DIY formaldehyde test kit (Health and safety)

I was reading up on formaldehyde and i bumped on this project.

It’s a bit out of the scope of the Maslow project itself but important enough to post here

https://publiclab.org/notes/mathew/07-10-2015/my-diy-formaldehyde-test-kit

If there are simpler or cheaper ways to test for formaldehyde then please post it here.