Acronym Definition
HWC Hazardous Waste Combustor
HWC Handle With Care
HWC Hispanic Women's Corporation
HWC Hydrogen Water Chemistry
HWC Health & Wellness Center
HWC Hardware Configuration
HWC Hazardous Waste Coordinator
HWC Harmonized Wage Code
HWC Heavyweight Champion
HWC Head-Wind Component
HWC Hunter Water Commission (Australia)

I've never heard the term/acronym, but from my experience I would hazard the same guess as the first responder...Handle With Care.

OP, does this sound right? Was there a situation that maybe had you labeled as meriting special attention in this instance?