Terms defined in SDCL 36-25-1 and Chapter 2 of the Uniform Plumbing Code, 2024 edition, have the same meaning when used in chapters 20:54:19 to 20:54:28, inclusive. The following terms have the meaning indicated when used in chapters 20:54:19 and 20:54:28, inclusive:

1. (1) "Administrative authority," the individual official, board, department, or agency, established and authorized by a state, county, city, or other political subdivision, created by law to administer and enforce article 20:54;
2. (2) "Bypass," a connection or a valve system that allows raw water to be supplied while the water conditioner is being cleaned or serviced or the media changed;
3. (3) "Capacity," an amount expressed in total gallons of water treated, meeting a manufacturer's specifications and produced in a defined period of time;
4. (4) "Cation exchange," in water softening, principally the exchange of calcium and magnesium ions in water for sodium ions on an insoluble ion exchange material;
5. (5) "Corrosion," the attack by water on any part of a water system, causing the wasting away of metal parts;
6. (6) "Disinfection," the process of destroying harmful microorganisms, done in accordance with section 609.10 of the Uniform Plumbing Code, 2024 edition;
7. (7) "Drain line," a line used to carry backwash water, spent regenerant, and rinse water to a waste system;
8. (8) "Effluent," the water or solution that emerges from a water conditioner during any phase of the operating cycle;
9. (9) "Filter," a device installed as part of a water system through which water flows for the removal of turbidity, taste, color, or odor;
10. (10) "Hardness," dissolved calcium and magnesium salts in water;
11. (11) "Installation," the piping or valving by which water conditioners are connected into the water supply system, including a drain line;
12. (12) "Ion exchange," a process whereby ions in solution are interchanged by a reactive material;
13. (13) "Medium," the active material in a filter;
14. (14) "Raw water," water at the inlet of the water treating unit;
15. (15) "Regeneration," in general, the backwash, brine, fresh water rinse, and maintenance steps necessary to prepare an exchanger bed for service after exhaustion, and specifically, the brine step in which a sodium chloride solution is passed through the exchanger bed and sodium ions displace hardness ions from the exchanger to permit the hardness to be rinsed to drain;
16. (16) "Rinse," part of the cycle of a water conditioner operation in which water is introduced to remove spent backwash water or regenerant, or both, prior to placing the conditioner into service;
17. (17) "Soft water," water containing less than one grain per gallon of dissolved calcium and magnesium salts, as calcium carbonate equivalent;
18. (18) "Turbidity," any undissolved materials in water; and

19. (19) "Water softener," a device installed as part of a water system, which produces soft water by cation exchange, removing calcium and magnesium or hardness from flowing water and replacing it with sodium, thereby requiring periodic regeneration with sodium chloride or salt.

    Reference: Uniform Plumbing Code, 2024 edition, International Association of Plumbing and Mechanical Officials. Copies may be obtained from the International Association of Plumbing and Mechanical Officials, 5001 East Philadelphia Street, Ontario, CA 91761. Copies may be viewed free of charge at https://epubs.iapmo.org/2024/UPC/.

Source: SL 1975, ch 16, § 1; 12 SDR 91, effective December 2, 1985; 12 SDR 151, 12 SDR 155, effective July 1, 1986; 23 SDR 83, effective November 28, 1996; 29 SDR 52, effective October 20, 2002; 30 SDR 99, effective December 22, 2003; 38 SDR 40, effective September 20, 2011 ; 43 SDR 31, effective September 12, 2016; 52 SDR 42, effective October 28, 2025 .

General Authority: SDCL 36-25-15 .

Law Implemented: SDCL 36-25-15 .

Prior versions effective: 2016-09-12, 2011-09-20.