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mW safety question

Indrabodhi

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Howdy. I'm a noob with a 5mW 405nm and some OD 6 safety goggles, and right now just viewing the dot on a non-reflective surface about 10 feet from my face feels dangerous, like my eyeballs are going to melt.

However on youtube I see people using lasers with ridiculous power levels, such as this thing
and they're seemingly fine somehow. How the hell is a man using this thing? Does he have some 500 dollar safety goggles on? A welding mask?

Is there another factor I'm missing here that determines how dangerous a laser is? I don't want to accidentally hurt myself or anyone when working with higher wattage one day.

Thank you for any and all answers provided.
 



Unown (WILD)

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Where are you people coming from? We get new members making the dumbest threads in hordes. It's crazy
 

Encap

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1-5 mw are safe to point at eye idk about spot on wal
WRONG--Dangerous misinformation by person that has no idea of what it is talking about.
If you listen to the above post #4 then "cheeseisyoureyes" .

EYE INJURY HAZARD -- DIRECT AND REFLECTED BEAM 0.99mW
Class 2 visible-light lasers are considered safe for unintentional eye exposure, because a person will normally turn away or blink to avoid the bright light. Do NOT deliberately stare into the beam -- this can cause injury to the retina in the back of the eye.
Be aware of beam reflections off glass and shiny surfaces. Depending on the surface, the reflected beam could be about as strong and as focused as a direct beam.
The Nominal Ocular Hazard Distance (NOHD) for the most powerful Class 2 laser (0.99 mW) with a tight beam (0.5 milliradian divergence) is 46 ft (14 m).
From: https://www.lasersafetyfacts.com/2/

"EYE INJURY HAZARD -- DIRECT AND REFLECTED BEAM 4.99mW
Class 3R visible-light lasers are considered safe for unintentional eye exposure, because a person will normally turn away or blink to avoid the bright light. Do NOT deliberately look into or stare into the beam -- this can cause injury to the retina in the back of the eye.
Be aware of beam reflections off glass and shiny surfaces. Depending on the surface, the reflected beam could be about as strong and as focused as a direct beam.
The Nominal Ocular Hazard Distance (NOHD) for the most powerful Class 3R visible-beam laser (4.99 mW) with a tight beam (0.5 milliradian divergence) is 104 ft (32 m)."
From:: https://www.lasersafetyfacts.com/3R/

See Laser Hazard Chart here: https://www.lasersafetyfacts.com/resources/FAA---visible-laser-hazard-calcs-for-LSF-v02.png
 
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CurtisOliver

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1-5 mw are safe to point at eye idk about spot on wall

At no point should you point a laser of any power at your eye. Even if they are considered 'eye-safe'. All this means is that the stable output isn't considered to exceed the power density required for permanent damage to occur. It only takes a sudden fluctuation of power to exceed safety levels. Also, very bad advice considering so many lasers on the market are at a false power rating and often dangerously exceeds 5mW. It should be noted Class II and IIIR rating take into consideration the blink reflex. It doesn't take into consideration someone deliberately exposing their eyes to the power levels the class covers.
 
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Indrabodhi

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Maybe your safety goggles are not for that wavelength.
I'm using this pair right here that's specifically designed for usage with blue lasers
amazon (dot) com/190nm-550nm-800nm-1100nm-Wavelength-Professional-Glasses/dp/B07DC6D11R/

After all the research I've done it seems most people consider <5mW safe for casual purposes. So I'm thinking that my laser is actually stronger than the seller (ebay) claimed it to be. Here's a picture from me testing it with a 70% battery charge.laser.jpg
 

Gatrezal

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I'm using this pair right here that's specifically designed for usage with blue lasers
amazon (dot) com/190nm-550nm-800nm-1100nm-Wavelength-Professional-Glasses/dp/B07DC6D11R/
I have basically the same ones (the blue frames/style) and I can’t see anything (through the lens) between 405-532nm with them on. There was bleed in from the edges, but I put some electrical tape (flap) there so it “seals” better for me.
 

CurtisOliver

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I'm using this pair right here that's specifically designed for usage with blue lasers
amazon (dot) com/190nm-550nm-800nm-1100nm-Wavelength-Professional-Glasses/dp/B07DC6D11R/

After all the research I've done it seems most people consider <5mW safe for casual purposes. So I'm thinking that my laser is actually stronger than the seller (ebay) claimed it to be. Here's a picture from me testing it with a 70% battery charge.View attachment 71242
That looks more than 5mW. eBay sellers regularly lie, just one of the examples for what I said above.
 

Encap

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The only way to determine the actual output of you laser is for it to be metered with an accurate Laser Power Meter (LPM).

All of the listings by eBay resellers say 5mW if you notice because eBay will remove them if they say a higher output as >5mW is a violation of US laser law. They ship using false Customs declarations, and flood the market with them from China as it is impossible to police them there. Is about the scramble for $s by unscrupulous Chinese resellers who couln't care less about legal ot safety considerations, generally.
In USA, FDA Laws, rules, and regulations prohibit importation and sale of pointers >5Mw.
"Laser products promoted for pointing and demonstration purposes are limited to hazard Class IIIa by FDA regulation.
21 CFR 1040.11(b) and 1040.11(c), limit surveying, leveling, and alignment, and demonstration laser products to Class IIIa. This means that pointers are limited to 5 milliwatts output power in the visible wavelength range from 400 to 710 nanometers."
from: https://www.fda.gov/radiation-emitt...rtant-information-laser-pointer-manufacturers

Typically, the low cost and quality $5 to $15 mass produced laser pointers on eBay output between 50mW and 100mW.

If you want excellent quality in house made or low cost but metered output mass produced pointers see: https://www.sanwulasers.com/ and also see professional level high quality hand held lasers at: https://www.jetlasers.org/index.php
 
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CurtisOliver

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It should be noted that violet appears dimmer to our eyes and that the actual power may be masked. I have seen metered eBay 405’s before now go as high as 150-200mW. As Encap stated the only way to be sure is with a calibrated lpm. However it isn’t necessary as you can be safe in presuming Class IIIb status. So not an ‘eye safe’ laser.
 

Wakrah

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405 nm isn't a wavelength I want to look at, even 10 feet away, it is worse than 450 nm blue which is so high energy, it can bleach the retina in your eye causing long term damage. 405 nm has even more energy!
 

Indrabodhi

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Thank you for the input everyone. It struck me as odd that everyone said 5mW lasers are harmless yet I used mine to clean wasps off the side of my house. It makes sense that it was falsely labelled and is far stronger.
 




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