Your definitely going to want to bring everything everyone else above has said....
-safety manual
-team safety plan (if you don't have one, create one. Even if you don't have it ready to go this year, tell the judges you're going to to implement it next year)
-first aid kit
-enough safety glasses for everyone + extras for visitors
I'd also find the MSDS sheets for your batteries and throw them in the binder with your safety manual/safety plan. Bring some baking soda as a part of your "emergency battery leak kit." Your batteries won't leak, but it's better safe than sorry and the safety judges love that. Work gloves and possibly ear plugs to cover all of the PPE bases.
Create an "injury log" sheet, so you have a written record of who gets hurt, how they got hurt, and what they took it out of the first aid kit. You can also use this to find weaknesses in your overall safety plan. If people keep getting hurt doing the same things over and over again, what can you do to change it?
Our team also makes "emergency contact cards" with everyone (students/mentors)'s phone numbers, the hotel phone number, and a place to write down an emergency meet up spot at both the hotel and the competition in case of a fire or what not. Hand them out to everyone on the team and parents before you leave.
Depending on the regional, you might also want to create a sign-in/sign-out policy. At BMR we allow students to go out in groups to lunch or on a walk to get out of the loud environment, but they have to sign in and sign out first with an estimated time of arrival. We use a library catalog-like system, but find something that works for you.
Other than that, just keep a clean pit, make sure your team is following safety rules, and make sure no power strips are plugged into other power strips. That's the equation I've been following for the last 3 years and we've won the UL Safety Award @ BMR for those 3 years too. Good luck
