NSF 60 Revisions Purkiss December 4, 2013

Update on Chlorate SPAC established in NSF 60 – 2012 = 200 ppb. SPAC calculation did not utilize all sig figs of MAC risk assessment which would have resulted in a SPAC of 300 ppb. Rounding rules have now been clarified in NSF 60. Ballot to correct SPAC passed the NSF 60 JC but failed the CPHC by 3 votes.

Update on Chlorate Correct derivation of SPAC based on 4 sources of chlorate source water hypochlorite chlorine dioxide or ozone one unknown source SPAC = 1.12 mg/L = 0.28 mg/L = 0.3 mg/L (rounded) 4

Update on Chlorate NSF International has tested 127 hypochlorite samples from Jan-Oct samples passed 200 ppb limit. –65 Mfrs and 20 Repackagers. 42 samples failed 200 ppb limit. –9 Mfrs and 33 Repackagers. 33% of samples failed for chlorate 12% of samples from manufacturers failed. 62% of samples from repackagers failed.

Update on Chlorate 18 failures are between ppb. 12 failures are between ppb. 5 failures are between ppb. 2 failures are between ppb. 4 failures are between ppb. 1 failure is between ppb. 43% of failed samples are in disputed range of ppb.

Reduction in Max Use Level in terms of ppm total chlorine Most hypochlorite products are listed at a MUL that equates to a total dose of 10 ppm chlorine. Reducing MUL for products failing for chlorine would result in the following: # ProductsChlorate ppb Reduced Chlorine MUL ppm ppm ppm ppm ppm

Chlorate SPAC If the chlorate SPAC was properly set at 300ppb it would reduce the failures from 42 (33%) to 24 (19%). Resulting MUL reductions as follows: # ProductsChlorate ppb Reduced Chlorine MUL ppm ppm ppm ppm

Chlorate SPAC Chlorate formation continues at significant levels in distribution, storage and handling to point of use. Compliance with the chlorate standard has to be a shared responsibility between producers, distributors and end users. AWWA standard provides recommendations to control chlorate levels through temperature control, dilution on receipt, inventory turns, etc. Therefore control should be focused on user practices as AWWA recommends.

Chlorate SPAC 2013 data indicates that implementation of the current SPAC for chlorate could severely impact the user population. Recommend to re-ballot SPAC correction to 300 ppb.

Bromate and NSF 60

Bromate SPAC Table D1: the drinking water regulated level (MCL/MAC) for bromate should be changed from 0.01 mg/L to mg/L to conform to the number of significant figures reported by the US EPA in the derivation of the MCL. The SPAC for bromate should consequently be changed from mg/L (5 ppb) to mg/L (3.3 ppb) based on the mg/L MCL and derivation per Annex G and rounding rules.

Bromate SPAC The SPAC for bromate referenced in should be reduced from 5 ppb to 3.3 ppb as noted above. The SPAC for “low bromate” in should be lowered from 3 ppb to 1.0 ppb. Alternatively “low bromate” could be removed from the standard. Annex G should be deleted, as it announced the lowering of the SPAC for bromate effective January 1, 2013, and so is no longer needed. Replace with a note describing what it addressed.

Hypochlorite Literature Requirements If the MUL for a hypochlorite product is lowered due to a bromate failure section of the standard currently requires a statement in manufacturer’s literature stating that the MUL has been lowered and why. NSF 60 does not require this for any other product or contaminant other than bromate in hypochlorite. It also goes above and beyond product requirements and is addressing a certification practice. Therefore this should be removed from the standard.

Hypochlorite Literature Requirements Section contains requirements for manufacturer’s literature regarding the use of hypochlorite with respect to controlling the amount of chlorate and perchlorate. This requirement should be restricted to literature that references NSF 60, and not all literature that might accompany a shipment.