[TheForge] Cheap Autodarkening Welding Helmet.

Sun Aug 10 15:12:03 2003

A place like "Pearl Eye Tech" that makes glasses can test for UV blocking.
They do it for the UV coating on glasses.
Darrell

http://www.machinemaster.com
----- Original Message -----
From: <[email protected]>
To: <[email protected]>
Sent: Saturday, August 09, 2003 5:11 PM
Subject: Re: [TheForge] Cheap Autodarkening Welding Helmet.

> I had heard that before.  What I am curious about is how can you tell
> that it is in fact blocking the UV?   I generally don't trust cheap
> tools from Harbor Freight(or elswhere)  and generally inspect and test
> them to the debree that I can on the odd occassion that I buy any these
> days.  So how does one test the UV permeability of a lens?  I can tell
> it is stopping the visible spectrum alright, but outside of that is
> there an easy way of verifying?   Regarding the sensitivity of the auto
> feature, it had two switches that adjusted sensitivity (high and low)
> and speed ( fast and slow).   I used it in the high/fast setting as the
> other settings were nothing like my sellstrom that I have gotten used
> to.   On the high sensitivity setting it tends to darken even on
> sunlight reflected off the bare metal, but I would rather that than the
> alternative.
>
> Charles
>
> Darrell wrote:
>
> >It is not the speed of darkening that blocks the UV rays, nor the shade
that
> >it darkens to. The material that the lens is made from is what blocks the
> >UV. Even if the lens failed to darken, your eyes are protected from the
> >harmful rays.
> >Darrell
> >
> >
>
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