By Anne Marie Helmenstine, Ph.D.
The WHO international biohazard symbol has a trefoil with blunt ends as opposed to the sharp ends usually seen in most biohazard symbols.
Chemistry Laboratory Safety RulesHow to Use MSDSsCommon Names for Chemicals
Chemical Weapons & Warfare AgentsWhat Is the Most Poisonous Compound?Incompatible Chemical Mixtures
Chemistry 101Periodic TableWorked Chemistry Problems
Anne Marie Helmenstine, Ph.D.
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