BS ISO 8502-15:2020 Preparation of steel substrates before application of paints and related products一Tests for the assessment of surface cleanliness – Part 15: Extraction of soluble contaminants for analysis by acid extraction.
6.2.7 Transfer the solvent to a suitable vessel for analysis (see Figure 6) as required for the analysis method.
6.2.8 During steps 6.2.3 to 6.2.7. it is essential that no solvent be lost from the cell or syringe, due for instance to inferior-quality materials or improper handling of the materials. If any solvent is lost, the solution obtained shall be rejected.
6.2.9 On completion of step 6.2.7. clean and rinse the syringe so that it can be reused. A bent needle is best left as it is until it becomes necessary to straighten it or bend it further.
6.3 Extraction by sleeve by pre-filling
6.3.1 Take an adhesive sleeve (51..) of a suitable size (see Table 1). Remove the protective paper and straighten the sleeve.
6.3.2 Prefill the sleeve with the required volume of solvent (5) and adhere the patch to the surface without loss of solvent (see Figure 7).
NOTE The volume of solvent needed to fill the sleeve compartment is proportional to the compartment area and normally amounts to 10,0 x 10-3 mi/mm2 ± 0,6 x 10-3 mi/mm2.
6.3.3 Position the sleeve such that all solvent in the sleeve is in contact with the surface.
6.3.4 During a suitable period of time, to be agreed between interested parties, or recommended by the manufacturer of the test equipment, agitate the sleeve several times by massaging the solvent on the surface. After the time period, let the sleeve hang down in order for the solvent to flow into the compartment of the sleeve.
6.3.5 Carefully remove the sleeve from the surface. Retain the solvent for further analysis.
6.3.6 During steps 6.3.2 to 6.3.5, it is essential that no solvent be lost from the sleeve, due for instance to inferior-quality materials or improper handling of the materials. If any solvent is lost, the solution obtained shall be rejected.
6.3.7 Record the temperature of the steel surface to the nearest 0,5 °C using the contact thermometer (SA). The temperature shall be over 0 °C to avoid ice on the surface.BS ISO 8502-15 pdf download.