A person utilizes a gas mask apparatus for personal protection against harmful air particles and contaminants, such as asbestos or dangerous chemicals, which can damage lung functions and cause serious health problems. Other workers use masks to administer oxygen, anesthesia or other medical needs to patients before beginning types of surgical operations.

Anesthesiologists

Anesthesiologists work in operating rooms administrating treatment to patients for operations. This medical worker uses a gas mask on the patient, delivering anesthesia through the apparatus to prevent the patient from feeling pain during surgery and place them into a comatose state. After the administration of anesthesia through the gas mask, the patient is allowed to awaken in a hospital room.

Hazardous Materials Removal Workers

People obtain jobs as hazardous materials removal workers, commonly referred to as hazmat workers. The employees may remove, transport or dispose of radioactive waste, nuclear waste and other dangerous materials that could harm the public or the environment. Hazmat removal workers wear full protective suits along with respiratory-type gas masks when removing hazardous material from buildings and the environment. Types of respirators the workers may wear include self-contained units attached to protective suits that supply air, or simple apparatus pieces that cover the nose and mouth, according to the United States Bureau of Labor Statistics.

Firefighters

Firefighters risk their lives to save people during dangerous emergencies such as house fires and traffic accidents. When entering a burning building to put out the blaze or look for trapped people, firefighters use gas masks that supply them with fresh oxygen. Once a person has been located and removed from a building, the firefighter will also administer oxygen through a gas mask to help the person who may be experiencing smoke inhalation.

Dentists

Another profession where a worker uses a gas mask involves dentistry. Dentists treat teeth and gum problems in the mouth using an assortment of tools. When a person needs oral surgery, such as root canal work or implants for dental appliances like dentures, the dentist may use a gas mask on the patient. The dentist administers anesthesia to dull the nerves in the patient's mouth so the person will not experience any pain during the surgery.