ahlam1399
08-28-2019, 10:51 PM
Over 65 countries have adopted the UN Globally Harmonized System of Classification and Labeling of Chemicals. There were disparities in the way various countries classified chemicals and specified safety procedures.
أكثر... (http://EzineArticles.com/9676722)
أكثر... (http://EzineArticles.com/9676722)