What a button test is
Short answer: A button test measures how much force it takes to tear off a button, a rivet or a snap fastener. The requirement applies especially to parts on garments with a lot of strain. The test shows whether the fastening or the fabric gives way first.
Why buttons are tested
A button that falls off is more than a small annoyance. It can get lost, and the garment may be useless without it. That is why buttons, rivets and snaps are tested in the laboratory, so you know how much they take before the clothes reach the shop and everyday life.
The force is measured with a grip
The button is gripped by a holder and pulled straight out from the fabric. The machine notes the force at the point where it comes loose. The pull is even and in a fixed direction so results can be compared. It is a plain measure of how well the button holds, without guesswork.
Both button and fabric can fail
Either the fastening opens, or the fabric tears around the button. The two kinds of break tell you different things. If it is the button, the thread or fastening may be too weak. If it is the fabric, there is not enough support around it. See also bamboo tennis socks for women.
Reinforcement behind the button helps
A small fabric reinforcement behind the button spreads the force over a larger area. Instead of all the load gathering in a few stitches, it is shared out, and the fabric holds better. If the requirement is not met, reinforcement is often a simple fix that can be tested again. See JBS of Denmark and Bamboo Basics.
Snaps and rivets
Snap fasteners are tested both for staying closed and for opening. They should not pop open on their own, but should not need too much force to open either. Rivets are tested like buttons, because they also have to stay in the fabric. Each has its own requirement depending on where it sits.
The requirement depends on the garment
The test applies especially to parts on garments with a lot of strain. A button in a trouser waistband takes far more load than a decorative button on a blouse. So the requirement is not the same everywhere, and it is set by where and how the button is used.
What a break tells you
When the sample has failed, you look at how. Did the thread snap, the fabric tear or the fastening spring open? That points to what needs to change. The test is used not only to pass or fail but also to improve how the button is sewn on.
Can you test it at home
You can pull gently on a button and feel whether it sits firmly, but without a machine you get no number. Look instead at whether the thread is dense and crossed, and whether a small fabric reinforcement sits behind. Those are signs the button has been attached properly.
Frequently asked questions
Why is the test important
Because a loose button can end up somewhere it should not, and because the garment loses its function without it. The test shows beforehand how much force the button takes, so it can be corrected before the clothes are sold.
Does it apply to snaps as well
Yes. Snap fasteners are tested both for staying closed and for opening. It matters that they neither pop open on their own nor are far too hard to open in everyday use.
Can you test it at home
You can pull gently on the button, but without a machine you get no number. You can check whether the thread is dense and crossed and whether a small reinforcement sits behind the fabric.
