ADA does not require covered entities to modify policies, practices, or procedures if it would “fundamentally alter” the nature of the goods, services, programs, or activities provided to the public. Nor does it overrule legitimate safety requirements. If admitting service animals would fundamentally alter the nature of a service or program, service animals may be prohibited. In addition, if a particular service animal is out of control and the handler does not take effective action to control it, or if it is not housebroken, that animal may be excluded. ADA requires that service animals be under the control of the handler at all times. The service animal must be harnessed, leashed, or tethered while in public places unless these devices interfere with the service animal’s work or the person’s disability prevents use of these devices. In that case, the person must use voice, signal, or other effective means to maintain control of the animal. Under control also means that a service animal should not be allowed to bark repeatedly in a lecture hall, theater, library, or other quiet place. However, if a dog barks just once, or barks because someone has provoked it, this would not mean that the dog is out of control. If a service animal is out of control and the handler does not take effective action to control it, staff may request that the animal be removed from the premises (https://www.ada.gov/resources/service-animals-faqs/)