What do accrediting agencies such as NSF ensure when it comes to equipment?

NSF does not regulate or require that your product be certified. However, U.S. health departments, end users and buyers often specify NSF certification to ensure that products have been evaluated and tested, and comply with public health standards.

Explanation:

Hop you find this helpful :)

(a) i got it right on the test

there is not really a certain expensive film type but i believe all of them cost mostly the same price, i hope this a little bit