DIN ISO 16000-3:2013-01

Formaldehyde and certain other carbonyl compounds have a high toxic potential. This part of DIN ISO 16000 is a test standard for the area of environmental protection and is intended to be used to characterize indoor air with regard to formaldehyde and higher aldehydes and ketones. The standardized measuring method is important to recognize health-related indoor pollution and may have far-reaching implications as the investigation result can have considerable consequences, for example, with regard to the need of renovation or the success of renovation. In addition to the sphere of private households, internal spaces according to this standard include offices, schools, nursery schools, hospitals, event locations (such as theatres, cinemas) as well as the cabin interiors of vehicles, amongst others. The document is directed at representatives of supervisory authorities, testing laboratories, professional associations, planning offices, the furniture industry, the paint industry, the adhesives industry, interior designers and the automotive industry. Formaldehyde is the simplest carbonyl compound, with one carbon, one oxygen and two hydrogen atoms. In its monomolecular state, it is a colourless, pungent, reactive gas. It is used in the production of urea-formaldehyde resins, adhesives, and insulating foams. Emissions from particle (chip) board and wall insulation are the major sources of formaldehyde in indoor air. This part of DIN ISO 16000 specifies a determination of formaldehyde (HCHO) and other carbonyl compounds (aldehydes and ketones) in air. The method is specific to formaldehyde but, with modification, other carbonyl compounds can be analysed. Formaldehyde or the carbonyl compounds are collected by drawing air through a cartridge containing a substrate (silica gel) coated with 2,4-dinitrophenylhydrazine (DNPH) reagent. The principle of the method is based on the specific reaction of a carbonyl group with DNPH in the presence of an acid. During the process stable derivatives (hydrazones) of lower vapour pressure are formed according to the reaction equation which can be more efficiently retained and easily analysed. The hydrazones can be separated, identified and quantified with high sensitivity after extraction during subsequent analysis utilizing high performance liquid chromatography (HPLC) with UV detection or diode array detection. The method has been tested in an exemplary manner for the following 13 aldehydes and ketones: formaldehyde, acetaldehyde, acetone, benzaldehyde, butyraldehyde, capronaldehyde, 2,5-dimethylbenzaldehyde, isovaleraldehyde, propionaldehyde, m-tolualdehyde, o-tolualdehyde, p-tolualdehyde, valeraldehyde. Other carbonyl compounds that may be emitted into air from solvents, adhesives, cosmetics, and other sources can also be determined using this part of ISO 16000. The method is suitable for determination of formaldehyde and other carbonyl compounds in the approximate concentration range 1 µg/m³ to 1 mg/mm³. The sampling method gives a time-weighted average (TWA) sample. It can be used for long-term (1 h to 24 h) or short-term (5 min to 60 min) sampling of air for formaldehyde. This standard differs from DIN ISO 16000-3:2002-08 as follows: 11.5 "Measurement plan" and clause 13 "Test report" have been added; the determination of butyraldehyde has been specified in Figure 7; the determination of crotonaldehyde has been deleted. The International Standard has been prepared by Working Group 2 "Determination of formaldehyde" of ISO/TC 146/SC 6 "Indoor air". The secretariat of SC 6 and the chairmanship are held by Germany. The responsible German committee is NA 134-04-04-01-01 AK "Planung von Innenraumluftmessungen" ("Planning of indoor air measurements").