I am having trouble sorting my column C from largest to smallest in time.

I need a way to format it quick because my program scrapes in seconds, minutes, and hours.

S=Seconds
M=Minutes
H=Hours

Here is a screenshot:
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I can't sort based on numbers because my numbers have different units. I need to be able to do it quickly because I have a lot of data that I'll be working with so if theres a way that I can tell excel that S is seconds, M is minutes and H is hours and then with a click of a button to sort from highest to smallest that'd be great. Can anyone advise please.