Just for the record, there is no cheap mask available that can stop isocyanates. They're heavier than air so will lie lower to the ground, but they are present in 2k hardener and therefore the mixed paint.

1k paints are fine as the thinners can just give you a headache.

The only way to avoid isocyanate is to use a proper air fed filtered mask/hood. They're expensive, but its the only proper way. If you have ventilation along the ground this will help them dissipate.

Low level exposure for short periods of time shouldn't have any long term effect, but some are more sensitive than others. Once you've had enough to give symptoms you will be over sensitive for the rest of your life.

http://www.hse.gov.uk/mvr/myths/myth3.htm

Be safe kids.