DIN EN ISO 17226-2:2009-09

This part of ISO 17226 specifies a method for the determination of free and released formaldehyde in leathers. This method is based on colorimetric analysis. The formaldehyde content is taken to be the quantity of free-formaldehyde and formaldehyde extracted through hydrolysis contained in a water extract from the leather under standard conditions. This process is not absolutely selective for formaldehyde. Other compounds such as extracted dyes could interfere at 412 nm. When compared with ISO 17226-1, the two analytical methods should give similar trends but not necessarily the same absolute result. Therefore, in the case of dispute, ISO 17226-1 shall be used in preference.