The common system of using domestic gas cylinder bottles with the carp (i.e the burner and valve complete set inserted in to gas cylinder bottle as single gas stove) on top to cook  is dangerous on its own.

Very common in many  countries such as in India, Pakistan, Nigeria, South Africa and other Asian countries.

That should be discourage.

Cooking direct with Cylinder is a time bomb. If you want to be safe in using  gas cooker go for table gas if you can't afford the set.

In terms of safety keeping the  gas cylinder in a well ventilated area is very important. However, how do one use his/her 3kg, 5kg, 6kg and probably 7kg single gas cylinder stove with a top because you can't separate the cylinder from the stove?

Again, this is dangerous for indoor usage. LPG gas cylinder bottles was not made to be use in close doors, it was  made for camping and travel.

There is what you can do. When you finished from cooking, start by closing gas cylinder first ,then the stove will automatically turn the flame off, to ensure that gas is finished in pipes,then turn the On/off knob to off position.

If there's a gas leak....or you're smelling gas: 

3. And don't use a cellphone....just close the valve. 

Until the smell vanishes....so no explosion. 

Even if you were cooking while the pot overflow..... flames went off. Just switch off the gas immediately.

Adding on what is said. Always practice SAFETY around gas cylinders - around any explosive. Put safety measures in place at home. It start with you. Try by all means. 

LPG gas is in high demand, going foward people should practice safety. Again on my street, there is a guy filling cooking gas cylinders. People refill there in a space/location and environment of where people make use of lighters -  smokers and drunkers. Avoid such places as well as possible.