Passive smoke exposure (PSE) is carcinogenic, linked to cardiovascular and respiratory diseases, increased risk for sudden infant death, and increased severity of asthma, and is generally harmful.^1,2

According to the behavioural ecological model (BEM), smoking and passive smoke exposure are behaviours influenced by interacting physiological, environmental, and cultural contingencies.³ Social models, criticism, and praise serve as powerful reinforcing contingencies of lifestyle practices. These interact prominently with physiological and community based contingencies. For instance, once an individual is prompted by the industry to start smoking, nicotine addiction adds physiological consequences for smoking (for example, increased alertness) and for not smoking (for example, increased anxiety). These interact with social contingencies promoted by the industry, media, and social reinforcement from members of personal networks to strengthen the addiction. The strength of the addiction is dependent on the biological addiction to nicotine and the density of reinforcement from social networks. Fortunately, other social networks include people who oppose tobacco smoking, and provide reinforcement for avoiding tobacco, possibly countering the industry influences. These include culture-wide sanctions.

Culture-wide “values” define social contingencies that may delimit smoking. One of the more prominent is protecting infants and children from harm, especially if suffering from disease (for example, asthma). To the extent that PSE is viewed as harmful, the community is likely to criticise parents who allow their children to be exposed, especially if very young, ill, or in their own home.

At the legislative level, community policies and related policing and penalty systems can contribute to both direct change in …