(a) Areas that require sampling. - (i) Normal Access Areas and Low Access Areas shall be sampled or presumed to have target compound residue levels above the AL or AL-LAA, respectively.
- (ii) Non-accessible areas are not required to be sampled or remediated.
(b) Number of samples required in a Clanlab Assessment. - (i) The total area of the assessment shall be divided up according to zones based on mechanical ventilation systems if and where present. In each zone, the following minimum number of sampling locations is required. (Square footage (SF) refers to floor dimensions of the space). Samples may be from single locations or may be composite samples as described in section 6(e). Samples locations shall be chosen from randomly selected locations from different surfaces (e.g., floors, walls, ceilings, built-in components) and substrates (e.g., concrete, wood, drywall).
- (ii) Zones consisting of one or more identifiable room(s) on an air handling system.
| Area | Number of Samples |
| Up to 1000 SF | Thirty (30) locations |
| Each additional 1000 SF | Twenty (20) locations |
- (iii) Zones that contain one identifiable room within a contiguous area that has no air handling system.
| Area | Number of Samples |
| Up to 1000 SF in Normal Access Areas | Twenty (20) locations |
| Each additional 1000 SF in Normal Access Areas | Ten (10) locations |
| Low Access Areas | Five (5) locations per 2000 SF |
| Area | Number of Samples |
| Normal Access Areas adjacent to other assessed areas | Five (5) locations per 1000 SF |
- (iv) Zones that contain multiple identifiable rooms within a contiguoarea that has no air handling system.
| At least three (3) locations from each identifiable room shall be sampled |
| For the first 1000 SF, at least thirty (30) locations shall be sampled |
| For each additional 100 SF, three (3) locations shall be collected |
- (v) Data interpretation.
| Data from separate structures and separate zones of mechanical ventilation shall be interpreted separately |
| In large rooms where multiple samples are collected, a grid pattern may be used to determine the extent of migration of target compound |
(c) Sample Locations Selection. - (i) Structure Samples. Samples of the structure shall be collected from permanent (non-movable) non-porous and semi-porous surfaces in the quantity indicated under 6(b). The required number of samples shall be met not including any samples from locations on movable items (e.g., clothing or furniture) or on substrates that are known to have been installed since the person(s) who allegedly were involved in the Clanlab(s) accessed the structure.
- (ii) Sampling of movable items.
- (A) The structure and contents are presumed to have target compound residue levels above the AL prior to any testing performed. If the structure is tested and found be in compliance with the AL throughout the structure, movable items may be assumed to be in compliance. If the structure is in non-compliance throughout or in part, movable items may be assumed to be in non-compliance throughout, but may also be tested to determine whether they are in compliance. Movable items found outside the structure being assessed that are normally found or used inside structures shall be tested or assumed to be non-compliant.
- (B) If movable items are tested, composite or single surface samples shall be collected from non-porous and semi-porous items. Movable items shall be sampled at a minimum of fifty locations to assess the movable items in a structure. If all samples indicate compliance, then all movable items may be deemed compliant and do not require remediation. If some items are in compliance and some in non-compliance, only those items that were sampled and found to have target compound residue levels below the AL shall be deemed in compliance. Porous building materials shall be assumed to be non-compliant if the structure in which they are located is non-compliant. For example, attic insulation shall be assumed to be non-compliant if the attic framing or decking is non-compliant, and carpet shall be assumed to be non-compliant if nearby walls or other permanent items are non-compliant. Porous movable items shall be assumed to be non-compliant if non-porous and semi-porous items are found to be non-compliant or in absence of testing of non-porous and semi-porous movable items, if the structure is non-compliant.
(d) Sampling of HVAC systems. - (i) Samples shall be collected from at least one supply duct, one return duct (if present) and in the furnace (if present) and may be a composite sample. Samples shall be collected from locations that appear to be representative of the dust level in the system.
- (ii) Local exhaust ventilation systems shall be assumed to be non-compliant if the zone in which they are located is non-compliant or sampled to determine whether they are. Exhaust flues and chimneys are non-accessible areas.
(e) Use of Composite Sampling. - (i) Samples from individual locations can be combined into one composite sample for analysis. The result for a composite sample shall be interpreted to indicate the level of target compound residue present throughout the zone of the composite. The number of subsamples in one composite shall not exceed the number which can be analyzed within the laboratory's QA/QC limitations. Adequate recovery of the Target Compound(s) for the maximum number of subsamples in composites shall be verified by unknown spiked samples.
(f) Sampling for Lead and Mercury. - (i) If evidence indicates the possibility that amalgam methods were used to manufacture methamphetamine or other target compounds (e.g., the phenyl-2-propanone method, or any method that evolves mercury or lead residues), lead and mercury shall be additional Target Compounds for that Clanlab. A minimum of three mercury air samples shall be collected throughout the assessment area. Sampling for lead in dust shall comply with 40 CFR 745.227.