I am 2 months pregnant and currently manage an office that conducts fieldwork in nursing homes, licensed, and unlicensed board and care homes. Does my employer have to accomodate my request to limit the amount of field work due to exposure to second hand smoke in unlicenced board and care homes and infectious diseases(such as shingles in nursing homes), if the field work is a minor part of my job? I currently only need to go out in the field about 10 percent of the time, and I can delegate this to my staff who is able to handle the task. The field work entails interviewing residents, sometimes staying at one site for 3-4 hours in a smoke filled environment.

If you're thinking ADA and reasonable accomodations, no. Pregnancy is not, except in VERY rare circumstances (and if those circumstances applied you probably wouldn't be working at all) considered a disability for ADA purposes and accomodations are not required.

That being said, did your employer already refuse the request or are you just looking for information?

Thank you for the information. I have not asked my employer yet.

Then I'd suggest seeing what they say. If they refuse, come back and we'll see if we can help you at all, but right now I think the best thing to do is give them an opportunity to work with you.