Passenger airbags were first introduced into vehicles in the 1970’s in the USA and in the 80’s in the UK. Passenger airbags have proven to save lives and increase the safety for a passenger if you are involved in an accident. For some situations, you should turn the passenger airbags off such as if using a rearward facing car seat on the front passenger seat. This is because if the airbag is activated it can cause the car seat to be pushed up and into the back of the seat which can be fatal.
Some cars are fitted with an airbag deactivation switch allowing you to turn the airbag on and off depending on which passengers you are carrying but many vehicles need to be taken into a dealership to have this deactivated or to have a switch installed.
Ideally, try not to put a child seat on the front passenger seat as it is thought not to be as safe as putting them in the back.