They make their own use, installed in a personal residence, does not count, belongs to the individual handmade hobby, personal research, worth encouraging.

Their own production, given to others to use, installed in public, that is illegal, "Special Equipment Safety Law"

Their own production, for profit purposes sold to others, the first one is the crime of shoddy products, and secondly, the violation of a whole lot of industrial and commercial administrative laws and regulations, oh, there are also special equipment related to the law

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