Why Is Milk White?: & 200 Other Curious Chemistry Questions (2013)
4. Health and Safety
Humans use a lot of chemistry to keep healthy and safe. They have disinfectants for kitchen and bathroom surfaces but also for their skin. They protect it with lotions and creams and wash off germs (and the things germs eat) to stay healthy.
People also protect themselves from the chemicals they use. After all, we are made of chemicals, and chemicals react with one another. Knowing something about how chemicals behave can keep us safe while we use them.
Why do people need to wear goggles while they are doing experiments?
Because they want to keep their eyesight. Many experiments in chemistry are fairly safe. When we do experiments with food, for example, we usually don’t need to wear protective eyewear. If a little salt or pepper gets in your eye, it might hurt, but the tears that come will safely wash the food away. But when we start to do experiments with chemicals such as acids, alkalis, or abrasive powders or when we heat something up, we want to protect our eyes from the hot or caustic materials.
We also wear protective gloves when we work with some chemicals or when we work with hot things. But while the skin on your hands might heal and only leave a scar, that doesn’t stop you from using your hands. Damage to the eyes does not heal as easily, and you can have permanent damage to your vision.
Protective clothing is a good idea when working with most chemicals. It doesn’t hurt to be safer than you need to be, and some experiments with harmless chemicals might produce things that are harmful. Keeping long hair away from flames is a good idea—tie your hair back so it doesn’t fall into the flame.
Most protection is common sense. We wear gloves when using strong household cleansers like bleach. We wear dust masks when using sandpaper on plaster walls or when spraying paint. We wear eye protection whenever there is a danger of flying particles or droplets getting into our eyes.