Why is my Chemical Product Now Classified as Corrosive to Metals?

By: Joe McCarthy, Laboratory Services Manager,  email

GHS regulations have changed the way we classify materials and some manufacturers are surprised to learn that their products are now classified as Corrosive to Metals.  Historically the Hazard Materials Regulations (49CFR173), Transportation of Dangerous Goods Regulations, and WHMIS cited test method ASTM G31/NACE TM0169 immersion test to evaluate a mixture for corrosion to aluminum and steel.

With the recent updates to the HMR, TDGR, HCS 2012, and WHMIS 2015 the test method now cited is the UN TDG Recommendations Method C.1 for corrosion to metals.

A key difference between the UN TDG method and the old method is the requirement to evaluate the mixture with metal test coupons partially immersed and in the vapor phase in addition to the traditional fully immersed sample.

This picture shows three stainless coupons on the left and three aluminum coupons on the right. The two middle coupons in each group were only partially immersed.  This chemical compound was not corrosive to the fully immersed coupon (far right) but is now classified as corrosive because of the partially immersed coupon.

Are you still sure your product is not corrosive to metals?

Your product did not change, the Regulations did.

Contact:
Dell Tech
Joe McCarthy, Senior Regulatory Affairs Specialist
jmccarthy@delltech.com
519-858-5024


Dell Tech has provided professional, confidential consulting services to the chemical specialty

industry in Canada, the USA, Europe, and Asia for the last 40 years.

Contact us today for more information.

 

www.delltech.com

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