Imagine you have a toy that you really love to play with, but some of the parts are broken or not working well. You could keep playing with it and hope it doesn't get worse, or you could try to find new toy parts that work just as well, or even better than the old ones.
Now imagine that the toy is actually something much bigger and more important, like a machine used by a lot of people to do important work. Sometimes the parts used to make this machine may not be the best for the environment or for people's health. That's where the Significant New Alternatives Policy (SNAP) comes in.
The SNAP program is run by the U.S. Environmental Protection Agency (EPA), and it helps make sure that companies are using safe and environmentally friendly materials in things they produce, like machines or chemicals. When companies want to use a new type of material or chemical, they have to prove to the EPA that it's safer and better for the environment than what they've been using before.
Basically, SNAP helps make sure that we keep using the toys we love, but with better, safer parts that won't hurt us or the environment.