Laboratory Safety Practices

Safety is number one in any chemistry program and failure to follow safe practices can cause laboratory accidents which may result in the loss of time, damage to clothing and other property, and most important, personal injury. You can anticipate and prevent situations that would lead to accidents by following suitable precautions.

Personal Protection

  • When working in the lab you must work only on authorized experiments in the presence of a teaching assistant.
  • Whenever any laboratory work is in progress you MUST wear proper eye protection and a lab coat.
  • University of Toronto policy stipulates no contact lenses can be worn while working in the laboratory.
  • Open toed shoes (sandles) are NOT to be worn in the laboratory. Shoes with no open spaces only.
  • There will be no eating, drinking or smoking permitted. You must not even bring food or drink into the laboratory.
  • Long hair, neckties and jewelry must be confined and you must cover any frilly or flared clothing with a lab coat.
  • Acts of carelessness in the laboratory will not be permitted.
  • To avoid breaking equipment or spilling chemicals, work carefully with full awareness of what you are doing at all times.
  • Always read the label on a bottle twice before using the contents.
  • Use only the quantity of reagent needed. Never return unused reagents to its original container.
  • Only when directed to do so will you mix reagents.
  • Never place chemicals directly on a balance pan. Use a weighing bottle to weigh reagents.
  • When observing the odor of a chemical, fan air over the container towards your nose. Never smell the substance directly.
  • Never taste reagents.
  • Never use ice from the ice machine in the lab as this may be contaminated.
  • Avoid handling chemicals directly with your hands but if contact happens, immediately flush the area with cool water.
  • Before inserting the rubber stoppers lubricate the end of the glass tubing or thermometer with glycerin. With a towel or gloves, protect your hands and hold the glass close to the stopper. Insert the tube slowly with a twisting motion.
  • To draw liquids into a pipette, use a bulb or pipetting device and never pipette by mouth.
  • An acid or base should be added to the water, NOT vice versa, when diluting strong acids or bases.
  • Make sure no flammable liquids or vapors are in the area before igniting a Bunsen burner.
  • Heat test tubes at the surface of the liquid. Agitate the tube. Be sure to slant its open end away from other people.
  • Avoid an open vessel in which a process is occurring as it could produce splattering.
  • Keep all reagents and equipment away from the edge of the lab bench.
  • Cracked glassware may break when stress is put on it. Dispose of any cracked glassware.

Accidents and Injuries

As soon as possible report all accidents or injuries to the Teaching Assistant. An Accident Report form may have to be completed.
Each laboratory is equipped with a First Aid Kit which contains such aids as Band-Aids and latex gloves. Wear gloves when helping with any open wound.
If an injury should occur some immediate procedures to follow are listed below:

  • Chemicals in Eyes: Flush eyes with water at eyewash for at least 15 minutes.
  • Skin Burns: Immediately place affected area under cold running tap water for 5 to 10 minutes to remove the heat or irritant.
  • Hair or Clothing Fires: To extinguish the flames use the safety shower.


Small fires are the responsibility of the teaching assistants only and NOT the students.
Turn off the burner if the burner was the cause of the fire.
To keep a fire contained in a beaker try to smother it with a watch glass or a wet paper towel.
If the fire is large or uncomfortable the Teaching Assistants will direct students to evacuate the room immediately according to the following procedures:

  • Direct students to leave the building.
  • If possible shut down all equipment in the laboratory and close all doors.
  • Activate the fire alarm in the hallway.
  • Report the fire by calling the fire department with the yellow emergency phone in the middle of the wing or report the fire to the security.

Chemical Wastes

At the beginning of each laboratory session, special instructions will be given for waste disposal. Never pour organic solvents or toxic wastes such as solutions containing chromium, mercury, or lead into a sink. Proper disposal containers will be designated.

Cleaning Responsibilities

Students are responsible for cleaning any equipment used in an experiment, tidying up their work area and returning all equipment to its proper place.
Teaching Assistants will assign additional cleaning duties, but students should also follow these practices below:

  • Before storing away, clean all equipment. Soap solution is provided at the large sinks.
  • Clean and return all special equipment to its designated area.
  • Use tap water to wash and rinse all glassware. For the final rinse use distilled water from a wash bottle.
  • To clean bench tops and spills use paper towels. Special note: neutralize acid spills with the solid sodium bicarbonate before flushing the area with water and sponging.
  • Broken glass should be swept with dust pans, brooms and brushes which are available in the area. Place broken glass in the special containers provided and labelled "Broken Glass Only".
  • Remove paper, broken glass or other debris from the sinks.