Health Function Scale

Health Function Rating Scale

Most of Interior Medicine rates products on their materials: what they're made of and how those materials affect your health. Those ratings scales are all here.

But some products earn their place in your home by doing a specific job, and that job is itself the health benefit. A blackout curtain's job is darkness, which protects your sleep and circadian rhythm. A shower curtain's job is resisting mold and water. A radon detector's job is catching a colorless, odorless carcinogen before it builds up. When a product fails at that job, the health cost is real, regardless of the materials its made with.

The Health Function scale rates how well a product does the health job it exists to do. It runs from Highest to Lowest and stays consistent across each product category. What earns each tier is defined separately for each category, since blocking light and detecting radon aren't measured the same way. You'll find the specific criteria on each product's page at the top of the FAQ. Here is the general structure all are based on: