How do I tell my friend his smoking is effecting my asthma?

Rabin R asked:I recently beendiagnosis w/ asthma. Today I almostpass out fromsecond hand smoke @ work. Myco-worker smokes butalsolethisclothes smoke withhim–Afterhissmoke breakI literally havetoleave –heknows I haveasthma –howcanI tellhimwithout [...]