Lots of companies will sell you formaldehyde detectors, but a simple test you can do at home will reveal they are fakes. Formaldehyde detectors routinely react to lots of common gases that are not formaldehyde, making the numbers basically impossible to interpret. Given that unfortunate fact, here’s what you can do to test formaldehyde in your home.
Have you ever moved into a newly remodeled apartment and smelled that chemical, remodeling smell?
I’m very much not an expert in air pollution, but I am very much a dedicated nerd. And I’ve spent the last five years of my nerd energy on researching and testing formaldehyde in China. This series shares the three most important things I’ve learned.
Lesson 1: If you can smell it, you’ve got a problem. Don’t waste time and money testing.
If you can smell that sort of chemical, paint, or cleaner smell, you have a VOC problem in your home.
Although I’ve seen people say that formaldehyde is colorless and odorless, the fact is it has a strong smell.
I know from my high school dissection activity. The CDC says so too.
But why would I say you shouldn’t bother testing it? I love doing tests! I test the air in my home all the time.
Plus, Taobao has a bunch of formaldehyde testing machines for under 100 RMB. So why not?
“Formaldehyde detectors” on Taobao react to lots of common gases, not just formaldehyde.
These “formaldehyde detectors” actually react to a large group of gases, including harmful and harmless gases.
If you have a tester, try a little experiment: eat an orange near the tester. The detector will probably send out an alarm. Formaldehyde! You can see me doing that exact test here.
These formaldehyde detectors will react to lots of harmless things, like oranges, flowers, and peanut butter.
Last time I checked, oranges don’t have formaldehyde.
OK, so here’s your other option for testing: take air samples and send them to a lab for testing. That’s OK, but it takes a lot of time and money.
After buying a small army of testing machines, my recommendation is this: even though it sounds unscientific, our noses are pretty good detectors.
Scientists have done studies to figure out what levels of formaldehyde human noses can detect, and they found that humans can detect really low levels.
The US CDC says we should start worrying about formaldehyde at 0.1 PPM, precisely the level that most humans can start smelling it.
Bottom line: As unscientific as it sounds, our noses are quite sensitive formaldehyde detectors. Unfortunately, commercially available “formaldehyde detectors” provide no insight into formaldehyde.
3 Things You Need to Know About Formaldehyde
Thomas is an Associate Professor of Behavior Science at the University of Chicago Booth School of Business and the founder of, a social enterprise to help people in China breathe clean air without shelling out thousands of dollars for expensive purifiers.