Section 761.395 - A validation study(a) Decontaminate the following prepared sample surfaces using the selected testing parameters and experimental conditions. Take a standard wipe sample of the decontaminated surface.(1) At least one uncontaminated surface. The surface levels of PCBs on the uncontaminated surface must be <1 [MICRO]g/100 cm2.(2) At least seven contaminated surfaces.(b)(1) Select applicable method(s) from the following list to extract PCBs and determine the PCB concentration from the standard wipe sample collection medium: SW-846 Method 3540C, Method 3550C, Method 3541, Method 3545A, Method 3546, or Method 8082A (all standards incorporated by reference in § 761.19 ). Modifications to the methods listed in this paragraph or alternative methods not listed may be used if validated under subpart Q of this part.(2) Report all validation study surface sample concentrations on the basis of micrograms of PCBs per 100 cm2 of surface sampled.(c) Following completion of the validation study, measurements from the contaminated surfaces must have an arithmetic mean of [LESS THAN EQUAL TO]10 [MICRO]g/100 cm2 . If the arithmetic mean is >10 [MICRO]g/100 cm2, then the validation study failed and the solvent may not be used for decontamination under §761.79(d)(4) according to the parameters tested.