This is a pet hate of mine and I was wondering what others think.
Firstly, some background, I've been a science teacher for nearly 20 years, before that I worked in a hospital microbiology lab so I am very aware of the need for genuine safety in the lab.
I make my students wear safety glasses if they're heating anything in an open beaker or tube, even water, or using any chemicals that are even vaguely hazardous.
However, I'm seeing a HUGE increase in safety instructions on worksheets etc prepared for schools with really SILLY safety warnings. I hate this, I think it's counter-productive. I want my students to know that if I give them a safety instruction it's because it's sensible. Stupid warnings, when they know something is safe is just like the story about the boy that cried wolf.
Here's an example from 2011.http://sites.jmu.edu/chemdemo/2011/06/14/mm-color-wheel/
In this demo suitable for younger students, all you use are cold water, M&Ms and a plastic petri dish, yet it tells them to wear safety glasses.
Do they use safety glasses to drink water or eat M&Ms outside the lab? Of course not, so they KNOW this experiment isn't hazardous in any way whatsoever, they know there is nothing to protect their eyes from.
I don't buy the argument that they should be in the habit of ALWAYS wearing them in the lab either, that's a nonsense, they should be taught to properly assess safety. I don't make them wear saftey glasses to write with pens during a theory lesson, why would I make them when they're just dissolving M&Ms in water?