The purpose of this standard is to establish the test conditions to assess the fastness of dyes in textiles of any nature and in all their stages of transformation, to the action of formaldehyde vapors as they can be released in closed spaces. where the fabrics remain stored together with fabrics that have undergone wrinkle-resistant treatments. This procedure should not be applied to assess degradation of dyes during the wrinkle-resistant finishing process, based on urea-formaldehyde, or as a consequence of subsequent dyeing treatments, with formaldehyde solutions.