AWWA B503:2005 pdf download.Sodium Tripolyphosphate
4.3.3 Product certifications. Sodium tripolyphosphate is a direct additive used in the treatment of potable water. This material should be certified as suitable for contact with or treatment of drinking water by an accredited certification organization in accordance with NSF/ANSI 60, Drinking Water Treatment Chemicals—Health Effects. Evaluation shall be accomplished in accordance with requirements that are no less restrictive than those listed in NSF/ANSI 60. Certification shall be accomplished by a certification organization accredited by the American National Standards Institute.
5.1.2 Sampling device. Sodium tripolyphosphate in powder form shall be sampled using a sampling tube that is at least 3 / 4 in. (19 mm) in diameter. Granular forms of the material shall be sampled by scoop only. Bulk shipments, such as by railcar, shall be sampled by taking an adequate number of grab samples (at least five) during the unloading process.
5.1.3 Amount of shipment to be sampled. Five percent of the packages or containers shall be sampled, but a minimum of 5 packages and a maximum of not more than 15 packages in any one shipment shall be sampled. No sample shall be taken from a broken package.
5.1.4 Sample size and handling. The gross sample, weighing at least 10 lb (4.54 kg), shall be mixed thoroughly and rapidly and shall be divided to provide three 1-lb (0.454-kg) samples. These samples shall be sealed in airtight glass containers. A label identifying the sample shall be affixed to each sample container, and the label shall be signed and dated by the sampler. A chain-of-custody form shall accompany all samples and shall be properly completed by the individuals collecting samples.
5.1.5 Test samples. Test samples shall be obtained from sealed material samples collected in accordance with Sec. 5.1 of this standard. Material samples shall be unsealed only when it is necessary to remove quantities of the material for testing. Material shall be removed quickly, and the material sample shall be resealed for future reference.
5.1.6 Retention. Samples shall be retained for at least 28 days after they are received before they are discarded.AWWA B503 pdf download.