NukeWorker Forum

News and Discussions => History & Trivia => Topic started by: wlrun3@aol.com on Oct 24, 2011, 08:10

Title: Shielding
Post by: wlrun3@aol.com on Oct 24, 2011, 08:10
 
If microwave can be shielded by apertures of the correct width on a microwave oven door why can't gamma be shielded the same way...shadow shields, clothing?

E=hf


Title: Re: Shielding
Post by: HydroDave63 on Oct 24, 2011, 10:04

If microwave can be shielded by apertures of the correct width on a microwave oven door why can't gamma be shielded the same way...shadow shields, clothing?

E=hf

What's the 1/4 wavelength of a 6 MeV gamma?  :P
Title: Re: Shielding
Post by: Starkist on Oct 25, 2011, 01:41
I'll nibble. what in gods name is a "shadow shield"? Google produces some weird stuff haha
Title: Re: Shielding
Post by: tolstoy on Oct 25, 2011, 09:10
At first glance you're comparing a relatively huge wave with relatively small energy with the opposite: relatively high energy with very, very small wavelength.
Title: Re: Shielding
Post by: surf50 on Oct 25, 2011, 10:23
A "shadow shield" is usually a temporary shielded structure installed to provide a place for the workers to get out of the "shine" while working in a high dose area, when leaving the area is impractical.
 I've seen them used in the cavity, sump, high dose valves, etc. Lead blankets, water blocks, poly blocks all work.
Title: Re: Shielding
Post by: Starkist on Oct 25, 2011, 11:12
A "shadow shield" is usually a temporary shielded structure installed to provide a place for the workers to get out of the "shine" while working in a high dose area, when leaving the area is impractical.
 I've seen them used in the cavity, sump, high dose valves, etc. Lead blankets, water blocks, poly blocks all work.

Um, just for my mental clarity, you mean those "safe-spots"  they have all over chernobyl or is it more akin to temp shielding?
Title: Re: Shielding
Post by: wlrun3@aol.com on Oct 25, 2011, 11:34

Thankyou Hydrodave and Tolstoy...radio-1 m, microwave-1 micrometer, visible-500 nanometer, gamma-1 picometer...










Title: Re: Shielding
Post by: Already Gone on Oct 25, 2011, 01:04
Um, just for my mental clarity, you mean those "safe-spots"  they have all over chernobyl or is it more akin to temp shielding?
Yes, it's like the temporary shielding that you see during outages, but it doesn't have to be temporary.  The idea is to shield an area, rather than a source. Think of a walkway near a bank of valves or heat exchangers.  Instead of piling shielding on all those valves, you just build a wall between them and the walkway.
It's more effective and takes less shielding.
Title: Re: Shielding
Post by: Starkist on Oct 27, 2011, 04:00
Yes, it's like the temporary shielding that you see during outages, but it doesn't have to be temporary.  The idea is to shield an area, rather than a source. Think of a walkway near a bank of valves or heat exchangers.  Instead of piling shielding on all those valves, you just build a wall between them and the walkway.
It's more effective and takes less shielding.

Cool, thanks. Where does the term "shadow" come from then? Kind of strange moniker for it really O.o.  Splittin hairs at this point though. :p

Title: Re: Shielding
Post by: Marlin on Oct 27, 2011, 05:15
Cool, thanks. Where does the term "shadow" come from then? Kind of strange moniker for it really O.o.  Splittin hairs at this point though. :p



It casts a shadow, yes you are splitting hairs.   :hole:   [coffee]
Title: Re: Shielding
Post by: thenukeman on Oct 27, 2011, 08:38
I was asked in a NRC class how you would shield something.  I said if it was a nukeplant I would look at what they did last time do that and verify the shielding if it was not what I needed I would throw on another lead blanket or 2.  The instructor said that is the real life real answer.