Bert
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Mood: " I think we are all going to die. I think that love is an illusion. We are flawed, my darling".
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Blast shields for EM chemistry labs: Design and Use
I have some experience in blast shield design for industrial pressing operations, such as rockets or flares where a composition is consolidated into a
tube with hydraulic pressure.
Typical installation is a dedicated fixture for a particular press or other type of machine, sometimes hinged/rotating in and out of position. For
factory use, a disconnect switch to prevent machine operation with the guard out of place would be advised.
I'm researching this in regards to setting up an experimental EM chemistry lab. Rather a different type of use, as equipment setup and manipulation of
equipment and materials would be highly varied.
I find plenty of information on when employers/schools/government agencies suggest or require USE of a blast shield- But little on construction
parameters, material choices and the nuts & bolts of fabrication.
https://cdn.auckland.ac.nz/assets/chemistry/for/current-stud...
On searching sciencemadness.org, I found plenty of suggestions on when a shield should be USED- And some information on home lab improvisation (that
might leave a little to be desired?)
Although using tempered glass is a good start- A laminated shield with alternating layers of polycarbonate and acrylic plastic, with a tempered glass
face on the side towards the potential explosion (protecting plastic components from scratches, melting and solvent mars or embrittlement) really
seems wiser to me!
https://www.sciencemadness.org/whisper/viewthread.php?tid=23...
Could any with hands on experience working with this type of protective equipment speak to the design parameters, point to any known government or
industry standards?
And most particularly!
How are these are best arranged for convenience in use? Obviously, if it's a chore to emplace or work behind... Someone (who IS me) will skip the use
of this "for just one quick thing" at exactly the wrong time!
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markx
National Hazard
Posts: 645
Registered: 7-8-2003
Location: Northern kingdom
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| Quote: |
Someone (who IS me) will skip the use of this "for just one quick thing" at exactly the wrong time!
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This situation is so familiar to me....temptation to take the "easy way out" is unavoidable and escalates with the false promise of safety that tends
to build up as time passes without incidents. Hoping to cheat sloth is a lost cause, I've seen countless evidence to support the claim. In my opinion,
to enforce the use of safety equipment, the only option is to make using it the "easiest way out"...hence all the safety switches that disable
everything if the shields are not engaged etc.
As for the material I do think laminated tempered glass is a good option (tempered glass panes fused together by a tough plastic film inbetween them).
It is clear and transparent, very tough, reasonably resistant to solvents and chemicals, available as a standard option product and all the shards
stay glued to the plastic film if an incident should shatter the shield.
I do have access to the full library of EU normatives as a part of my job....I will perform a search and post any results I find in conjunction with
the topic.
Exact science is a figment of imagination.......
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markx
National Hazard
Posts: 645
Registered: 7-8-2003
Location: Northern kingdom
Member Is Offline
Mood: Very Jolly
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Unfortunately I found no standards regarding the topic of blast shield construction in the EU standards library. But nevertheless I did find a lot of
documents regarding the classification and testing methods of explosives, propellants and initiating devices for civil use:
EN 13630-1 Explosives for civil uses - Detonating cords and safety fuses - Part 1: Requirements
EN 16361-1 Explosives for civil uses - High explosives - Part 1: Requirements
EN 13857-1 Explosives for civil uses - Part 1: Terminology
EN 13938-1 Explosives for civil uses - Propellants and rocket propellants - Part 1: Requirements
EN 13763-1 Explosives for civil uses - Detonators and relays - Part 1: Requirements
These are the main standards that have many more linked to them regarding specific testing methods and equipment, assessment of results etc. There is
no point in writing down every single one of them. If you google the standard number you usually find a preview of the first pages of the document,
showing all the other linked documents. Ironically the documents are not freely available and one has to buy access to view the full document. I only
have online viewing access and can not download or copy any of the documents, but if someone has a specific question with regards to the standards
contents then you are welcome to ask and I think we can work something out.
Anyone interested in the topic can perform a search here:
http://www.evs.ee/shop
or on any other similar site for that matter.
Hope it is of some help to the fellow sciencemadness residents....
Exact science is a figment of imagination.......
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