I recall noddy suits and respirators being a fairly regular feature of the first couple of days. In addition to Scuds, they were firing anything that went bang, and much that didn't, from the Al Faw before they cleared out. I thought Seersucker was some sort of fabric until one landed up the road. At that time, everyone was taking the chemical threat pretty seriously, though I don't recall wearing NBC kit after the unit entered Iraq on a permanent basis on Day 3.
Prior to the fun, there were a few drills, including one at the port in Kuwait where we were collecting vehicles. We suited up while the dockworkers opted for the NBC shemagh option and put their head dress over their mouths. The CO instructed us to drive out while we were in full rig so as not to get caught up in further festivities and our appearance caused an interesting ripple effect on some of the military we drove past.
At Arifjan during the build-up, someone sent a fake IED to the post office with a note saying 'Glad you don't have the kit you need'. This was at one end of a hanger containing a thousand or so troops, mostly American, and everyone was evacuated. While standing outside, someone stuck their mask on and the Protect and Survive equivalent of a Mexican Wave rippled up and down the line a couple of times.
We know now that the WMDs were a figment of the CIA's imagination, that Tony Blair is a lying, duplicitous, streak of slime and that the Iraqi Army was a paper tiger but it's easy to forget at this distance and with hindsight that,, at the time, the prospect of fighting in a chemical fog whilst tip-toeing through a vast mine-marsh was a very credible scenario for the invading forces.