At Aperture Science, we take safety very seriously. After all, you could get hurt and then we'd have to go out and hire a new person. What a waste of all those hours we spent training you! So here's a hat. It's bright orange so it matches your jumpsuit. It says "Test Subject" on the side so you'll always remember how important you are to Science. It will provide a degree of protection should a gel or other compound land on your head, but it will not -- we repeat, WILL NOT -- protect you from falling cubes or other large debris. So, y'know, look up once in a while, okay?
Bright Aperture orange ball cap with white trim and white embroidered Aperture logo. "Test Subject" written on the edge of the brim.