Appendix B PROCEDURES FOR REMOVAL OF MOULD-CONTAMINATED MATERIALS

Transcription

1 Appendix B PROCEDURES FOR REMOVAL OF MOULD-CONTAMINATED MATERIALS The following procedures are presented as a guide. Comprehensive site-specific technical specifications for the removal of mould-contaminated material may be required for extensive removals. All remediation workers should understand the specifications before attempting to remove mould-contaminated material. In all situations, the underlying cause of water moisture/intrusion must be rectified or fungal growth will recur. Any initial water infiltration should be stopped and cleaned immediately. An immediate response (within 24 to 48 hours) and thorough clean up, drying, and/or removal of water damaged materials will prevent or limit mould growth. If the source of water is elevated humidity, relative humidity should be maintained at levels below 60% to inhibit mould growth. Emphasis should be on ensuring proper repairs of the building infrastructure, so that water damage and moisture buildup does not recur. The goal of remediation is to remove or clean contaminated materials in a way that prevents the emission of mould and dust contaminated with mould from leaving a work area and entering an occupied or non-remediated area, while protecting the health of workers performing the remediation. The remediation methods described below were designed to achieve this goal, however, due to the general nature of these methods, it is the responsibility of the people conducting remediation to ensure the methods enacted are adequate. The remediation methods outlined below are not meant to exclude other similarly effective methods. Any changes to the remediation methods outlined below, however, should be carefully considered prior to implementation. GENERAL GUIDELINES Notify affected building occupants of the mould remediation work plan (i.e. timeline, hours of work, precautions required). While removal of occupants from spaces adjacent to the remediation work area is not necessary in all circumstances it may be warranted in circumstances for person(s) recovering from surgery or are immunocompromised, children and the elderly. If feasible, perform remediation after normal working hours when the building is unoccupied. When performing remediation work (see following sections), shut down the heating, ventilating, and airconditioning (HVAC) system serving the floor or area where the remediation work is performed. Clean all moveable non-porous uncontaminated content items, first with a high efficiency particulate air (HEPA)-filtered vacuum cleaner, and then with a damp (not wet) cloth. Remove these items from the work area before starting the removal of mould-contaminated materials. Non-porous (e.g., metals, glass, and hard plastics) and semi-porous (e.g., wood, and concrete) materials that are structurally sound and are visibly mouldy can be cleaned and reused. Cleaning should be done using a mild detergent solution. If the area has been contaminated with unsanitary water (e.g. sewage) a disinfectant should be used. Porous materials such as ceiling tiles, insulation, and wallboards that have been affected by unsanitary water must be removed and discarded. Porous materials (e.g., fabrics) affected by clean water can be cleaned, can be reused, but should be discarded if possible. All materials to be reused should be dry and visibly free from mould. Except in cases of extensive microbial contamination (e.g., sewage backflow, as part of a remediation and clean-up process), do not apply disinfectant to mould-damaged materials. The use of biocides in this manner can pose health concerns for remediation workers as well as for people in adjacent occupied spaces. Furthermore, the use of biocides does not address the possible health concerns from the presence of remaining non-viable moulds. If disinfectants are applied in a liquid state (mixed with water), the

2 elevated moisture content that may be left as a residue in porous materials (after the disinfecting agent has dissipated) may subsequently cause new microbial growth. Avoid the use of unnecessary sealants, glues (except for affixing containment barriers to walls), solvents or other chemicals which may impact the health of building occupants. In the event that their use is required, advise onsite personnel, provide relevant material safety data sheets (MSDSs), and ensure that precautions are taken to minimize health risks to occupants. Limited use of water for cleaning of impacted surfaces is allowed. However surfaces to be cleaned should be damp-wiped and not soaked or sprayed. Stop all work if there is a break in containment barriers. When containment is required, re-seal plastic barriers prior to continuing with remediation work. Conduct evaluations during as well as after remediation to confirm the effectiveness of remedial work, particularly for large-scale remediation. Eating, drinking or smoking is not permitted in the area of mould remediation Dry sweeping is not permitted in the work area. Only vacuums fitted with effective HEPA (High Efficiency Particulate Arrestance (HEPA)-filter dust collection are permitted. MOULD REMEDIATION: PRECAUTIONS AND SAFE WORK PRACTICES Levels of safe work practices and precautions for mould remediation are primarily determined by the size of the area impacted by mould contamination. The extent of mould contamination area is usually based on a visual inspection. Air and surface sampling are not required to undertake remediation or determine the mould remediation level. Described below, based on the EACO Mould Abatement Guidelines Edition 3, are guidelines and procedures for three levels of mould remediation work. Level of Description Size of Mould Impacted Area Mould Remediation Level 1 Small Isolated Areas 1m 2 (10 sq. ft) or less of building materials or Clean-Up of <1m 2 (10ft 2 ) of mould growth in Heating, Ventilation and Air Conditioning Systems (HVAC) in Non-Occupied Areas Level 2 Medium Areas 1-10m 2 ( sq. ft.) or less than 1m 2 (<10ft 2 ) in Heating, Ventilation Level 3 Large Areas or More Than 1m 2 in HVAC systems and Air Conditioning Systems (HVAC) in Occupied Areas Greater than 10m 2 (>100 ft 2 ) or Greater than 1m 2 (>10 ft 2 ) in HVAC systems

3 Mould Remediation Guidelines: Precautions and Safe Work Practices LEVEL 1 Small Isolated Areas: Less than 1m 2 (or <10 sq. ft) of Building Materials or Clean Up of Less than 1m2 (10ft2) of Mould Growth in HVAC Systems in Non-Occupied Areas, such as Mechanical Rooms Work Area Occupancy Worker Qualifications Personal Protective Equipment Safe Work Practices for Mould Remediation Work area should be unoccupied. Vacating people from spaces adjacent to the work area is not necessary but is recommended in the presence of infants (less than 12 months old), persons having undergone recent surgery, immune suppressed people, or people with chronic inflammatory lung diseases (e.g., asthma, hypersensitivity pneumonitis, and severe allergies). May be conducted by regular building maintenance staff who are trained on proper clean-up methods, personal protection, and potential health hazards related to mould exposure and mould abatement. Mould abatement workers must be fit to work with potential mould exposure. Required: An Air Purifying Filtering N95 Single Use NIOSH Approved Respirator or better Gloves Eye Protection Full-body dust impervious Hooded Coveralls, securing at ankles and wrists HVAC System: Required Turn off the HVAC systems and seal over any diffusers/ducts serving the work area, Dust Suppression Light misting of surface with dilute soap/detergent solution prior to disturbance of mouldy materials Use of HEPA vacuum or tools fitted with HEPA filter to clean all tools, supplies & equipment in the work arearequired Floor Covering: Required Place a plastic drop sheet on the floor of the work area and seal with tape Decontamination Facility: Not Required Personal Hand Hygiene: Required Enclosure: Not required Signage: Not required Contaminated Materials Remove any porous materials to a point beyond the immediate area of visible contamination for a distance of 30 cm in all directions Waste Disposal: Double Bag all mould contaminated materials including but not limited to building debris, disposable PPE, plastic sheeting and label bag; No special environmental hazardous waste disposal requirements Quality Assurance Visual Inspection: Required Verify area and materials are dry and free of contamination and debris Air Monitoring: Not required but may be considered for sensitive areas If cleaning involves use of a detergent solution or disinfectant in case where work area has been contaminated as a result of sewage spill, back up, product MSDSs must be reviewed for appropriate hand, eye and respiratory protective equipment.

4 Level 2 Work Area Occupancy Worker Qualifications Personal Equipment Protective Safe Work Practices for Mould Remediation Quality Assurance Medium Areas: 1-10m 2 (10-100ft 2 ) or less than 1m 2 (<10ft 2 ) in Heating, Ventilation and Air Conditioning Systems (HVAC) in Occupied Areas Work area to be unoccupied and secured; Access to be restricted to authorized personnel only Vacating people from spaces adjacent to the work area is not necessary but is recommended in the presence of infants (less than 12 months old), persons having undergone recent surgery, immune suppressed people, or people with chronic inflammatory lung diseases (e.g., asthma, hypersensitivity pneumonitis, and severe allergies). Workers trained and equipped in mould remediation strategies and who are fit to work with potential mould exposure. Health & Safety Professional with mould related experience should be consulted prior to the remediation work to provide oversight during the remediation work for quality assurance by means of inspection of work area, enclosures, barriers, air monitoring during, possibly and post abatement and compliance with the work plan. A competent supervisor must be present during all contaminated work. Required: NIOSH Approved Air Purifying Half Face Re-Usable Respirator fitted with 100 series particulate filter Gloves, Safety Glasses appropriate for the work being done Full-body dust impervious Hooded Coveralls-securing at ankles & wrist Disposable Boot covers or separate work boots that can be HEPA vacuumed or wet wiped prior to removal from work area HVAC System: Required Floor Covering: Required Turn off the HVAC systems where Place a plastic drop sheet on the possible and seal over any supply and floor of the work area and seal with return air openings immediately tape adjacent to the work area Signage: Required "Caution Mould Abatement: Wear Assigned Protective Equipment" Authorized Personnel Only Dust Suppression: Light misting of surface with dilute soap/detergent solution prior to disturbance of mouldy materials Use of HEPA vacuum or tools fitted with HEPA filter-required Decontamination Facility: Recommended Personal Hand Hygiene: Required Before exiting work area-all footwear, coveralls and PPE shall be cleaned via wet wiping or HEPA vacuum Visual Inspection: Required Verify area and materials are dry and free of contamination Enclosure: Required Isolate Work Area completely using plastic sheeting sealed with tape Provide and maintain enclosure under Continuous Negative Pressure via HEPA filtered exhaust fan, discharging to outside whenever possible Double Flap Entrance to Enclosed Work area Inspect Enclosure at beginning and end of work shift Contaminated Materials Remove any porous materials to a point beyond the immediate area of visible contamination for a distance of 30 cm in all directions Waste Disposal: Double Bag all mould contaminated materials and label bag; No special environmental hazardous waste disposal requirements Air Monitoring: During Abatement: Recommended; Post Abatement: Required

5 Level 3 Work Area Occupancy Large Areas greater than 10m 2 (>100 ft 2 ) or more than 1m 2 (10ft 2 ) in HVAC Systems Work area to be unoccupied and secured; Access to be restricted to authorized personnel only Vacating people from spaces adjacent to the work area is recommended in in the presence of infants (less than 12 months old), persons having undergone recent surgery, immune suppressed people, or people with chronic inflammatory lung diseases (e.g., asthma, hypersensitivity pneumonitis, and severe allergies). Worker Qualifications Health & Safety Professional with specialized knowledge and experience performing mould investigations is to be consulted for a site specific work plan, overseeing the remediation work for quality assurance by means of inspection of work area, enclosures, barriers, air monitoring during, possibly and post abatement and compliance with the work plan. A competent supervisor must be present during all contaminated work. Workers trained and equipped in mould remediation strategies and who are fit to work with potential mould exposure Personal Equipment Protective Safe Work Practices for Mould Remediation Required: NIOSH Approved Air Purifying Full Face Re-Usable Respirator fitted with 100 series particulate filter or Powered Air Purifying Respirator (PAPR) equipped with HEPA Gloves &Safety Glasses appropriate for the work being done Full-body dust impervious Hooded Coveralls-securing at ankles & wrist Disposable Boot covers or separate work boots that can be HEPA vacuumed or wet wiped prior to removal from work area HVAC System: Required Turn off the HVAC systems and seal over any supply and return openings in the work area and immediately adjacent to the work area. Floor Covering: Required Place a plastic drop sheet on the floor of the work area and seal with tape Enclosure: Required Isolate Work Area completely using plastic sheeting sealed with tape Provide and maintain enclosure under Continuous Negative Pressure via HEPA filtered exhaust fan, discharging to outside whenever possible; Negative Pressure within the enclosure to be continuously measured Double Flap Entrance to Enclosed Work area Inspect Enclosure at beginning and end of work shift

6 Signage: Required "Caution Mould Abatement: Wear Assigned Protective Equipment" Authorized Personnel Only Decontamination Area: Required Area with airlock entry to work area consisting of two chambers: clean room and dirty room, with triple flap doorway curtains Clean change room shall be equipped with at a minimum a wash basin, fresh water, soap, towels and clean coveralls. Exit the Contaminated work area into the dirty room where PPE will be HEPA vacuumed to remove gross debris. Dust Suppression: Light misting of surface with dilute soap/detergent solution prior to removal Use of HEPA vacuum or tools fitted with HEPA filter: Required Personal Hand Hygiene: Required Before exiting work area-all footwear, coveralls and PPE shall be cleaned via wet wiping or HEPA vacuum; all disposable materials discarded in double bag Contaminated Materials Remove any porous materials to a point beyond the immediate area of visible contamination for a distance of 30 cm in all directions Waste Disposal: Double Bag all mould contaminated materials within the contaminated area and label bag; No special environmental hazardous waste disposal requirements Quality Assurance- Where possible, a separate waste transfer room should be available for the double bagging and HEPA vacuuming of debris before transfer. Visual Inspection: Required Contained area and decontamination room must be HEPA vacuumed and cleaned with a damp cloth and/or mop and a detergent solution prior to the removal of isolation barriers All areas must be left dry and visibly free from contamination and debris Air Monitoring: During Abatement: Required Post Abatement: Required Must be conducted prior to re-occupancy with the HVAC system in operation to determine if the area(s) served by the system are fit to reoccupy. "Air samples collected in the work area will to be compared with samples taken in adjacent areas from the work area or outdoors". Surface samples may also be collected in the work area to verify absence of mould growth. Following confirmation of acceptable conditions, containment barriers can be removed upon consent from consultant.