A chemical laboratory is a potentially dangerous environment for those who cannot interpret the warning symbols on reagent bottles. Most accidents are due to lack of basic rules, now learn how to interpret the most common warnings in chemical environments. 
Flammable: This is the symbol indicating a flammable product, when viewing it in a reagent bottle, be careful not to expose the product near open flames or in hot (smuffled) places. 
radioactivity symbol: identifies radioactive chemicals, they are dangerous in contact with the skin, to handle them requires intense care (gloves and safety overalls). 
corrosive liquid: symbol on bottles of strong acids (such as sulfuric acid, hydrochloric acid, etc.). Take care that the acid does not spill on you, skin contact will cause serious burns. 
Possibility of electric shock: The location marked with this warning is dangerous as it contains exposed electricity, if you are not careful, electric shock may be unavoidable. 
Biological risk: This symbol represents care for nature, indicates that the product in question is harmful to the environment. From awareness, it is up to us the task of respecting or not the fauna and flora. The correct thing is not to discard products that contain this symbol in the sink drain, reserve a specific collector bottle for waste and give it to those responsible for disposal.
Explosion hazard: represents the risk of the material protruding (causing an explosion). Indicates thorough care in transport and handling. 
poisonous substance: warning symbol for non-contact with the skin. It also indicates that the product can cause death if inhaled or ingested. 
Mandatory use of gloves: When working with corrosive products, such as acids, for example, the use of gloves is mandatory. This safety equipment even protects your hands from contact with hot objects and broken glass. 
Wash the hands: This symbol translates the need for hand washing during the experiment. Do not touch eyes, mouth and nose while handling chemicals.
But if all precautions were not enough to prevent an accident (burn by acid or fire), quickly look for the symbol below: 
This is the symbol of the first aid kit, all laboratories must be equipped with it, in addition to medicines, contains a fire extinguisher (in case of fire) and eyewash product (for acid splashes on the eyes).
Laboratories must contain, as in any safe environment, fire extinguishers in sufficient conditions of use for possible accidents.
By Líria Alves
Graduated in Chemistry
Brazil School Team
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Chemistry lab
Chemistry Curiosities - Chemistry - Brazil School
Source: Brazil School - https://brasilescola.uol.com.br/quimica/simbolos-seguranca-laboratorio.htm