NSF certifies drinking water filters to standards applicable to each type of treatment option. You may notice the NSF mark on a product along with numbers such as NSF/ANSI 53 or NSF/ANSI 42, which refer to the standard to which the filter has been certified.
The definition of a canon is a principle, law or standard by which people are judged or a member of the clergy living according to these principles or laws. An example of a canon is a moral principle that a group believes is correct or proper.
As we learn more about these two, we begin to have an idea of what they might be running from. It turns out that the Canon and his Yeoman, or servant, are alchemists â people who try to turn metals like lead and iron into gold through chemical processes â and not particularly good ones.