"UNFORTUNATELY  NOT  FOR  THE  PRACTICAL  WORLD". 

I personally am fed up with having pieces of so called  "clean glassware" blow up in my face 
or start to fume while I am working on them.
Also having to go and wash out my mouth because of god knows what inside the glassware.
THE SAD PART OF THIS IS THE PERSON THAT BRINGS IN THE GLASSWARE ALWAYS SAY THEY HAVE CLEANED IT WELL?

Below are more examples from fellow glassblowers on how they also have been the victims 
of  the so called clever people that should know better.

Every person that passes through any learning establishment throughout the world 
should take a practical test in common sense first before let loose on chemicals.

Concerning dirty glassware handed in for repair I have a cast iron rule,
backed up by my Head of Department, that it will NOT be accepted unless it
is completely clean and grease free. I have two young glassblowers working
with me and my concern is for their safety.

Once I got a 1L flask with a stucked reducer from NS29/32 to NS14/23 from a nice looking woman        (It's not that I would prefer these kind of customers). I had seen right away that there were some drops of liquid inside and after asking she said, with eyes that could lie.. "It's only water :-) !!".
So I heated up the socket and found my magical power.. I removed the reducer.. easy, that no a miracle. But that I got the water to burn, looks like the solution for the worlds energy problems and I should get the next Nobel Price for that heroic act!

After asking if the flask was clean and getting a "yes it is very clean I cleaned it myself" from the student, 
I proceeded to put the flask into the flame where it exploded and from his stupidity I lost an eye.

Not long after I started glassblowing My trainer and supervisor John Murray had one of the technical staff bring down a rotary evaporator for repair. The evaporator had a broken tubing connector that supplied the coil with water. He accepted the job as a minor work and set to doing it straight away there was some fluid left in the coil so he connected it to the compressed air supply to blow it out, as the fluid sprayed out across the workshop and landed on various surfaces it began to sizzle and bubble up. John immediately jumped up and ran to the sink and put his face under the tap to rinse it as it had also been splashed with the fluid. It turns out that someone had tried to clean the coil with sulphuric acid, they had given up on it and dumped it with the acid still in it into a cupboard for some poor unsuspecting soul to find and bring down to us. Fortunately no one was hurt, but it could easily have been a different story.