If you enable someone who is not  a Gas Safe-registered engineer to inspect or work on a fuel boiler, cooker or fireplace in your home, they would possibly not be qualified to do the work safely. http://nguyenkhuyen-nuithanh.edu.vn/index.php?language=vi&nv=news&nvvithemever=d&nv_redirect=aHR0cHM6Ly93d3cubWV0b29vLml0L3UvNjZhZGI0ZDZmM2ZlMjMxMTYwMjcwNGNk