tax write offs? for travelers

I am trying to find out info to give to my accountant regarding what can
be written of for travelers. i am the only travel nurse he handles and he is questioning the legality of some of the things i have mentioned to him. i have heard a wide variety of what we can use from:
gas, scrubs, $10/day for meals, hotel expenses during travel, etc.
any info on this matter would be appreciated. also if anyone has a great accountant that he could speak with as a reference that would be great!
rachel, rn