ProCal Primary Turbidity Standards have been certified by HF scientific for use in the Hach® 1720 c/d/e Series Online Turbidimeters. No formazin is used, making the standards safer, easier to use, accurate and less expensive that the equivalent Hach® product.
In addition to being approved by the EPA, ProCal™ has been certified through testing conducted by HF scientific demonstrating that ProCal™ performs as well as Hach® primary turbidity standards in selected Hach® instruments. Test results are available upon request. Hach® is a registered trademark of the Hach Company, which is not affilitated with HF scientific.