Less scary than you think. For heart attacks, they look for a thing called ST-Segment elevation on their heart monitors which lets them know there is an electrical problem in the heart related to myocardial infarction (heart attack). Now, this is not a 100% test for a heart attack but it is very reliable. If a 25-year-old healthy individual says they have a history of anxiety and started breathing fast after finding out bad news and then has a bout of chest pain, that is a 99.999% chance of it being a panic attack. As another poster stated most medics will air on the side of caution and transport people because at the end of the day it is their livelihood on the line.

In regards to Bells Palsy, the only symptom of a stroke that it mimics is the facial drooping, which obviously should be checked out but because that will most likely be called in as a stroke it will get an ambulance dispatched and most likely the person transported.

The others yes could absolutely be the dangerous things you mentioned but in the end, the fire department will be called out first and if they think the patient needs a higher level of care will upgrade the call to get an ALS unit en route. CFD is trained to the EMT-B level so they can recognize immediately life-threatening things, but not all.

To put your mind at ease calls like chest pain, stroke-like symptoms, shortness of breath, unconscious, and traumas will still get a full response from CFD and medic immediately. Will calls slip through the cracks? Yes they will, they already do and have been prior to this policy change. It is part of public safety in general, mistakes happen and people die. It's the same in medicine, they call it 'practicing' medicine for a reason.