AWWA B703-19 pdf download.Fluorosilicic Acid
4.3.1 General. The material supplied according to this standard shall contain no mineral or organic substances in quantities capable of producing deleterious or injurious effects on the health of those consuming water that has been properly treated with the material.
4.3.2 Free acid content. The fluorosilicic acid supplied according to this standard shall contain a maximum of 1 percent free acids (other than fluorosilicic acid), expressed as HF (hydrofluoric acid).
4.3.3 Product certifications. Fluorosilicic acid is a direct additive used in the treatment of potable water. This material should be certified in accordance with the requirements of NSF/ANSI 60. Appendix B lists the impurities typically checked under NSF/ANSI 60 for fluorosilicic acid, the US and Canadian drinking water standards for those impurities, and the single product allowable concentration (SPAC) for each impurity. The SPAC is the allowable concentration of the impurity in the treated water when the material is added to give a fluoride concentration of 1.2 mg/L (current) or 0.7 mg/L (recommended).
5.1.2 Amount of shipment to be sampled. If the acid is supplied in drums, the number of drums sampled will be left to the discretion of the purchaser. In the case of bulk shipments, a composite sample should be taken from the tank truck or tank car.
5.1.3 Sampling container. Samples shall be collected in a clean, plastic or rubber container. Containers lined with acid-resistant plastic, wax, or rubber may also be used.
5.1.4 Sampling method for drums. When sampling from drums, the fluorosilicic acid in the containers to be sampled shall first be mixed by rolling or other suitable means. A portion shall be taken from each container to be sampled so that the total gross sample consists of at least 2 L.
5.1.5 Sampling method for bulk material. When sampling from a tank truck or tank car, at least five different 500-mL portions shall be taken from different places in the container (top, middle, and bottom) and combined to form a composite sample that is representative of the entire container. 5.1.6 Sample handling. After mixing of the gross sample, three 500-mL samples shall be sealed in airtight, moisture-proof, plastic or rubber containers. Each sample container shall be labeled to identify it, and the label shall be signed by the sampler.AWWA B703-19 pdf download.