David,

By all means use a respirator, but you should be able to shoot the clear outside in order to provide an additional margin of safety. The paint fumes will be harmful to the members of your household as well should the enter from the garage. It is also wise to keep the parts outside or at least in the garage while they are curing since they are still giving off toxic fumes while this process is going on. I usually shoot early in the morning or in the evening when it is relatively calm, and I spray Yard Guard to keep the bugs away. You can hose the yard down in order to minimize the dust. A cloudy day is a bit better since bright sunlight may blush the clear as it is being sprayed, although I have never experienced this problem.

Mike Danchak