According to the text, hearing ear dogs don’t

                                   Service Animals

A Therapy Dog is a kind of service animal – an animal that helps people. The most common service animal is a seeing eye dog. A seeing eye dog helps blind people. However, dogs help people in many other ways. Hearing ear dogs help people with hearing problems. These dogs listen for specific noises, such as a fire alarm. When the dog hears the sound, the dog touches the owner. However, if it’s an emergency, the dog may pull the owner out of danger. Usually small dogs are hearing ear dogs because they are easy to care for. Wheelchair assistance dogs are much larger because the dog’s main job is pulling the wheelchair. These dogs also open doors and get items for their owners, such as magazines.

                                                       (Adapted from Access Reading – Thompson)