1.1 This practice covers the calculation and adjustment of calcium, strontium, and barium sulfates for the concentrate stream of a reverse osmosis or nanofiltration system. The calculations are used to determine the need for scale control in the operation and design of reverse osmosis and nanofiltration installations. This practice is applicable for all types of reverse osmosis devices (tubular, spiral wound, and hollow fiber) and nanofiltration devices.

1.2 This practice is applicable to both brackish waters and seawaters.

1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.