I think the tag refers more to the frequencies listed. If they are on business frequencies, they should be listed as "business". If they are on PS frequencies, they would be listed as EMS.
There really is no way to make a better distinction. But, business frequencies should not be used for 911 dispatch calls. I know in some places they ARE, but they should not be since 911 dispatch users should not violate FCC rules by waiting for other users to finish using the frequency, but they also should not delay calls because the trash company is talking about the location of the dumpsters at the local pizza place. That's why PS frequencies exist - for PS users who are (usually) much less long-winded compared to business users.
Case in point: If a local business (using business frequencies) responds to HazMat calls, should they be listed as business or HazMat? Should tow trucks be listed as business or Emergency Ops if they tow accidents?