I thought microwaves caused cataracts, but ADS doesn't?

[Ben321]

I just read this FAQ https://jnlwp.defense.gov/About/Frequently-Asked-Questions/Active-Denial-System-FAQs/ about the ADS (active denial system), which is a microwave crowd dispersal non-lethal weapon. It says the frequency is 95GHz. Now when you read farther down, I noticed this Q&A pair:

Q18. The Active Denial System hits you directly in the eye, will it blind you?
A18. No. We have conducted extensive studies on whether Active Denial System can affect the eyes. The studies have all shown that natural blink reflex, aversion response and head turn all protect the eyes.

Yet in all the documentation I've read about microwave systems, I've NEVER read that closing your eyes will protect them. I can't imagine that the "natural blink reflex" would protect you, and I think microwave-caused cataracts can form almost instantly due to the intense heat from microwave absorption in your eye. I can't see how there is any possibility for anything other than cataract formation if this beam hits you in the eye without some kind of microwave-blocking goggles or glasses in place.

I know that the government wants you to feel safe, like they wouldn't ever do anything to intentionally injure you, but I also know that one thing the government does is to try to avoid causing panic. Sometimes this may mean lying to the public. So I'm not sure if this "it won't blind you" claim is true, or a lie. Does anybody else here have enough experience with microwaves in the 95GHz part of the spectrum, to be able to confirm or deny the government's claim here?

[hendorog]

They state that the skin depth is 1/64 inch which is less than 0.4mm.

If that is true then I could imagine that the eyelid could protect the eye - assuming there was enough time to react after feeling the need to close them and before damage is caused.

Adverse reactions are extremely rare, temporary and consist of skin blisters. Exposure to the Active Denial System can also result in a temporary reddening of the skin. Research shows there is only a 1/10th of 1% chance of injury from Active Denial System exposure. Normal, innate, self-protect behaviors such as eye blink, head turn and aversion response all minimize the risk of injury. The energy reaches a skin depth of only about 1/64th of an inch, the equivalent of three sheets of paper. The sensation immediately ceases when the individual moves out of the beam.

[Ben321]

They state that the skin depth is 1/64 inch which is less than 0.4mm.

If that is true then I could imagine that the eyelid could protect the eye - assuming there was enough time to react after feeling the need to close them and before damage is caused.

Adverse reactions are extremely rare, temporary and consist of skin blisters. Exposure to the Active Denial System can also result in a temporary reddening of the skin. Research shows there is only a 1/10th of 1% chance of injury from Active Denial System exposure. Normal, innate, self-protect behaviors such as eye blink, head turn and aversion response all minimize the risk of injury. The energy reaches a skin depth of only about 1/64th of an inch, the equivalent of three sheets of paper. The sensation immediately ceases when the individual moves out of the beam.

Yeah, the reaction speed is what I'd worry about. It's supposed to cause pain to disperse riots. Not sure about the actual numbers here but lets say it can heat the skin to a temperature of 150degF in a 10th of a second. Wouldn't that heating be too fast to react to? And isn't heating of the eye to 150degF enough to cause cataracts?

[hendorog]

Yep - it doesn't sound good, but expert knowledge would be required to really know.

 I imagine the moisture level of the eye surface would have a big effect on the rate of temperature rise.
Which I guess varies a lot between individuals, and if so that is something they can't know.

[Mr. Scram]

Microwaving people sounds like asking for trouble, doesn't it? It also appears to me that a layer of wet clothes or something resembling human skin or even tin foil would effectively block this weapon.

[Wallace Gasiewicz]

OK guys, Let me introduce myself.
I am a board certified physician Internal Med and Peds. I have an MPH in Environmental Medicine.

I have not looked into this stuff seriously for a long time, I have been watching for studies on these GHz frequencies

I really do not think there are any good studies done on exposure to these sorts of radiation. The stuff done on "microwaves" was done at far lower frequencies. Apparently certain frequencies go through the cornea without affecting it but somehow damage the lens of the eye.

To make it brief...I do not think there is any good information on the risks of long term exposure to any of the high frequencies that are being foisted on us. Stuff like the 5G networks that are popping up and even the WiFi that we are all using.  Not to mention all the spurious frequencies generated by these transmitters. Welcome to the lab....we are the test subjects....

Wally KC9INK

[Ben321]

According to the government website an FAQ page regarding this device, tests were done with these devices, and it didn't blind anyone. I hope that's the truth.

However, I have seen public demonstrations of the device used on a group of volunteers on the news when it first came out. It did seem to have a strong deterrent effect, and it did include audio, but I don't remember hearing anybody screaming "Oh no! I'm blind! Help!". So it seems it is eye-safe if used correctly. But I'd still be a little bit worried in a realistic scenario, if there was a riot that and the police were panicking and zapping the same person or people multiple times, with not enough cool-down time between shots.

[Mr. Scram]

According to the government website an FAQ page regarding this device, tests were done with these devices, and it didn't blind anyone. I hope that's the truth.

However, I have seen public demonstrations of the device used on a group of volunteers on the news when it first came out. It did seem to have a strong deterrent effect, and it did include audio, but I don't remember hearing anybody screaming "Oh no! I'm blind! Help!". So it seems it is eye-safe if used correctly. But I'd still be a little bit worried in a realistic scenario, if there was a riot that and the police were panicking and zapping the same person or people multiple times, with not enough cool-down time between shots.

Exactly. Tests likely mean controlled conditions and willing subjects. There's no telling what will happen when the operator ups the output or repeatedly turns it on an incapacitated or intoxicated subject. People in the field aren't exactly known for their measured response.

[LaserSteve]

I personally  know someone who once volunteered.  He's not blind..

Steve

[Mr. Scram]

I personally  know someone who once volunteered.  He's not blind..

Steve

Running a red light doesn't mean you instantly die. I'm not saying this technology blinds but anecdotal examples have little value on their own.

[jonpaul]

Hello, Microwave exposure depends on power, antenne radiation pattern and gain, pulse shape, peak power, PRF, etc.  See classic radar engineering text like Skolnick, MIT radiation lab.

The cataracts were during WWII and Cold War, affected radar techniciens  and telecommunications workers very close to a high powered system, eg tower climbers.

The wifi, cell phone and other consumer exposure is nil.

The weapons use is still experimental, and is proposed as an alternative to tear gas, DM, CS, rubber bullets etc.

In a riot situation with risk of bystanders  or officers, the lesser of two evils?

Just the ramblings of an old retired EE

Jean-Paul

[frogg]

Academic literature has reasonably detailed information on the effects of mm-Wave radiation on human flesh.

https://arxiv.org/ftp/arxiv/papers/1503/1503.05944.pdf


TLDR: If you close your eyes, you will protect your eyeballs. If you don't close your eyes, cataracts are not your immediate concern, and likely not a long term one. Regardless, your epidermis won't like it. You'll never be exposed to an ADS long enough to worry about it, anyways.

Planning on being in a riot sometime soon? Or falling asleep under an active ADS system?