These Formaldehyde short-term gas detection tubes from Drager have a measurement range of 0.2 to 5 ppm (0.2/a).  Other substances detected included

Acetaldehyde, Buten-2-al, n-Butyraldehyde, Crontonaldehyde, 1,3-Dioxolan, Formaldehyde, Furfural and Vinyl Acetate.