The official database is typically delivered as:
A comprehensive 2020 guide by Herman Behls providing tools for fan sizing and noise minimization. ashrae duct fitting database pdf patched
There is no legitimate "patch" released by ASHRAE for a PDF. The phrase likely refers to user-modified spreadsheets (Excel or Google Sheets) where someone has manually entered the database coefficients and then "patched" known errors using errata sheets from ASHRAE Research Project 1053-RP. The official database is typically delivered as: A
: Contains loss coefficient tables for over 200 round, rectangular, and flat oval fittings. Visual Aids and flat oval fittings. Visual Aids