If you are making/developing evacuation plans, then why not be perfectly clear and use " evacuationplans.com "

evacplan.net or evacuplan.com

Even though the domain name is longer, I agree with Richard that evacuationplans.com would be even better if you want people to find you by search engines. Having your search terms in the domain name gives your site a boost in the search engine listings.  If you will do search engine optimization, using the full word ¨evacuation¨ in the name is helpful.

Or maybe PlanEvacMap.com? Because the evacuation map is often used phrase too.