Colmembername(IAQ_OHSUM,0,54)

Hello Linda

Thank you for your question and welcome to the forum.

This is not a standard Excel function, nor does it appear to be a function that would be available if you installed any of the Excel Add-ins. It is most likely that it is a bespoke function which has been written using VBA code, in which case we unfortunately cannot shed any light on what it does - sorry.

Kind regards
Amanda