For normal souring, add 1-2 ounces per 50 pounds of linen into final rinse cycle. Safe to use in conjunction with softeners and starches. Use the PDQ Universal pH Indicator to ensure final pH is between 6.0-7.0. Consult your service technician for exact usage. For reclaiming discolored linens, disconnect all dispensing equipment to be sure that the sour is not mixed with other chemicals. Add 8-16 ounces per 50 pounds of linens into a hot water cycle. Allow to agitate for at least 15 minutes. Allow machine to complete the remainder of the wash cycle to provide ample rinsing of linens. Check pH of finished linens. If pH is lower than 6.0, rinse the linens again or until the final pH is above 6.0. When finished, re-connect dispensing equipment.