Formaldehyde is invisible and the exposure is cumulative — so measure your actual week, not one moment from a handheld meter. Leave the badge out for a day or for seven, then post it back.
Formaldehyde off-gasses from pressed-wood furniture, cabinetry, laminate flooring, new carpet and some insulation — often for months or years after installation. It's invisible and has no useful odour threshold at the levels that matter.
It's also strongly temperature- and humidity-dependent: the same house can read very differently in August than in February, which is why a measurement over a real week beats a spot reading. Newer construction, recently renovated homes and manufactured housing tend to read highest — exactly the situations where someone has just moved in.
This is the one badge in the line that comfortably supports a week-long deployment, because DNPH chemistry chemically bonds each aldehyde as it arrives — nothing diffuses back out. Open the sealed pouch, write down the exact start time, and place the badge at breathing height (3–5 ft), in the middle of the room, away from vents, windows, purifiers and direct sun. Nothing draped over it.
Leave it 24 hours to 7 days while living normally — longer is genuinely better here. Seal it back in the pouch, record the end time, and post it the same day. Return within 14 days of use.
The badge contains a medium coated with DNPH (2,4-dinitrophenylhydrazine). Aldehydes diffusing in react immediately, forming a stable hydrazone derivative — chemisorption rather than physical adsorption, which is why the badge holds its sample so well over long periods.
At the laboratory the derivatives are extracted and separated by high-performance liquid chromatography with UV detection. Each carbonyl has its own derivative and retention time, so formaldehyde and acetaldehyde are reported separately. Because the uptake rate is known, the mass recovered converts into a time-weighted average concentration over the period you recorded.
Independently operated, with no ties to filter, purifier or remediation companies. Every badge is analyzed by an accredited laboratory under a named, validated method, with a documented chain of custody — and your data is yours.
Order today, expose the badge at home, and mail it back in the prepaid mailer.
For informational & screening purposes. This is a laboratory analysis of the air sampled — not a medical diagnosis.