Laboratory Safety: The Teacher’s Role

Outlined below are some considerations on laboratory safety that are intended for teachers and administrators. Safety awareness must begin with the school board and each school principal; it should be supervised by the department head (when one is designated within a school), and be taught by the individual teacher.

Principals should be familiar with the guidelines for laboratory safety and provide continual supervision to ensure compliance for these guidelines. Principals need to be supportive when teachers request assistance in implementing safety procedures. Each teacher has the ultimate responsibility for enforcing laboratory safety standards. Be sure to set a proper example in the laboratory by observing the safety rules that you teach students. For example, wear goggles and protective clothing when in the laboratory, and do not work alone. Planning is essential to laboratory safety, and the planning must include what to do in emergencies, as well as how to prevent accidents.

The activities and investigations in the McGraw-Hill Ryerson Physics 12 program are designed to minimize dangers in the laboratory. Even so, there are no guarantees against accidents. Careful planning and preparation, and being aware of hazards, will help keep accidents to a minimum. Much information is available on laboratory safety from a variety of sources; for example, the STAO Safety Document includes detailed instructions on planning safe procedures and preventing accidents. However, the phrase “Be prepared!” is probably the simplest and best policy to follow. Know the rules and always be prepared for “the common violations” that often happen. Know where the emergency equipment is stored and how to use it.

Classroom/Laboratory

Practice good laboratory housekeeping and management by observing the guidelines listed below and adhering to your local regulations. Here are some basic guidelines to consider as you plan your course.

  1. Store equipment properly:
  • Clean and dry all equipment before storing it.
  • Protect electronic equipment and microscopes from dust, humidity, and extreme temperatures.
  • Label and organize equipment so that it is easily accessible.
  1. Provide adequate workspace for students to do investigations.
  2. Provide adequate room ventilation.
  3. Post safety and evacuation guidelines.
  4. Check to ensure that safety equipment is accessible and working properly. Ideally, safety equipment should include fire extinguishers, fire blankets, and eyewash stations. Often physics experiments involve pulling or pushing objects. Ensure that these paths are free of obstacles and opening doors.
  5. Provide containers to ensure safe disposal of chemicals and waste products. It is important that containers are clearly labeled to help students dispose of waste properly. Disposal methods must meet local guidelines.

First Day in the Laboratory with Students

  1. Discuss the safety symbols on page 631 of the Physics 12 student text. Ensure students are familiar with WHMIS symbols.
  2. You may want to create a safety contract for students to sign that outlines the safety rules that they need to follow.
  3. Review safe use of equipment and chemicals.
  4. Review safe use and location of safety equipment and evacuation guidelines.
  5. Discuss safe disposal of materials and laboratory clean-up policy.
  6. Discuss proper attitude for working in the laboratory.
  7. Document students’ understanding of the above points. A good way to ensure student understanding is to have them sign a safety contract like the one mentioned in point 2.
  8. Review these safety precautions with students often during the school year.

Before Each Lab Session

  1. Perform each activity yourself before assigning it to students to determine where students may have trouble or where specific safety concerns may arise.
  2. Arrange the lab in such a way that equipment, supplies, and disposal containers are clearly labelled and easily accessible.
  3. Have available only equipment and supplies needed to complete the assigned activity. This practice helps eliminate the problem of students carrying out unauthorized experiments.
  4. Review the procedure with students. Emphasize cautions within the procedure. If students have designed their own procedure, ensure that each procedure includes the appropriate safety precautions.
  5. It is important that all students know the proper procedures to follow if an accident should occur. Students should know what to do if another student or the teacher is hurt.

During the Lab Session

  1. Make sure the laboratory is clean and free of clutter.
  2. Insist that students wear goggles whenever required.
  3. Never allow students to work alone.
  4. Shield systems under pressure or a vacuum. If you are doing a demonstration, you must shield both yourself and the students.
  5. Remove broken, chipped, or cracked glassware from use immediately. Clean up any spills immediately.
  6. Make sure that all glassware that is to be heated is of a heat-treated type that will not shatter.
  7. Remind students that heated glassware looks the same as cool glassware.
  8. Prohibit eating and drinking in the lab.

After the Lab Session

  1. Make sure that all work surfaces and equipment in the laboratory are clean.
  2. Be certain that students have disposed of broken glassware and chemicals properly. Chemicals should never be disposed of down the drain or in the garbage.