led & eye safety

[R.Lewis]

EN60825-1 is a bit of a quagmire (to me anyway).

For a class1 device I believe that no label is required to be fixed to the
product but in the instructions and/or manual there should (must?) be a
reference to it being class 1.

Is this correct?

Does this mean that, say, a simple torch (with a 1W incandescent lamp - way
way below the limits of class1) needs to be referred to as class 1 in its
instructions?
What if there are no instructions?
Must there be some just for somewhere to write class 1 ?

 

[John Larkin]

EN60825-1 is a bit of a quagmire (to me anyway).

For a class1 device I believe that no label is required to be fixed to the
product but in the instructions and/or manual there should (must?) be a
reference to it being class 1.

Is this correct?

Does this mean that, say, a simple torch (with a 1W incandescent lamp - way
way below the limits of class1) needs to be referred to as class 1 in its
instructions?
What if there are no instructions?
Must there be some just for somewhere to write class 1 ?

What about a candle?

John

 

[[email protected]]

The class definition is for lasers. LED sources are generally safe
because they can be shut off in time by the blink reflex. An exception
is for radiation outside the visual bandwidth.

 

[Bob May]

It is the power density that is the thing that is important. A laser has a
very high power density as the beam is not spread out like a LED or
incadesent source is.

 

[John Woodgate]

It is the power density that is the thing that is important. A laser has a
very high power density as the beam is not spread out like a LED or
incadesent source is.

I'm not sure that there isn't, but basically the temperatures in the
upper atmosphere are not right.

 

[[email protected]]

I answered this ozone problem previously.

It is the unstable wind patterns in the northern hemisphere due to the
assymetrical land masses that clears away any stable layers required
for an ozone hole to persist. However, if polutants continue to
increase, a semi stable hole will appear in the north. There is
already some evidence of this.

 

[Keith Williams]

I answered this ozone problem previously.

It is the unstable wind patterns in the northern hemisphere due to the
assymetrical land masses that clears away any stable layers required
for an ozone hole to persist. However, if polutants continue to
increase, a semi stable hole will appear in the north. There is
already some evidence of this.

Which appears to be ol' Sol playing tricks rather than hairspray.
Better get him to clean up his act!

http://www.livescience.com/forcesofnature/050301_ozone_thinning.html

 

[R.Lewis]

The class definition is for lasers. LED sources are generally safe
because they can be shut off in time by the blink reflex. An exception
is for radiation outside the visual bandwidth.

No.
The class definition is for lasers *and* leds.

(note that 608325 is not for incandescent lamps so please read '1 lumen led'
for '1W incandescent lamp' in my original post.)

 

[Spehro Pefhany]

Which appears to be ol' Sol playing tricks rather than hairspray.
Better get him to clean up his act!

http://www.livescience.com/forcesofnature/050301_ozone_thinning.html

And here are some claims (published in New Scientist) that
hydroelectric power can more greenhouse gases than burning fossil
fuels.

http://www.newscientist.com/article.ns?id=dn7046


Best regards,
Spehro Pefhany

 

[Rich Grise]

I'm not sure that there isn't, but basically the temperatures in the
upper atmosphere are not right.

The Earth's north and south magnetic poles attract opposite polarities
of solar wind particles, so the auroras (which are actually the culprits)
work differently in the North and South.

And the other thing is, that whole ozone hysteria is a crock of
propaganda.

Cheers!
Rich

 

[Clive Mitchell]

And the other thing is, that whole ozone hysteria is a crock of
propaganda.

If you really think there's a shortage of ozone, then my website has a
few details on making some more using nothing more than an old neon
transformer, some stainless steel fly screen and a bit of glass out of a
cheap picture frame. Of course, how you get the ozone up there once
you've made it is up to you.

 

[Chris Carlen]

What about a candle?

John

The sun should simply be banned!



--
_______________________________________________________________________
Christopher R. Carlen
Principal Laser/Optical Technologist
Sandia National Laboratories CA USA
[email protected]
NOTE, delete texts: "RemoveThis" and "BOGUS" from email address to reply.

 

[Spehro Pefhany]

The sun should simply be banned!

That's what Ray-Bans are for!


Best regards,
Spehro Pefhany

 

[Don Klipstein]

EN60825-1 is a bit of a quagmire (to me anyway).

For a class1 device I believe that no label is required to be fixed to the
product but in the instructions and/or manual there should (must?) be a
reference to it being class 1.

Is this correct?

Does this mean that, say, a simple torch (with a 1W incandescent lamp - way
way below the limits of class1) needs to be referred to as class 1 in its
instructions?
What if there are no instructions?
Must there be some just for somewhere to write class 1 ?

Many incandescent lamps exceed Class 1 (.4 microwatt in the
400-1500 nm band being able to enter a pupil 7 mm wide and be focused onto
a spot on the retina of angular size smaller than .0002 steradian will
exceed Class I if I correctly read and understand 21 CFR 1040.1)

In the USA, the regulation by the Center for Devices and Radiological
Health that defines these classes does not have regulatory force on light
sources other than lasers, including not on incandescent lamps nor LEDs
if I understand correctly. In addition, Class 1 does not require a label
even for lasers if I read and understood 21 CFR 1040.1 correctly.

- Don Klipstein ([email protected])

 

[John Woodgate]

I read in sci.electronics.design that Clive Mitchell

If you really think there's a shortage of ozone, then my website has a
few details on making some more using nothing more than an old neon
transformer, some stainless steel fly screen and a bit of glass out of a
cheap picture frame. Of course, how you get the ozone up there once
you've made it is up to you.

Just make He6O3; the helium will make it float up to the stratosphere,
where it will conveniently decompose.

 

[Keith Williams]

I read in sci.electronics.design that Clive Mitchell

Just make He6O3; the helium will make it float up to the stratosphere,
where it will conveniently decompose.

Hmm, He6O3 has a molecular weight of 72. Me thinks this idea won't
float.

 

[John Woodgate]

I read in sci.electronics.design that Keith Williams <[email protected]>

Hmm, He6O3 has a molecular weight of 72. Me thinks this idea won't
float.

But it has anomalously low density, due to the huge size of the
molecules.

 

[danek]

In any safety document you have to watch your shoulds and shalls.
"Shall" means you must. "Should" means it is a good idea if you do
this. To quote from the 60825-1 manual section 5.2

Class 1
Each class 1 laser product SHALL have affixed an explanatory label
(figure 15) bearing the words:
CLASS 1 LASER PRODUCT
or instead, at the discretion of the manufacturer, the same statement
may be included in the information for the user.

--end quote--

To interpret this means you MUST either put a label on the device or
include the same verbiage as the label in the user manual.

60825-1 is for Lasers
60825-2 is for optical comm systems that include LEDs or lasers

Neither document covers incandescent illumination. Hazard calculations
are based on power per unit area per unit time and are wavelength
dependent. Do NOT do these calculations unless you fully understand
them. If you miscalculate in the wrong direction you could loose an eye.

Best Regards,
P. Danek

 

[keith]

The class definition is for lasers. LED sources are generally safe
because they can be shut off in time by the blink reflex. An exception
is for radiation outside the visual bandwidth.

Last time i checked, the "blink reflex" was a tad slower than LED
light.
Also, LED light travels just as fast as laser light?

 

[[email protected]]

It's not the speed of light that matters it's the illumination value on
the retina. A laser is a point source which creates a diffraction
pattern of very high illumination on the retina. An LED is an extended
source which does not.