Scientists have found that smoke-free legislation has positive effects on the health of children. Both preterm births as well incidence of asthma has been declined as result of banning smoking in public and work places.
It’s widely known that second-hand smoke as dangerous as smoking itself. Classical liberals in the tradition of John Stuart Mill, believe that adults should be free to do whatever harm to themselves; but if their actions would harm non-consenting others, then the government is justified to interfere. This rule is known as the harm principle.
Smokers do, by exposing others to their smoke, cause harm. That smokers inflict harm to themselves, is from a Millian perspective irrelevant as long as it is their own choice. What matters is the harm done to non-consenting others. Especially in case of children.
Children are because they not yet able to make their decisions, dependent of adults. If people smoke in the presence of children, the latter have little or no means to protect themselves against this violation of their right to health. Therefore the state should take action.
The research cited above about the positive effects of smoke-free legislation in Western countries, suggest that Space Settlements should take the ultimate step: complete prohibition of smoking. That means outlawing the sale smoking devices and, of course, smoking itself.
Since this prohibition is aimed at the protection of third parties, and not against the use of the drug nicotine per se, the sale and consumption of products such as nicotine patches, inhalers and nicotine gum, should be legal. Also the sale and consumption of smokeless tobacco products should not be be affected by the total smoking ban.