Working Safely in a Science Laboratory 2 2.3 Safety procedures
Using a Bunsen burner Bunsen burners are very useful. They burn gas (methane) to produce a safe flame. They can burn with two types of flame – orange and blue. The orange flame is the ‘safety’ flame. It is easy to see and not as hot as the blue flame. The blue flame is used for heating. It is not as easy to see and is much hotter than the orange flame.
Chimney Window
Tube
Fig. 3 A Bunsen burner burns with an orange flame when the window is closed.
Fig. 4 A Bunsen burner burns with a blue flame when the window is open to allow air in.
Lighting a Bunsen burner: 1. Attach the tube to the gas tap. 2. Make sure that the window on the Bunsen burner is closed. 3. Light a match or have a gas lighter ready. 4. Turn on the gas tap only when you are ready to light the gas. You must be standing to the side of the Bunsen burner.
5. For safety, leave the flame on orange unless you are using it to heat something. 6. To adjust the flame, open or close the window while holding the base of the Bunsen burner. You should never touch the chimney as it gets very hot. 7. If the flame goes out for any reason you must immediately turn off the gas tap.
Tidying up equipment For a science laboratory to be safe it should be tidy. For glassware to be safe it should be clean and free of cracks.
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Things to remember when tidying up equipment: Hot equipment must be left to fully cool down before you start to tidy up. At the end of an experiment all glassware should be washed. Remember: Only put glassware in water when it has cooled down. All equipment should be returned to its correct place ready for the next experiment. Chemicals must be disposed of as instructed by your teacher.
