I'm going to get too technical for a brief moment. SOLAS is not a "done deal", but is just in the planning stages. One problem with it is legal and jurisdictional impairments in ANY government or group thereof trying to control ships while on the "open seas." Solution will be a long time in happening, as it will be a major departure from the age-old principle of freedom on the high seas. Yes a government like the US could pass a law banning smoking in ships' staterooms -- but that law would only apply as long as the ship were within the "12 mile limit" of US jurisdiction. Beyond that, the US would be without jurisdiction and authority to regulate anything that goes on in a stateroom. (The way ships open and close their casinos depending on whether they are in jurisdictional waters of countries that ban gambling is an example)
See? Not repetitve at all, right?