Then, you may think that if you wear a pair of glasses to prevent the ejected material from getting directly into your eyes when you cut, it will not stain your eyes.
However, wearing glasses has no effect at all. Glasses are completely useless. The reason is that the juice from the onion does not fly directly into your eyes. The component that stings the eyes evaporates immediately when the onion is cut and turns into gas. Ordinary eyeglasses do not prevent the gas from being released, so even if you wear eyeglasses, the gas will be released regardless of whether you are wearing eyeglasses or not.
If you wear underwater glasses instead of ordinary glasses, this should be quite effective. This is because underwater glasses cover the eyes so tightly that gas cannot get in. However, the gas emitted from the onion is quite strong and irritating not only to the eyes but also to the nose. In this case, even underwater glasses will not stop the runny nose.
Although it is not possible to prevent the onion from irritating the nose completely, there are several ways to make it much less irritating.
One of the first is to let the onion cool before cutting it. It has been shown that the colder the onion is, the less likely it is to produce this gas.
Another is to cut the onions while soaking them in water. This gas has the property of dissolving in water, so if you cut onions while soaking them in water, the amount of gas will be reduced considerably.
Another thing to do is to use a sharp knife. If you use a sharp knife and cut quickly, the amount of gas produced will not be so great.
Another method is to ventilate the room well.