Hi, I put MA in my pool to lower high Alk plus a stubborn PH that kept rebounding high every other day. I drizzled it undiluted into the 1" return jet (16 ft above ground pool) as one of the moderators suggested. I did not have wind blowing in my face or anything. The next day I felt chest tightness, and kept coughing. I suppose it could've been allergies, but this is unusual for me and since it was the very next day, I strongly feel it was caused by breathing the MA, although I did not smell any strong smell while drizzling it, but then again I've been stuffy lately. Are you supposed to dilute it in a bucket before drizzling it? Or drizzle at full strength? Another pool web site mentioned one should wear a respirator for acid? I found one on Home Depot's website (3M Tekk) http://www.homedepot.com/h_d1/N-5yc1vZ1 ... ogId=10053 but out of the items it says it protects againsts (Mold, Lead, Coatings and solvents, Chlorine, hydrogen chloride, sulfur dioxide, hydrogen fluoride or hydrogen sulfide.) I don't see MA (hydrochloric acid). Or does it fall under one of the ones they mention? (I'm no chemist) If this one won't do, can someone advise me on a good respirator?