I find it sad that people who, as part of their chosen profession, are expected to interact with and show basic respect for people of extremely diverse cultures, religions, backgrounds, and socioeconomic status are being so, well, disrespectful.
You may take issue with Islamic tenets, but who cares? Don't convert. About "religions that tell you what you can look like"...
1 Timothy 2:9 (NIV): "I also want women to dress modestly, with decency and propriety, not with braided hair or gold or pearls or expensive clothes."
1 Corinthians 11:14: "Does not the very nature of things teach you that if a man has long hair, it is a disgrace to him."
Deuteronomy 22:5: "A woman must not wear men's clothing, nor a man wear women's clothing, for the LORD your God detests anyone who does this."
Leviticus 19:27: "'Do not cut the hair at the sides of your head or clip off the edges of your beard."
Christianity, Islam, Judaism... you'll find restrictions on dress and appearance in every major religion. Of course these are all subject to interpretation and some followers will abide by them and some will not, but they're all there.
Obviously having a beard in EMS may be problematic. The issues here are safety and hirability... not which religion is right or wrong.
Legally... according to Title VII of the Civil Rights Act of 1964... "It shall be an unlawful employment practice for an employer to fail or refuse to hire or to discharge any individual, or otherwise to discriminate against any individual with respect to his compensation, terms, conditions, or privileges of employment, because of such individual’s race, color, religion, sex, or national origin..."
The important language comes in the definition of religion... "The term “religion” includes all aspects of religious observance and practice, as well as belief, unless an employer demonstrates that he is unable to reasonably accommodate to an employee’s or prospective employee’s religious observance or practice without undue hardship on the conduct of the employer’s business."
It's that "undue hardship" part that's up for interpretation. It could be very easy for an employer to claim undue hardship based on potential safety problems and the cost of accommodating a beard.
Title VII
Here is an interesting case regarding two Islamic Newark police officers who refused to shave their beards (Federal court ruled in their favor).