(a) When visible emissions occur outside the work area, or any area air sample has indicated a determinant level of fiber concentrations greater than the larger of baseline levels or 0.01 f/cc, work shall stop for inspection.
(1) For large or small asbestos projects, the integrity of barriers, if disturbed, shall be restored. Clean-up of surfaces outside of the work area using HEPA vacuums or wet cleaning techniques shall be done prior to resuming abatement activities.
(2) For tent procedures, HVAC systems to or in the work area shall be shut down and the work area shall be wet cleaned or HEPA vacuumed until the area air samples indicate the fiber concentration is below the determinant level. If fiber concentrations remain above the determinant level for longer than 24 hours, isolation barriers and engineering controls shall be installed and maintained.
(b) Clearance and/or reoccupancy criteria. (1) The clearance criteria shall be applied to each homogeneous work area independently.
(2) For PCM analysis involved in alteration or renovation projects, the clearance air monitoring shall be considered satisfactory when every sample is less than or equal to 0.01 f/cc or less than the ambient concentration, whichever is larger.
(3) For TEM analysis, the clearance monitoring will be considered satisfactory if conducted in accordance with 40 C.F.R. Part 763, Subpart E, Appendix A Section IV – Mandatory Interpretation of Transmission Electron Microscopy Results to Determine Completion of Response Actions.
(4) Clearance air monitoring results shall be submitted directly to the Department within 24 hours of request.