You ever find yourself in a situation where the external regulator attached to your gas cylinder bottle makes gas leak after installation, however small?
If a leak is suspected through the regulator, it could be from a faulty regulator. There is no fixed lifespan for LPG pressure regulator. Sometimes they continue to give good service and sometimes some developed mechanical trouble (getting stuck while turning on and off).
Also, gas leaks may be from connecting pipe not properly fitted on the cylinder valve. With no flame "ON", remove the seal cap from through automatic valve, place the regulator onto the valve and push down firmly and vertically. You should totally able to hear a "CLICK" sound, which means the regulator is securely fitted to the gas cylinder bottle.
Lastly, check whether the sealing rubber (O-RING) is in place inside the gas cylinder valve by feeling the same with the help of your little finger tip. Not inserting inner rubber into the cylinder valve, can cause gas leak through the regulator. Gas leaks can cause fires or explosions. It is recommended that sealing O-ring rubber should be replaced with new one after a refill at the gas plant. You may say "but I just recently changed this!!". Well, have you ever consider the fact that rubber do expands? LPG well cause natural rubber and some plastics to deteriorate.
Do not attempt to use cylinder bottle if you suspect gas leaks through the regulator. Turn off the regulator knob, then switch off appliance. Contact your distributor immediately.