Drabkin's Diluent - Manual Hbometry Applications

540nm absorbance quantifies 7-23 g/dL Hb across anemia screening in resource-limited settings preventing microhematocrit error.

Hematology laboratories calibrate spectrophotometers using NIST SRM 921 confirming accuracy across high-altitude correction factors.

Quality control verifies methemoglobin conversion, ferricyanide potency, and 24-month stability. WHO-validated prevents regional variation.