Cars not only take over the space they need for moving, they also have a zone of influence which expands as speed and the quantity of traffic increases. This has the effect of shrinking the home territory of residents and depriving them of a sense of privacy. Children lose the street and pavement to play in, and people drive instead of walk, using their cars as a refuge from the unfriendly environment. Social interaction in the street decreases. Neighbours visit each other less often, and know fewer of the other homes and residents in the street. As traffic increases people are often forced to abandon the front rooms and front gardens of their homes because of the noise, dust and vibration of the traffic. The street is then used solely as the corridor between the sanctuary of individual homes and the outside world of work, shopping or recreation. The last step is that people may move to a quieter area of town or move to the country. Those that stay have retreated into a "neighbourhood relationship poverty". Those who move in cannot afford to rent or buy elsewhere. For these people the lack of neighbourhood friendship links is another cost to pay for being poor.
Especially for households on roads with heavy traffic flows and where living space extends of necessity into the street, the dangers to young children are acute. In many cities, traffic accidents are the chief cause of death among children over one year of age.