Health Based Cleaning Limit Calculation

Hello everyone,
I found this formula for calculating product residues and I want to know if anyone else is using it? How is it working for you. Is FDA ok with this?
Swab limit = ADI(mg/day) x Batch size (mg) x test area(cm squared) X recovery factor / Max Daily Dose-MDD (mg) X Shared Surface Area-SSA (cm squared)

thanks!