AWWA B503:2017 pdf download.Sodium Tripolyphosphate
5.2.1 Laboratory examination. Samples to be analyzed for phosphorus content have a maximum holding time of 28 days. Terefore, the laboratory exam- ination of the samples should be completed as soon as possible after receipt of the shipment (Sec. 5.1).
5.2.2 Test procedure for size. For powder and granular materials, weigh 100 g of sample and screen on the appropriate US Standard Sieve Series, then weigh the amounts of material passing through or retained on the sieves.
5.2.3 Test procedure for solubility. Weigh 10 g of sample and add slowly, while stirring, to 100 mL of distilled water at 50°–100°F (10°–38°C). Stir moderately for 30 min, after which time all material should, by visual determination, be dis- solved. Filter through tared, dried glass-fber flter of the type used in total suspended solids. Wash the beaker with distilled water. Using the same distilled water, wash the residue with six 25-mL portions of distilled water. Dry the flter and residue at 221°F (105°C) for 1 hr and weigh. Report the increase in weight (as a percentage of the original sample weight) as insoluble matter (for example, 0.02 g equals 0.2 percent).
5.2.4 Test procedure for P 2 O 5 content. Phosphorous pentoxide (P 2 O 5 ) content shall be determined by the pH titration method described in the following paragraphs. As an alternative, the procedures presented in Sec. 5.2.5 may be used. If discrepancies between the methods develop, the titration method in Sec. 5.2.4 shall govern.
5.2.5 Alternate test procedures for P 2 O 5 content. Phosphorous pentoxide content shall be determined either by the method described in Sec. 5.2.4 or by the quinolinium phosphate method described in detail in the following sections. Purchasers may also use methods from Section 4500-P in Standard Methods for the Examination of Water and Wastewater, latest edition. If discrepancies between the methods develop, the titration method in Sec. 5.2.4 of this standard shall govern.
If the material delivered to the purchaser does not meet the chemical, physi- cal, safety, or security requirements of this standard, the purchaser shall provide a notice of nonconformance to the supplier within 5 days after receipt of the ship- ment at the point of destination. Te results of the purchaser’s tests shall prevail, unless the supplier notifes the purchaser within 5 days after receipt of the notice of nonconformance that a retest is desired. On receipt of the request for a retest, the purchaser shall forward to the supplier one of the sealed samples taken in accor- dance with Sec. 5.1. In the event the results obtained by the supplier do not agree with the test results obtained by the purchaser, the other sealed sample shall be forwarded, unopened, for analysis to a referee laboratory agreed on by both parties. Te results of the referee analysis shall be accepted as final.AWWA B503 pdf download.