When a totally or partially blind, totally or partially deaf, or physically disabled person is accompanied by a dog which serves as an assistance dog or which is being trained by a qualified trainer as an assistance dog, as defined in section 24-34-803 (7), C.R.S., for such disabled person, neither the disabled person nor the dog shall be denied the facilities of any common carrier, nor shall such disabled person be denied the immediate custody of the dog while riding upon a common carrier. The provisions of this section shall also apply to any qualified trainer who is training a dog for use by a totally or partially blind, totally or partially deaf, or physically disabled person, unless the dog presents an imminent danger to the public health or safety. Such disabled person or any qualified trainer who is training a dog for use by a disabled person shall be liable for any damage done to the premises or facilities of the common carrier by such dog. Any dog being trained for the purpose of aiding a disabled person shall be visibly and prominently identified as an assistance dog in training.