§ 1-43 Post-Abatement Clearance Air Monitoring.
RCNY § 1-43
Post-abatement clearance air monitoring requirements are as follows: (a) (1) Sampling shall not begin until a visual inspection, conducted by a project monitor who is independent of the abatement contractor and by the asbestos handler supervisor, confirms that all containerized waste has been removed from work and holding areas and there is no visible ACM debris or residue on or about all abated surfaces; and (2) Sampling shall not begin until at least 1 hour after the area is dry from the third cleaning (see 15 RCNY § 1-112(h)) and no visible pools of water or condensation remain. For pre-demolition asbestos abatement activity, sampling shall begin 2 hours after the area is dry and no visible pools of water or condensation remain.
(b)Samplers shall be placed at random around the work area. If the work area contains the number of rooms equivalent to the number of required samples based on floor area, a sampler shall be placed in each room. When the number of rooms is greater than the required number of samples a representative sample of rooms shall be selected.
(c)The samplers must be placed separate and apart from one another in locations outside the work area but within the building and shall be located to capture any air that might escape through the isolation barriers and shall be no further than 50 feet from the entrance to the work area, and 25 feet from the isolation barriers.
(d)The following aggressive sampling procedures shall be used within the work area during all clearance air monitoring: (1) Before starting the sampling pumps, use forced air equipment (such as a 1 horsepower leaf blower) to direct exhaust air against all walls, ceilings, floors, ledges and other surfaces in the work area.
(i)For asbestos projects: this pre-sampling procedure shall take at least 5 minutes per 1,000 sq. ft. of floor area; then install one 20-inch fan per 10,000 cubic feet of room space. Then immediately place the fan on slow speed and point it toward the ceiling.
(ii)For pre-demolition asbestos abatement activity, this pre-sampling procedure shall take at least three minutes, after which the 20-inch fan shall be left running unattended in the work area throughout sampling. This procedure shall be acceptable when the floor area of the work area is less than 500 square feet. At or above 500 square feet of floor area within the work area, the aggressive sampling procedures specified in this subdivision (d) for asbestos projects shall be conducted.
(2)Start the sampling pumps and sample for the required time or volume.
(3)Turn off the pump and then the fan(s) when sampling is completed.
(e)For post-abatement monitoring, area samples shall conform to the following schedule: Area Samples for Analysis byMinimum Volume Flow Rate PCM 1,800 Liters 5 to 15 liters/min. TEM 1,250 Liters 1 to 10 liters/min.
(f)Each homogeneous work area which does not meet the clearance criteria shall be thoroughly recleaned using wet methods, with the negative pressure ventilation system in operation. New samples shall be collected in the work area as described above. The process shall be repeated until the work site passes the test.
(g)For an asbestos project with more than one homogenous work area, the release criterion shall be applied independently to each work area. (Amended City Record 4/28/2022, eff. 5/28/2022)
