I would barely be comfortable with 2 hours but 90 minutes would scare me.
I did this in March (arrived T5 on UA, departed T1 on UA, but same process) and I think it took me at least 65-70 minutes to get airside again. OP doesn't say when the flight is, but keep in mind that ORD is frequently hit by thunderstorms in the summer. Delays can be common.
Originally Posted by
Swiss Tony
The TSA were understaffed and downright rude
To be fair, this has happened to me at Heathrow too. I was screamed at by a screener ... my offence? I was a business class passenger who wasn't told at check-in that there's a premium passenger line, so I was in the regular line.
It's not so much her attitude that bothered me, it's that if I spoke to her the same way, I'd be in jail. You Brits have even fewer rights at the airport than we do, which I didn't think was possible.