MINIMUM NUMBER AND LOCATION OF SINGLE-SURFACE DUST SAMPLES
Clearance Category | Category Description | Number and location of Single-Surface Wipe Samples in Each Area1 | Number and Location of Composite Wipe Samples |
1 | Interior treatments No containment within dwelling | Two dust samples from at least four rooms in dwelling (treated or untreated): * One interior window sill or window trough, alternating between rooms. * One floor. AND * For common areas, one for every 2,000 ft 5 of a common area room floor (if present) | Three composite samples for every batch of four rooms (whether treated or untreated): * One floor composite. * One interior window sill composite * One window trough composite. AND * For common areas, one floor subsample for every 2,000 ft 5 (if present); up to 8,000 ft 5 can be sampled for every composite. |
2 | Interior treatments With containment (Plastic sheeting as airlock on doors between treated and untreated areas) | Same as Category 1 but only in every treated room (up to four rooms) AND One floor sample outside the containment area but within 10 feet of the airlock to determine the effectiveness of the containment system. This extra single-surface sample is recommended in 20 percent of the treated dwellings in multifamily housing and all single-family homes. * For common areas, one floor sample for every 2,000 ft 5 and one floor sample outside containment. | Same as Category 1 but only in every treated room AND One floor sample outside the containment area but within 10 feet of the airlock to determine the effectiveness of the containment system. This extra single-surface sample is recommended in 20 percent of the treated dwellings in multifamily housing and all single-family homes. * For common areas, one floor subsample for every 2,000 ft 5 (up to 8,000 ft 5 for each composite) and one floor sample outside containment. |
3 | Exterior treatments | Two dust samples as follows: * At least one dust sample on a horizontal surface in part of the outdoor living area (e.g., a porch floor or entry way). * One window trough sample on each floor where exterior work was performed. An additional trough sample should be collected from a few lower floors to determine if troughs below the area were contaminated by the work above. | Two dust samples as follows: * One composite on a horizontal surface in part of the outdoor living area (e.g., a porch floor or entry way). * One window trough composite for every four floors where exterior work was performed, including lower floors where exterior work was not done, if present. |
4 | Routine maintenance work | At least 1 floor dust sample for every 20 high-hazard jobs near the work area. | Same as single-surface sampling. |
5 | Soil treatment | One dust sample from the entryway. | One dust sample from the entryway. |
1.A room includes a hallway or a stairway If no window, just one floor sample must be collected When a closet is treated, the room to which it is attached should be tested A closet is not considered to be a separate room If all rooms received similar treatments and cleaning, only four rooms need to be sampled for clearance purposes More rooms may need to be sampled m larger dwellings The room to be sampled should be selected based on where most of the dust-generating work was done or m the judgment of the clearance examiner
W. Va. Code R. agency 64, tit. 64, ser. 64-45, tbl. 64-45 D