Preparing the Work Area

Transcription

1 Preparing the Work Area

2 Work Area Preparation Objectives of Work Area Prep Sequence and Methods for Prep Engineering Controls: Negative Pressure Requirements, Equipment and Set-up

3 Purpose of Area Prep To protect the people outside the work area from asbestos exposure To protect the building surfaces and fixtures from asbestos contamination and water damage To confine the airborne asbestos within the work area

4 Work Area Prep Improper prepping will result in Damage to surfaces; wall, floors, fixtures etc. Additional expense and work to the contractor Delays that will affect the entire job timeline Possibly contaminating the area outside of the work area

5 Work Area Prep Guidance for prepping Specifications Specs are not a guideline they are part of a contract. They have to be followed Consultant May make recommendations to assist in meeting the specs Regulations Federal, State and City regulations have particular sections that affect work area prep More experienced persons An experienced Supervisor makes prep work go much easier

6 Materials Polyethylene (poly) 6 mil (Fire retardant for NYSDOL) Duct tape Spray adhesive Furring strips or wood blocks Tools OSHA DANGER SIGNS

7 Prep Materials The Basics: 6 mil poly Duct tape, heavy duty, 4-6 wide Spray glue OSHA required danger signs

8 Prep Materials Reinforced 10 mil poly for high durability

9 WORK AREA PREPARATION STEPS The following is a guideline listing the order of the required components of work area preparation. The regulation requirements may only be modified after filing for and receiving a variance for each change. NYCDEP and NYSDOL require that the worker Decon unit be constructed first and have it fully functional prior to preparing the work area.

10 WORK AREA PREPARATION STEPS 1.- Notice Of Asbestos Abatement Sign (Building Occupant Notice) 2.- Vacate Work Area and Restrict Entry 3.- Post Warning Signs 4.- Build Worker and Waste Decons 5.- Shutdown and lock out of electric power 6.- Shut Down the Heating, Ventilation, and Air- Conditioning System (HVAC)

11 WORK AREA PREPARATION STEPS 7.- Moveable and Fixed Objects 8.- Pre-Cleaning the Work Area 9.- Critical Barriers and Isolation Barriers 10.- Engineering Controls - Setting up the Negative Air System 11.- Elevator Shutdown or Isolation 12.- Plasticizing Floors, Walls & Ceilings of the Work Area

12 Notice Of Asbestos Abatement Sign (Building Occupant Notice) The Notice of Asbestos Abatement sign must be posted 10 calendar days prior to commencement of work on any asbestos project in NYS and 7 days in NYC. According to the state regulations, this sign must be posted on the floor or floors where the actual project is to be conducted.

13 Vacate Work Area and Restrict Entry Occupants and non-certified personnel must be removed from the work area before any work area preparation activities can take place and shall remain vacated until satisfactory clearance air sampling

14 Post Warning Signs Asbestos warning signs, required as per current OSHA regulations shall be posted to restrict access to the regulated abatement work area. During abatement activities, signs are posted at locations such that persons may take the necessary protective measures to avoid potential exposure.

15 Warning Signs Danger signs are to be placed at all entrances and exits to and from the work area It is an OSHA requirement that signs are to be in the language that workers and building occupants can comprehend.

16 Warning Signs

17 Warning Signs

18 Protecting The Public Poly and wood structures are erected to prevent the movement of people and contaminated air

19 Protecting The Public Lockable physical barriers in public areas are a must Asbestos danger sign on door to actual work area not the exterior door

20 Build Worker and Waste Decons The worker (personal) decon must be installed or constructed prior to preparatory activity in the work area or before disturbing ACM. The waste decon must be installed or constructed before beginning abatement activities

21 Electricity Preparation Shutdown and lock out of all existing power to fixtures, lights, machinery and outlets within the enclosure. The asbestos abatement contractor shall provide temporary power and lighting to the regulated abatement work area, This temporary power shall be protected by a ground fault circuit interrupter (GFCI)

22 Temporary Electrical Power All circuits must be GFCI protected

23 Shut Down the Heating, Ventilation, and Air-Conditioning System (HVAC) The HVAC system which services the proposed work area must be shut down or isolated to prevent asbestos fibers from escaping into other areas of the building. All vents and air ducts within the work area must be covered and sealed with two layers of 6-mil polyethylene and duct tape. These "isolation barriers" must remain in place until final air clearance testing.

24 Moveable and Fixed Objects Moveable objects such as furniture, pictures and other items have to be removed from the work area prior to abatement. Fixed objects and other items which are to remain within the regulated abatement work area shall be pre-cleaned using HEPA-filtered vacuum equipment and/or wet cleaning methods. Such objects and items shall be covered with two layers of at least 6-mil fire retardant plastic sheeting and sealed airtight with duct tape.

25 Furniture & Equipment

26 Furniture & Equipment These types of items may not always be contaminated but if they are they need to be cleaned with HEPA vacuum before moving and storage

27 Pre-Cleaning the Work Area The regulated abatement Work Area are cleaned using HEPA filtered vacuum equipment or wet cleaning methods or both. Methods that raise dust, such as sweeping or vacuuming with non HEPAfiltered equipment shall be prohibited. ACM/PACM shall not be disturbed during pre-cleaning.

28 HEPA Vacuum Wet Wipe

29 Critical Barriers and Isolation Barriers Isolation Barriers as per ICR 56 are temporary hard-wall barriers to complete the containment enclosure and establish the asbestos project regulated abatement Work Area. Constructed of conventional 2 x 3 (minimum) stud framing, 16 on center maximum, plywood or oriented strand board (OSB) sheathing material of at least 3/8 inch (NYS) or ½ inch (NYC) thickness shall be fastened to the work area side of the barrier partition.

30 Isolation Barriers Isolation Barrier Cont d: Sealing of Isolation Barriers: The edges of the isolation barrier partition shall be sealed at the floor, ceiling, walls and fixtures using caulk or fireretardant expandable foam to form an airtight seal. Plasticizing Isolation Barriers. The regulated abatement work area side of the isolation barrier partition shall be covered with two (2) layers of, at least, six (6) mil fire-retardant plastic sheeting with staggered joints and sealed airtight.

31 Critical Barriers The construction of critical barriers to seal off all openings and penetrations to the regulated abatement work area including, but not limited to operable windows, skylights, doorways, ducts, corridors (which shall not be used for passage), HVAC system, diffusers, grills, seams and any other penetrations to surfaces within the work area.

32 Critical Barriers Critical barriers are constructed using two independent layers of at least 6-mil fire-retardant plastic sheeting with each layer sealed separately with duct tape. Caulk and fire-retardant expandable foam may be used to seal small openings or penetrations.

33 Critical Barriers and Isolation Barriers Critical Barriers and Isolation Barriers When properly placed will make a room airtight. All critical barriers and isolation barriers must be left in place until the completion of the project.

34 Critical Barriers

35 Critical Barriers

36 Critical Barriers

37 Engineering Controls The main function of an asbestos professional is to abate the asbestos in such a manner as to prevent fibers from becoming airborne. To achieve this, a variety of engineering controls are used to help reduce the amount of fibers generated in the asbestos abatement process.

38 Engineering Controls The engineering controls help a contractor to perform the job more effectively and reduce the hazard in the work area. Wetting the Asbestos: The EPA, OSHA, NYS and NYC all law require that asbestos be adequately wetted and sufficient time be allowed for penetration to occur prior to abatement.

39 Engineering Controls To wet the asbestos, a contractor will use Amended Water. Amended water is water that has a surfactant added to it. Amended water makes wetting and penetrating the asbestos containing material more effective.

40 Engineering Controls Negative Air Filtration: The use of Negative Air Filtration in conjunction with the other engineering controls will remove asbestos fibers from the abatement area.

41 AIR FILTRATION DEVICES One of the most important pieces of equipment used in the asbestos removal process is the negative air ventilation unit. These units are known by several different names including Micro-Trap, Red Barron, Hog, negative air machine (NAM), negative air pressure unit (NAPU), negative air unit (NAU), and air filtration device (AFD).

42 AIR FILTRATION DEVICES Both City and State regulations require the negative air ventilation units become operational after critical barriers and isolation barriers are installed.

43 Negative Air Machines (NAM) Provide ventilation in the work area by drawing air from outside Help prevent fibers from escaping by lowering the pressure inside the work area (Creates Negative Pressure) Continually filters fibers out of the air

44 Types Of Negative Air Machines Machines are rated by how much air is drawn through the unit in a minute-cfm 2,000 CFM typical rating HEPA vacuums 85 to 200 CFM

45 Negative Air Machines Typical 2000 CFM machine 4000 CFM unit

46 Negative Air Machines There are 3 filters: ½ pre-filter (coarse) 2 secondary filter (fine) ~12 HEPA filter If the coarse pre-filter and fine secondary filter are changed often the HEPA lasts longer before becoming clogged with dust The HEPA filter is typically rated in running hours

47 Negative Air Machines OSHA, NYSDOL & NYCDEP require a minimum of 4 air changes per hour. NAM s are exhausted to the outside of the building This will require windows or other openings that can be sealed

48 NAM Exhaust Plywood and aluminum duct stock make a good template in the window frame (or other openings, HVAC opening etc.) If in an office-type building, the windows are often permanently mounted and may have to be removed by a specialty contractor.

49 Negative Air Machines

50 Negative Air Machines

51 Negative Air Machines

52 Negative Air Machines NAM exhaust NAM s

53 Negative Pressure OSHA, NYSDOL & NYCDEP regulations require a minimum negative pressure of column inches of water Proof of maintaining negative pressure as evidenced by manometric measurements (negative pressure recorder)

54 Negative Pressure Recorder

55 Negative Pressure Recorder The plastic tube is inserted through the poly; the device measures the pressure differential between the work area and the area outside of the work area

56 Negative Pressure Recorder Many of these devices have strip chart capabilities that can print out readings at desired time intervals; hourly, daily etc. NYSDOL requires a recording device for proving that negative pressure is properly maintained to other employers and the public.

57 Negative Pressure

58 Negative Pressure Constructing an airtight work area in conjunction with operating the negative air machines creates a negative pressure environment. If the work area were totally airtight, a vacuum would be created. However an abatement area has openings, which allow outside air to rush into the work area because of the draw from the negative air unit.

59 Negative Pressure The negative pressure environment has to be maintained to such a degree that should there be a rip or tear (breech) in the barriers, outside air would rush into the work area. This keeps the asbestos fibers inside the work area and protects building occupants

60 Negative Pressure Since the work area should be airtight, air is only allowed to enter the work area through the Decons and makeup air vents. Air flows through from the openings and then to the negative air units in the work area. The units should be strategically placed throughout the work area as far from the Decons as possible. This allows the air to pass through every part of the work area

61 Negative Air Machines Decon Make up Air Load Out Neg Air Machines NAM s should be placed in a variety of locations in the work area so that the air moves through the area providing proper ventilation and helps keep fibers levels controlled

62 Negative Pressure Once abatement has begun, the units must run continuously to maintain negative pressure until the job is completed, 24 hours a day, seven days a week. Since airborne asbestos fibers are microscopic in size and tend to remain in suspension for a long time, the negative air units must be kept operational throughout the entire abatement, cleaning and final clearance processes.

63 Negative Pressure Continuous operation of the units during the final clean-up and clearance process allows the units to remove the suspended asbestos fibers from the air. This is very important to a contractor who must rely on air sampling results to determine if the fiber concentration is in compliance for reoccupancy. In addition, continuous operation of the units will ensure that there is no leakage of contaminated air outside the enclosure should the fiber levels be unusually high.

64 Plasticing the Work Area

65 Preparation of the Work Area The proper preparation of the work area prior to asbestos abatement is key to keeping these fibers contained in a specific space. Some jobs will require far more preparation detail than others.

66 Plasticizing Floors, Walls & Ceilings of the Work Area NYSDOL: All floor, wall and ceiling surfaces shall be covered with two layers of, at minimum, 6-mil fire-retardant plastic sheeting. Plastic sheeting is not required to be placed on any surface where abatement of ACM will be performed.

67 Plasticizing Floors, Walls & Ceilings of the Work Area The DEP requires the poly be placed on the floor and walls only. The other requirements are similar to the State except that the floor poly extends up the wall 6 inches in NYC. Also, NYCDEP requires seams between adjacent layers be a distance of at least 6 inches

68 Plasticizing Floors, Walls & Ceilings of the Work Area The floor shall be plasticized first, and its plastic sheeting shall extend up the walls a distance of at least twelve (12) inches on all sides. The walls shall then be plasticized by applying plastic sheeting from the ceiling to the floor, overlapping the floor sheeting by at least 12 inches. The ceiling shall then be plasticized, overlapping the walls by at least 12 inches, to form a secure airtight seam.

69 Plasticizing Floors, Walls & Ceilings of the Work Area This process shall be repeated for the second layer of plastic sheeting for the floor, walls and ceiling. All seams within a layer shall be separated by a distance of at least six feet and sealed airtight with duct tape. All seams between layers shall be staggered at least two feet.

70 Wall & Floor Poly Wall Poly Floor

71 Wall Poly Prep is below trim to minimize damage Cardboard pieces help hold up poly

72 Floor Prep

73 Floor Prep

74 Finished Prep

75 Finished Prep

76 Emergency Exit Work area must have at least one emergency exit

77 REMOVAL

78 REMOVAL EPA, OSHA, New York State and New York City require that any asbestos removed must be kept wet during the removal and when it is bagged. Two advantages to the use of wet methods for removing asbestos materials include a reduction in airborne fiber concentrations, which are generated during removal, and a reduction in the effort required removing the material.

79 REMOVAL Wet removal is based on the ability of water to lower the potential for the asbestos-containing material to release airborne asbestos fibers and increase the settling rate of fibers that are released. Airborne fiber concentrations may be reduced significantly by using wet removal techniques rather than dry.

80 REMOVAL At this point of the abatement project, the work area has been sealed off with at least two layers of 6-mil polyethylene on the floors and two layers of 6-mil polyethylene on the walls. The decontamination unit and negative air filtration units are in place, and the scaffolding, ladders, various sizes of shortand long-handled scrapers and other removal equipment have been brought into the work area.

81 REMOVAL The first step in the removal process is to thoroughly wet the ACM with a lowpressure mist of amended water. Then the material will be continuously wetted while being removed.

82 REMOVAL Gross removal: Is when most of the material is abated. Some of the workers will use scrappers to remove the material, while others will be involved with keeping the material wet and packaging the debris into the appropriate container.

83 REMOVAL ACM, on detachment from the substrate, shall be directly bagged or dropped into a flexible catch basin and subsequently bagged or containerized. (Title 15, Chapter 1 uses the word promptly ). According to ICR-56, cleanup of accumulations of loose debris/waste material shall be performed whenever enough loose debris/waste material has been removed to fill a single leaktight container.

84 CLEANING PROCESS Once all the ACM has been removed and no gross debris is observed, the cleaning process starts. Typically a combination of brushing and wet wiping is used to remove the remaining residue. Wet rags and High efficiency particulate air (HEPA) vacuum cleaners are also useful for removing "hard-to-get-to" residue.

85 FINAL CLEANING Any cleaning of the work area is to be accomplished by wet wiping and/or HEPA filtered vacuuming. The contractor will choose the appropriate method based on the surface to be cleaned.

86 FINAL CLEANING All surfaces inside the Work Area are included in the cleaning, including the Decon(s), floors, walls, and the surfaces where asbestos has been abated.

87 DAILY CLEANING NYC VS NYS NYCDEP Title 15, Chapter 1 The following requirements shall be followed on all large asbestos projects: 1. Visible accumulation of waste must be bagged whenever there is enough to fill a bag or at the end of each shift whichever shall occur first. 2. Non-metal shovels and/or HEPA vacuums (i.e. dust pans, squeegees etc.) allowed. 3. Accumulations of dust cleaned daily. 4. Waste decon shall be cleaned twice after the removal of waste. When worker decon is used for waste, shower shall be cleaned with a detergent prior to wet-cleaning of decon. 5. Worker decon cleaned, as appropriate, after each shift change and meal break. 6. Excessive water accumulation or flooding shall require work to stop until water is collected. NYSDOL Code Rule-56 The following requirements will be required on all large and small projects: 1. Cleanup of accumulations of loose debris/waste material shall be performed whenever there is enough to fill a single leak-tight container appropriate for the type of ACM being removed. Cleanup of all remaining waste shall be performed at least once prior to close of each workshift. 2. Non-metal shovels allowed. 3. Accumulations of dust or debris shall be cleaned off all surfaces on a daily basis using HEPA-vacuum or wet-cleaning methods or both. 4. Decontamination system enclosures shall be HEPA-vacuumed or wet-cleaned or both at the end of each workshift. 5. The regulated abatement work area, holding area, waste trailer and hardtop dumpster areas must be kept free of uncontainerized asbestos waste/debris at all times.

88 FINAL CLEANUP PROCEDURES NYC VS NYS NYCDEP Title 15, Chapter 1 1. First cleaning. All surfaces are HEPA vacuumed first and then wet cleaned. 2. Remove the cleaned layer of poly sheeting. Barriers and Decons remain in place. 3. Wait 12 hours. 4. Second Cleaning. All surfaces HEPA vacuumed and wet cleaned again. 5. Remove remaining layer of poly. Barriers and Decons remain in place. 6. Wait 4 hours. 7. Third Cleaning. Wet clean and/or HEPA vacuum all surfaces. All equipment (except NAU s) and tools shall be removed and properly decontaminated. 8. Conduct final visual inspection. 9. Encapsulate all abated surfaces. 10. Wait until at least 1 hour after the area is dry from the 3 rd cleaning and no visible pools of water or condensation remain. 11. Air filtration must be at least two air changes per hour at this point. 12. Begin aggressive/final clearance sampling. NYSDOL Code Rule First Cleaning. All surfaces are wet-cleaned using rags, mops and sponges. 2. Apply a thin coat of a lockdown encapsulant to all surfaces except abated surface or surfaces. 3. Conduct appropriate waiting/settling, or drying time (see table on next page). 4. Remove the cleaned, exposed top layer of plastic sheeting. Barriers and Decons remain in place. 5. Second Cleaning. All objects and surfaces cleaned using HEPA vacuums and then wet cleaned. 6. Conduct appropriate waiting/settling, or drying time Remove remaining bottom layer of poly. Barriers remain in place. 7. Third Cleaning. All objects and surfaces cleaned using HEPA vacuums and then wet cleaned. All equipment (except NAU s) and tools shall be removed and properly decontaminated. 8. Conduct appropriate waiting/settling, or drying time 9. Visual inspections conducted by both the asbestos abatement contractor s supervisor and a project monitor. 10. Maintain air filtration for at least four air changes per hour. 11. Begin aggressive/final clearance sampling.

89 VISUAL INSPECTION Prior to the final clearance sampling, a visual inspection will be performed by the third party consulting company. The project monitor visual inspection for completeness of abatement and completeness of cleanup shall be performed as per the provisions of the current ASTM International Standard E1368 Standard Practice for Visual Inspection of Asbestos Abatement Projects.

90 VISUAL INSPECTION The aggressive clearance sampling will start ONLY once the visual inspection is completed and it has been determined that the scope of abatement work for the asbestos project was accomplished, and no visible asbestos debris/residue, pools of liquid or condensation remain inside the work area.