If you cannot use these types of solvents in a well ventilated area, then use a respirator. Most indoor use of these chemicals is very dangerous to your health over the long term, read all labels and follow safety instructions, if you can smell it, it can hurt you. I do not use anything stronger than isopropyl alcohol, ever. It is strong enough to remove almost all deposits and powder residue. For the bore I use a mechanical type of cleaning solution, it scrubs away all fouling and no fumes to kill brain matter. Volatile organic compounds can kill you very quickly, or very slowly over time, much worse to your health than smoking. There is also another reason to use these types of chemicals in a well ventilated area... if you have pilot lites or even static discharge the fumes could ignite in a flash fire that is bad news for anyone around.