Child seats, the law, and what we actually fit

In an ordinary car, a child must normally use an appropriate child restraint until they are twelve years old or 135 centimetres tall, whichever comes first. After that a seat belt is required in the usual way. The restraint has to be suitable for the child weight or height depending on which standard the seat is built to, and it has to be correctly fitted, which is where most of the real-world failures happen.

Those are the rules people know, and they are the ones that apply to almost every journey a family makes. The exception that matters here applies to licensed vehicles, and it is much narrower than the way it is often used.

Where a child seat is not available in a licensed taxi or private hire vehicle, a child aged three or over may travel in the rear using an adult seat belt, and a child under three may travel in the rear unrestrained. That is the exemption, and it exists so that a family is not left on a pavement at midnight because a vehicle carries no seats.

It is a safety net, not a standard. A three-year-old in an adult belt is legal in a licensed vehicle and is not as well protected as a three-year-old in a proper seat, and everybody in this business knows it. The exemption is why some operators do not carry seats; it is not a reason for a parent to accept one.

• Private car: a child restraint until twelve years or 135cm
• Licensed vehicle without a seat: three and over may use an adult belt in the rear
• Licensed vehicle without a seat: under three may travel unrestrained in the rear
• The exemption is a fallback, not a standard to plan around

Infants travel rear-facing, and rear-facing seats need space, which is why a rear-facing seat behind a tall front passenger is a genuine geometry problem in a saloon. Toddlers move to a forward-facing harness seat. Older children use a high-backed booster, which positions the adult belt correctly across the shoulder and hip rather than the neck and stomach.

The one to be careful about is the backless booster cushion. It raises the child but does nothing about the shoulder belt position and offers no side protection, and it has fallen out of favour for good reason. Where a booster is needed we fit a high-backed one unless you specifically want otherwise.

If a booking arrives for four children in a vehicle that cannot take four seats, the answer is a bigger vehicle or two cars rather than a compromise. We will not put a child in a position where the seat cannot be fitted properly, and we will not use the licensed-vehicle exemption as a way of squeezing a family into a car that is too small.

The other case is a seat we have not seen. If you arrive with a seat that cannot be installed securely in the vehicle, because of the belt geometry or a missing part, the chauffeur will say so rather than fit it approximately. That is an unwelcome conversation and it is the right one.

And on a very short journey where a family would genuinely rather use the exemption, we will carry them legally within it. It is your decision, not ours, and we would rather be plain about what it means than pretend the option does not exist.

• Two small children usually means a V-Class rather than a saloon
• A rear-facing seat costs a usable front passenger position
• Bring your own if the child prefers it, and tell us so
• We will not fit a seat that cannot be installed properly