Regarding the bellows torch that we use in Thailand. They have
evolved quite a long way in the past few years . Now the system has
two bottles and a torch which is available in three different sizes.
One bottle contains gasoline the other is for mixing the gasoline and
the air . There is now a net over the rubber on the bellows so that
the tire cannot pop. We have used them for seven years and have
never had a problem with safety (knock on wood) however they must be
used with good ventilation. In many parts of Asia such as China and
Tibet they still produce the single bottle torch which is inferior to
the Thai product.