Laboratory Safety Rules Science is a hands-on(实际操作的) laboratory class.You will be doing many lab activities which may need the use of chemicals or equipment.To make sure of a safe science classroom，we provide you with a list of rules.These rules must be followed at all times. GENERAL GUIDELINES(准则) 1.Never work alone.No student may work in the lab without a teacher present. 2.When first entering a lab，do not touch any equipment，chemicals，or other materials in the lab until you are asked to do so.

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