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39 NACE INTERNATIONAL: VOL. 56, NO. 10 MATERIALS PERFORMANCE OCTOBER 2017 outlined in ASTM D4940. 12 Figure 5 shows measured test levels for chlorides, sulfates, and nitrates. This represents a small but meaning ful spot check of commercial abrasives used commonly for surface preparation. Condi- tions of pressure, particle size, friability, and hardness can all contribute to transfer levels. The results in Table 1 can be com- pared with those in Table 2, which were from small samples of various commer- cially used abrasives received two months prior and were analyzed for chloride, sul- fate, and nitrate contamination with the s a m e f i e l d t e st k i t m e t h o d o u t l i n e d previously. The test results in Table 1 can be com- pared with prior published tests using doped abrasives to certain chloride con- tamination levels to determine transfer rates and in order to provide some initial guidance on limits, which may be consid- ered "safe" for not transferring soluble anionic salt species to the substrate. These include: FIGURE 1 Extraction for chloride, sulfate, and nitrate detection. FIGURE 3 Abrasive blasting of test panels. FIGURE 2 Sample collection: (a) collecting measured sample; (b) transferring sample to extraction container; and (c) autovial sample filtration. FIGURE 4 Combined "CSN" and "A" kits. FIGURE 5 Test measurement levels: (a) chloride, (b) sulfates, and (c) nitrates. • Research conducted at Transport SA (Adelaide, South Australia) calcu- lated a limit of ~20 mg/kg (ppm) of chloride before transfer to blasted substrates occurs. 13 • A European Commission report was i n t e r pre t e d a n d e xtra p o l a t e d t o ref lect a level <20 mg/kg (ppm) of chloride as a limit before transfer occurred. 14 A f u r t h e r d a t a p o i n t i s t h e l i m i t ref lected in the 11127 series of ISO stan- dards, which specify a limit of 25 mg/kg (ppm) of chloride from various abrasives. No details were found to validate the basis for this data.