My Child is jumping out of the Straps (even it's tight enough)
Children are copy-cats. They watch your every move so closely and repeat it to see what happens when they do it. You're aware of them doing it a lot of the time - many people avoid swearing in front of their children, some people don't like arguing in front of them, you allow them to see you using the loo and brushing your teeth by way of encouragement of what they need to learn.
So what about when they copy the bad stuff? Stuff that we, as parents, need to do, but stuff that they really shouldn't. Stuff like opening the oven, pouring boiling water from the kettle, opening the buckle of their harness on their carseat.
Well, it's down to parental guidance: "Don't touch the oven", "Don't play with the kettle", "Don't undo the carseat harness". Most often than not, you'll follow up that statement with a reason - "Don't touch the oven - it's hot, and it might burn you". It's the same with the carseat harness buckle - you have to provide a reason why it's important for them not to undo it.
There are various pages set up on the internet to help parents with techniques for discouraging children from undoing their carseat harness; Tips such as making it into a game, demonstrating to them how everyone must wear a seatbelt and explaining the importance for it on a level that the child can understand, whether they're a curious toddler or a bored six year old. In addition, distraction techniques can be helpful, and for younger children the Maxi Cosi PlayTray will fit onto all the Group 1 carseats in the range, providing not just entertainment but also making it more difficult to access the red release button.
The Maxi Cosi carseat range requires a pressure of 60 Newtons of force to open it. This is the maximum allowed under UK safety law so we can't make it any harder to undo. To make it more difficult for the child to undo the harness, always ensure that the harness is adjusted to the appropriate height for their shoulders (it should be no more than an inch above or below their shoulder height) and also check before every journey that the harness has been properly tensioned. You should only be able to fit 2 fingers between the childs chest and the harness once it is correctly tensioned as per the user manual. While the child may not like being restrained in the carseat harness, you aren't hurting them by ensuring it's correctly tightened before each journey, and you must remember in the event of an accident you want the harness to be nice and secure to prevent them flopping around in the carseat.
The harness must be completely released by a single, red push button. This is the universally recognised seatbelt and carseat release button, and in the event of an emergency if someone other than yourself needs to get the child out of the carseat quickly they need to be able to do so easily and without specific guidance from yourself on how to do it, so adding things to the harness is not advised and some additional chest clips are in fact not legal for use under UK law.
If you're on a long journey and the child falls asleep, you may find that the harness appears looser on them than it did when you first set off - this is as they've relaxed, and as the harness is not self-retracting like an adult seat belt it may become loose as their posture changes in the seat. In this event, if you were to have an accident at this point, the harness would prevent the child from moving any further forward from the position they were originally in; the carseat harness has not loosened off at all. In the event that you're concerned about the amount of additional gap when the child falls asleep, pull over when it is safe to do so and give the tensioner strap that extra pull to remove the slack. If you're not sure that you are able to fit the carseat and tension the harness correctly, please refer to the website for video demonstrations on fitting the carseat, or ask your local retailer for a refresher lesson in how to correctly fit and tension it.
These sites are worth having a look at if you encounter the issue of your child trying to get out of the harness, whether they are releasing the red button or attempting to slip out of the harness any other way: