Section Env-A 1805.09 - Clearance Testing(a) At the completion of an asbestos abatement project but prior to dismantling the containment and decontamination system, the O/O shall obtain the services of an independent industrial hygienist to conduct clearance air sampling.(b) Prior to clearance sampling, the independent industrial hygienist shall conduct a thorough visual inspection of the work area for the presence of visible residue.(c) If visible residue is found by the independent industrial hygienist, the O/O shall continue cleaning the work area as specified in Env-A 1805.07(e).(d) After determining that no visible residue remains in the work area, the independent industrial hygienist shall take sufficient volumes of air for clearance sampling to accurately determine, to a 95 percent probability, fiber concentrations to 0.010 fibers/cubic centimeter (f/cc) of air.(e) Clearance air sampling shall be done no sooner than the earlier of 6 hours from the time the cleanup procedures of wet wiping and HEPA vacuuming are completed, or such time as all surfaces in the work area have dried. If all work area surfaces are dry at the completion of the cleanup procedures, no waiting period shall be required prior to beginning air sampling.(f) Aggressive sampling shall be used: (1) To ensure that any fibers deposited on surfaces within the work area are included in the sample; and(2) For all clearance sampling in schools and school buildings.(g) Except for schools and school buildings, non-aggressive sampling shall be used in areas where all uncontaminated wall, ceiling, and floor surfaces in the work area are not covered with sheeting.(h) The containment and worker decontamination system shall not be dismantled until clearance air sampling demonstrates the presence of no more than 0.010 fibers of length greater than 5 microns per cubic centimeter of air as determined by phase contrast optical microscopy, performed as described in "Asbestos and Other Fibers by PCM: Method 7400, Issue 2", National Institute of Occupational Safety and Health (NIOSH) Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94, available as noted in Appendix B.(i) The industrial hygienist shall provide copies of the clearance air sampling results to the department within 30 days of the date of clearance air sampling.N.H. Admin. Code § Env-A 1805.09
(See Revision Note at chapter heading for Env-A 1800) #9298, eff 10-21-08
Amended by Volume XXXVII Number 19, Filed May 11, 2017, Proposed by #12172, Effective 5/5/2017, Expires 5/5/2027.