Cybex Sirona S

The Cybex Sirona S struggles in ease-of-use and fit-to-vehicle for a variety of reasons. It is challenging to manage the various straps, tensioning arms, and the seat itself while trying to secure the seat with either the LATCH strap or the vehicle belt. Additionally during installation, it is very easy to inadvertently release the seat into the belt path and obscure its access. When installing the seat, one has to carefully balance achieving just enough tension for a secure installation with too much tension that could prevent the tensioner door from closing. Once installed, the swivel feature and harness adjustments work well. While the load leg feature provides some crash benefit, it does not put it at the top of its class. 
 

Consumer Reports has developed a new crash test that offers consumers comparative performance information on which car seats could provide an additional margin of safety when compared with other models within the same ratings group that have been subjected to the same test protocol. Our Crash Protection Ratings are based on injury criteria measured on standardized child-size dummies, contact of the dummy’s head with the back of a simulated front seat and a car seat’s ability to remain intact during the course of testing. Consumer Reports’ new crash tests are not designed to check whether a seat complies with current federal car seat safety standards. Rather, the purpose of our new tests is to differentiate the seats’ performance on a scale that ranks the performance of tested seats ranging from “basic” to “best.” Our focus on providing an “extra margin” of safety, rather than on determining whether a seat is safe or not, is based on the fact that any car seat sold in the U.S. already must provide an essential level of safety under the government standards. The new test conditions were carefully designed to simulate the interior environment and forces encountered during a crash in contemporary vehicles. Changes from the way that convertible seats were rated previously include using a test bench that better simulates the vehicle seat design from a contemporary vehicle, with more representative cushion stiffness and seat geometry and incorporation of a “blocker” to simulate a front seatback. The new test also runs at a higher 35mph speed, with other representative dynamic characteristics that better simulate the behavior of contemporary vehicles during a crash.
 

The Cybex Sirona S is part of the Car Seats test program at Consumer Reports. In our lab tests, Harnessed Car Seats models like the Sirona S are rated on multiple criteria, such as those listed below.

Ease of use: Our judgment of how easy each seat is to use including the clarity of labels and instructions, adjustments of clips and buckles, the transition of the seat between modes and installation features such as LATCH connections, belt paths, top tethers and booster guides.

Forward facing fit-to-vehicle: A rating of how compatible, easy and secure a child car seat can be correctly installed in the forward-facing direction. This rating is a combination of the LATCH system and belt ratings that are available individually on the model page.

Rear facing fit-to-vehicle: A rating of how compatible, easy and secure a child car seat can be correctly installed in the rear-facing direction. This rating is a combination of LATCH system and belt ratings that are available individually on the model page.