LPG gas is stored in liquid form in a steel container, cylinder or tank - and connected through a hose pipe from the regulator outlet to your kitchen appliance that is being fuelled. For a permanent use outside the house, LPG tanks/bottles should always be kept in vertical position outdoor and just connected to the appliance by permanent piping. This would greatly reduce the risk of leaks and explosions. For example, if the connection to the cylinder leaks, if outdoor, it usually just dissipates.
When the regulator knob of the BBQ gas cylinder is turned on, it releases the gas into the supply appliance. There is only one way for the gas to flow through the hose pipe and it reaches the gas stove. So, the knob and the regulator are operated by a simple method.
Never leave the gas cylinder bottle connected in "ON" position. Do not leave the regulator in "ON" position after cooking is over or during night. They can blow over the burner and catch fire with any trigger. The valve on the LPG cylinder and the appliance knob allow the gas to pass through the regulator to the gas stove. Always remember to switch "OFF" the LPG cylinder regulator outdoor after cooking, then go to switch "OFF" the appliance switch indoor. Do not switch off the gas stove appliance last, the gas cylinder bottle should be the first thing you turn off, because this then cut off gas supply immediately.
Also, always check the rubber tubes associated with your LPG cylinders. They should not be damaged or found to be leaking.