidelines that are available in the industry and do not necessarily apply your project. These are for guideline purposes only and may or may not apply to your project.
Containment Purpose – Enclosure to prevent exposure to workers and occupants and to minimize the spread of contamination.
Full Negative Pressure Enclosure
Definition – The process of pumping filtered air out of the work area to create a lower pressure inside the work area as compared to outside.
Isolate each work area using barrier tape, polyethylene sheeting and plywood, sealing foam and warning signs.
The HVAC system serving each work area shall be shut down prior to beginning any remediation work.
Install critical barriers consisting of one (1) layer of 6 millimeter fire retardant Polyethylene sheeting:
• Entrances and openings to each designated work area
• Includes HVAC ducts
• Doors to remain closed
• Exposed duct work/seams
• Cover furnaces/heating systems, pipe penetrations
• Perform content preservation, cleaning and packing
• Perform pre-cleaning of surfaces in work area as necessary
• De-energize electrical service, if necessary, following lock out, tag out procedures
• Use ground fault circuit interrupts (GFCI) on all electrical cords and equipment
• Fire extinguishers inside and outside of work area
• Install temporary lighting (as needed)
• It may be necessary to provide alternate heating devices in the work areas during winter months
Construct Negative Pressure Enclosure:
• Install 6 millimeter Polyethylene sheeting (number of layers depends on the situation)
• Secure with duct tape (or wood supports as necessary)
• Cover all surfaces (except areas to be remediated)
• Overlap seams on Polyethylene sheeting
• Install HEPA filtered exhaust units
• Filter sizes 10 urn, 5 ura, 0.3 urn (this combination of filters will trap most spore sizes)
• There should be enough units to provide four (4) air changes per hour
• AFD Exhaust units should be exhausted to the exterior when possible
• Negative air pressure airflow can be checked using smoke tubes
Install a decontamination system:
The decontamination system should contain three (3) chambers with an air lock between each:
* Equipment room
• Shower room
• Clean room
Clean Up and Disposal Procedures
All cleanup activities will be performed under full containment of the work area. Personnel protective equipment will include a respirator with HEPA air filter, disposable suit, gloves and goggles.
Moldy materials including:
• Non-porous surfaces.
• Porous surfaces.
• Clothing, drapes, bedding, upholstered furniture, carpet and padding, wallboard, wood surfaces, books and papers.
Non-porous hard surfaces (i.e. glazed tile, plastics, metals, etc.):
• Wet wipe with mild detergent and water usually removes mold.
• HEPA vacuuming may be appropriate for heavy dust/dirt on surfaces.
• Wooden studs can be HEPA vacuumed to remove buildup of dust and spores, if necessary.
• Wet cleaning with a mild detergent and water with a nylon bristle brush.
• Do NOT saturate the wood.
• If the wood is structurally damaged, it must be replaced.
• Be certain wood is completely dry before enclosing or painting.
Concrete and cinderblock:
• Use HEPA vacuum to remove dust and spores if necessary.
• Clean surfaces with mild detergent and water.
• Do NOT saturate surfaces with water.
• Do NOT pressure wash interior surfaces
• Be sure concrete or cinderblock is allowed to dry completely.
• Evaluate quantity of mold and where it is present.
• Determine how mold occurred and where water or moisture came from.
• Small areas of mold on the surface of the wallboard can be cleaned.
• Large areas ofmold should prompt replacement of affected wallboard panels.
• Replacement of gypsum wallboard is often cheaper than cleaning, prepping and painting existing wallboard.
• The mold on the hidden side of the sheetrock is usually more than what is visible.
• Wet/moldy insulation should be removed from wall cavity.
• Remove visible mold with HEPA vacuum before removing wallboard.
Carpet and cushions:
• All carpet and padding should be dried.
• Mold growth on carpet:
• If less than ten (10) square feet of the carpet is affected by the mold, the carpet can be cleaned by steam cleaning and cleaning solution, allowed to dry and HEPA vacuumed.
• If more than ten (10) square feet of the carpet is affected by the mold, the caipet should be removed and discarded. Prior to removal, the carpet should be HEPA vacuumed.
• In areas where carpet is present in an area with moldy materials, but the caqjet is not moldy: HEPA vacuum the carpet and clean ifnecessary to remove musty odors.
Clothing, drapes, bedding and upholstered furniture:
• Active mold growth:
• Generally discard items; laundering or dry cleaning can be performed but staining and weakened fabric will likely occur where there was active mold growth.
• No mold growth:
• Launder, dry-clean or steam clean to remove most spores and musty odor.
Books and Papers:
• If wet and no mold – diy immediately or store in freezer or fieeze-dry.
• If wet and moldy – discard or dry and clean with HEPA vacuum.
• If dry and moldy – discard or clean with HEPA vacuum.
• Mild detergent solution and water.
• Clean furnishings such as tables and chairs as they are removed from the space.
• Place plastic bags or wrap items to be disposed of, such as moldy clothing etc. then remove from space.
• Clean visible mold from surfaces and bag or wrap in plastic.
• Cycle negative air machines or allow setting time of about 12 hours or more.
• Perform final cleaning from top down ofall surfaces.
• Currently there are no federal or state regulations governing mold waste disposal.
• EPA recommendations and good practices dictate that moldy materials be placed in plastic bags or wrapped in plastic and sealed.
• Waste should be sent to the landfill as construction and demolition (C&D) debris.