I am re-writing my department's pre-plan forms, and want to do them in Microsoft Excel. I want to incorporate ISO's required fire flow formula in the spreadsheet to calculate basic fire flow. This formula seems to be pretty complex, and so far has resisted my efforts in trying to get it into a cell. Does anyone have a working excel spreadsheet that does this?

By the way, I'm interested in results and not particularly hunk up on the ISO formula. I'd like to see what the rest of the world is doing in regards to using a spreadsheet to calculate required fire flows.