Freya BlekmanOne of the things I’m did at #cern today before travelling home is redoing my “self-rescue mask” training. Which involves these metal boxes
Being able to use these self rescue kits are an essential requirement of being able to work underground at facilities like CERN. Btw sewer workers also get to use them, supposedly!
Self-rescue masks use a chemical (potassium oxide) to convert some of the carbon dioxide and water in your breath into oxygen (for about half an hour)
The reason we need them is that in the tunnels a gas leak could potentially push away all the breathable air
If you open the metal boxes the inside looks like this - yes they come with goggles (for smoke/gas/dust protection) and a nose clip
I have been trained to use these masks for a long time, about 15 years I reckon. And every few years we all need to redo the training and pass the exam.
The exam involves being able to put the mask on correctly within 40 seconds and during a simulated emergency 🚨 (pic: fake tunnel with real but harmless smoke)
I find it extremely comforting thatthese masks are really for super extra safety - since we have been using them in the 2000s no one has been in an emergency where they were necessary (there was one false alarm but better safe than sorry)
And good news! This morning I passed my exam and successfully and correctly put on my mask in well under 40 seconds. In the coming years I am allowed to work underground again (including tours!) See pic for proof. Safety is not flattering 🤪
Carlos Guerreiro@carlos nope because it is an exam mask
@carlos the real self rescue kits we take underground are only useable for 30 minutes after activating. So we have slightly modified versions (that stay good for long =don’t do the chemical reaction) for training and exams.
@freyablekman
Now reading your previous posts and realising you'll be breathing in a closed loop with that chemical reaction. Interesting.
Now reading your previous posts and realising you'll be breathing in a closed loop with that chemical reaction. Interesting.
Christophe Delaere 
@freyablekman so there is a new design for the glasses ?
@ChristopheDelaere yeah finally