Parents often ask if it's safer to 'double up' their child restraints by using a RideSafer travel vest AND a backless booster seat at the same time. The short answer is no - here's why...
While a conventional backless booster seat elevates your child to fit the adult seat belt, the RideSafer travel vest brings the adult seatbelt down to fit your child. One of the great safety features of the RideSafer travel vest is that it allows your child to maintain a lower centre of gravity compared to a conventional booster seat, which can reduce the severity of whiplash injuries in an accident. Using a conventional booster seat would reverse this feature.
The RideSafer vest has been crash tested and certified as a harness restraint under the American FMVSS-213 standard. It has not been designed nor crash tested to be used in conjunction with a third party booster seat. Conversely, the third party booster seat also hasn't been designed nor crash tested to be used in conjunction with a RideSafer vest.
The RideSafer vest uses metal seatbelt guides to appropriately position the adult seatbelt across your child's body. Using a third party booster seat at the same time may skew the position of the adult seatbelt - this can have three significant implications:
(i) it may change the position of the seatbelt relative to your child's body which may inhibit the vest from properly protecting your child in an accident;
(ii) it may cause the seatbelt to twist or fold which can localise crash forces onto that part of your child's body; and
(iii) it may increase the risk of the seatbelt slipping out of the seatbelt guides.