At Sentry, we take safety very seriously and it is our number one priority! Sentry’s CEO was a former aerospace structural engineer as well as a former CEO of an existing car seat company and was heavily involved with the testing of Guardimals booster seats in the government certified crash testing facilities. The National Highway Traffic Safety Administration (NHTSA) sets the standard for safety requirements for ALL automobiles and safety equipment that are used with automobiles. All car seat manufacturers MUST follow their FMVSS213 specification for safety. Sentry Guardimals booster seats have passed or exceeded all FMVSS213 government safety certification requirements.
How Harness Weight Affects performance
Many people think that the higher the harness weight, the safer the seat. This is not necessarily the case. Injury values that can demonstrate the safety of a car seat are determined during crash testing. One of the most important injury values involves the head (HIC) and chest G levels experienced by crash dummies. This is basically the gravity forces transferred to the test dummy based on a few factors – the main one being how quickly does the dummy come to a stop in a child restraint system placed in a crash sled. If the seat has more give to it, the Gravity forces will transfer to the dummy at a lower rate – Like crumble zones in a car. So a seat that has some flexibility will usually produce lower crash G’s. Seats that are stiffer do not flex as much and the G’s are usually higher. The FMVSS 213 allowed level of chest G’s are capped at 60. Some car seats will have G levels far below the allowable producing a lower crash environment on the dummy, and some will be very close to the allowable. Seats with higher allowable harness weights tend to be stiffer because they are designed to hold a higher weight with the harness. These seats can result in more g forces transferred to the crash dummy. So just because a seat boosts a higher harness weight, some up to 90 pounds, this could result in higher chest G’s than a seat with a lower harness weight limit that transfers sooner to a belt positing booster. The harness benefit is clear up to levels around 50 pounds but is much less significant above 50 pounds when compared to the Belt positing configuration. However, all seats that meet the government’s FMVSS213 safety requirements are considered safe. Sentry Guardimals crash test results were significantly below the allowable levels, thus decreasing the crash environment transferred to your child.
1) Here’s what Car Seat Blog says about this in their article “Mythbusters: 5-point Harnesses Are Safer than Boosters for Older Kids”: (provide link)
Let’s look at the studies that have compared properly fitting seat belts (meaning in a booster for kids age 5 and up) and 5-pointharnesses in similar crash circumstances:
That’s right, there aren’t any. Zip, zilch, zero. So that will make this a bit more challenging.
There are a number of studies that compare children in 5-point harnesses to seat belts alone and a number that compare children in belt positioning boosters to seat belts alone, and even one Canadian study that compared boosters with a 5-point harnessed seat but with a dummy that was heavier than the weight limit of the harness. But none that compare children in 5-point harnesses to children in belt positioning boosters for older kids. One study did show a modest benefit of a 5-point harness over boosters for 3-year olds, but showed much smaller benefits for 4-year olds and concluded, “The results for any type of injury support the recommendation for graduation at 4 years or about 40 pounds in general, although it may be the case that more severe injuries are better prevented by CRS (Child Restraint System with harness) even at 4 years old.”
So despite the past research, we don’t have any firm evidence to tell us whether older kids (5+) are safer in boosters vs. forward-facing 5-point harnesses. l’m sure it will be no surprise that in the studies that exist, both 5-point harnesses and high back belt positioning boosters both reduce the risk of injuries to children as compared to seat belts alone.
2) Here is what Kid Safety First has to say about “CAR SEAT SAFETY RATINGS – THE NHTSA MYTH”. (add link)
Looking for the Safest Car Seat
When my wife was pregnant with my twins boys I spent hours and hours searching the internet trying to find out which of the many car seats would be the safest. This is obviously a perfectly natural thing for any first time parent to do. Even before you have ever met your baby, the desire to protect them is overwhelming and a few hours research seems a very small price to pay for finding “the” safest car seat.
Did I find “the” safest car seat? – No!
Have I found it since? – I’m afraid not!
Why? – there are NO independent and comprehensive safety tests that can be used to proclaim that any seat is objectively safer than another.
So, if you are reading this post because you are hoping to find a safety ratings list that will make the difficult task of finding “the” safest car seat, then I’m afraid that you are going to be disappointed. You will very often read reviews claiming that “Seat A has a better safety test score than Seat B” or that “Seat A has an excellent NHTSA safety rating”. You should ignore anything that these people say because they are either ignorant of the truth or deliberately misleading you. If you think about it for a moment, if there was such an ordered “ratings list” you could be pretty sure that the company manufacturing the seat with the highest safety rating would be screaming this fact from the rooftop! Yet, there are no screams because there is no such ordered list of safety ratings. The truth is that all car seats that are currently available to buy on the US market meet Federal Safety Standards & strict crash performance standards. Now, that doesn’t necessarily mean that they are all as safe as each other, but the problem is that there are no comprehensive independent standardized test scores to enable you to know which seat is the safest.
The NHTSA Myth
Whilst there may be some unscrupulous people on the internet that are deliberately misleading parents on this issue, I suspect that most people that perpetuate this myth do so innocently and because they have either heard other people saying it or misunderstand the nature of the car seat tests that do actually exist.