I did my 6 month stint in the paint shop at the fire engine coachbuilders where i work as an apprentice last year and can tell you that for 2 pack paint you must have an air fed mask,though we used to paint by brush
without it,you can thin it down so that no marks are left with the brush.
im not sure what H&S would say though.
Cellulose(excuse if incorrect spelling) is a lot safer and does not require the mask but is till worn in the booth.
Two pack tends to leave a hard brittle finish where as cellulose is softer AND has a longer timespan before polishing is nigh on impossible(the paint hardens and wont buff up.
Ill be honest in thati try to brush or coach paint most of my things if possible,i use a black gloss gargae door paint,suitiable for all metals for exterior use,looks just like the proper stuff at around £3.00 for a large tin.
