Even K36 uses isocyanates.
take a look at this, about 3/4 of the way down.......positive pressure ONLY!
http://www.cdc.gov/niosh/npg/npgd0423.html
Just to clarify, there are color coats that use isocyanates and those that do not. I use K36 for primer (has isocyanates), then a non-isocyanate color coat and then an isocyanate clear coat.