Depends on where you are. In America, not one. In Holland, various forms of cannabis can be obtained and used legally. I can't think of a single place where smoking opium is still legal. So -- check the local laws.
It is legal to own a shisha pipe in the UK. However, it is not legal to use it to smoke substances that it is not legal to possess. But as an ornament there is no problem.
Nicotine
It is legal to smoke marijuana in public. It is only legal is it given by the doctor.It is legal to smoke medicated marijuana in public. You should only smoke what the doctor told you too.
It's perfectly legal to have any smoking devices (including hookahs) in your house. However not legal to smoke any illegal substances out of them. As long as your keeping it for the intention to smoke seisha (hookah tobacco) out of it, you have no reason to keep it from anyone including the police.
If we're talking about marijuana and other smokable drugs, then absolutely. Just like secondhand cigarette smoke can enter your lungs and effect you, so can smoke from controlled substances.
There are many substances in cigarette smoke, but the most popular ones are Butane and Methane. These chemicals are released in cigarette smoke and can cause many health issues.
There is no question that there are poisonous substances in all forms of smoke, and breathing it can be harmful.
Most of the substances are those in gas form inhaled by the person. A classic example is nicotine for when you smoke cigarettes. The smoke also irritatates the system.
Anything that is legal in the civilian world.
Legal smoke is smoking "incense". They found a way to derive the active ingredients in marijuana and put into a legal form. Then it is mixed as an incense or "Spice".
Because smoke contains microscopic particles of dust, ash and other substances.
Because smoke contains microscopic particles of dust, ash and other substances.