All adult family members and adolescents should take an X-ray (photofluorogram) of the chest; young children should pass a PPD test. Preventive measures may also include drug administration.
Another important component of TB prevention is a compliance with infection control regulations in the room.

Sanitariness of a TBC patient’s room

The destruction of causative agent requires continuous ventilation, ultraviolet irradiation and wet cleaning of a room. If a room is sun-facing, it is sufficient to open the windows. If not, there is a need for artificial ultraviolet irradiation using special ultraviolet lamps that you can buy in medical equipment stores. One should perform a wet cleaning of a room, wash the curtains and laundry to remove dust where Mycobacterium tuberculosis is housed.
If a TBC patient lives with you in one apartment, it is a good idea to give him/her a separate room, cooking utensils and underwear. The form of coughing must be strictly observed by a sick man - the mouth and the nose should be closely covered with a napkin when coughing and sneezing; the patients should wear surgical masks in public places. The patient must spit out the sputum into a special container with a lid (preferably disposable spittoon glasses). The sputum is decontaminated directly in a jar with a solution of chlorine (you can use the home laundry detergent "Bilyzna" which contains a high concentration of chlorine); closed jars with decontaminated sputum and napkins used by the patient should be thrown into the trash container. 
If you're at a hospital, you should wear a surgical mask throughout the entire treatment period. This way you do not only infect the common air but protect yourself from re-infection when you inhale foul air due to other patients' failure to obey courtesy rules.

Infection occurs only by inhalation of air infected by a sick person who failed to practise proper hygiene.