Children and airbags in vehicles
You should check with your vehicle manufacturer for their recommendations on the use of child seats when airbags are fitted.
Within existing legislation (provided they are in an appropriate child restraint) it is not an offence to place children in the front seat of of a vehicle.
However, the Driver and Vehicle Standards Department (DVS) recommends that children are not placed in the front seat of any vehicles fitted with airbags.
UK Department for Transport website
Information about children and airbags on the UK ROSPA website