(Wired) Soldiers Blinded, Hospitalized by Laser 'Friendly Fire': An American soldier was blinded in one eye and three others required medical evacuation out of Iraq in a series of laser "friendly fire" incidents, the U.S. military has disclosed. These injuries are caused by the misuse of dangerous green-laser dazzlers.
Since November 2008, a single unit in Iraq "has experienced 12 green-laser incidents involving 14 soldiers and varying degrees of injury. Three soldiers required medical evacuation out of Iraq and one soldier is now blind in one eye," writes Sgt. Crystal Reidy, from the 3rd Sustainment Command (Expeditionary), or ESC.
Captain Russell Harris, a Troop Commander with 3rd ESC reports that his troops have suffered "temporary blindness, headaches and blurred vision,” as a result of laser incidents. Others describe severe, 48-hour migraines after lasing.
These types of laser injuries appear to be common when units first deploy to Iraq, and may be the result of inadequate training; soldiers may assume that the lasers are harmless and use them without due caution.
It is not clear what type of laser was involved. In 2006, the Army's Rapid Equipping Force reportedly acquired 2,000 green lasers for use at checkpoints, as a tool to warn oncoming drivers to stop. Although they are said to be safe for eyes, the unspecified lasers are also described as being fifty times the power of normal red-laser pointers. (Green light is far more effective than red for dazzling.) MSNBC noted in 2006 that troops were trained not to use the laser closer than 75 yards, as this "would cause eye damage."
Noah and David Axe reported some time ago on the Marine Corps' struggle to get laser dazzlers; one source estimated that up to fifty civilians had been killed because of the lack an effective warning device. And instead of getting the CHP laser dazzler they asked for, the Marines' top brass stepped in and sent them the GBD-III, or Green Beam made by BE Meyers.
The problem is that the GBD-III is not intended to dazzle. The makers call it "the most powerful military grade visible lasers available" to be "used for weapon aiming or marking targets for fire support." They quote a Nominal Ocular Hazard Distance (NOHD) of 1,460 meters: In other words, the GBD-III laser can potentially cause eye injuries if used on anyone up to almost a mile away. (By contrast the CHP laser dazzler has an NOHD of 45 meters.) And it's easy to see how accidents could happen with this type of laser without thorough training.
“We are all U.S. soldiers, you would never point your rifle at another soldier, don’t point your laser,” says a Sergeant in the 3rd ESC who experienced a laser incident.
Things might be about to get a lot worse. There are a number of lasers under development for the "Counter Rocket, Artillery, Mortar," or CRAM role, detonating or destroying incoming rounds before they are a threat. Unfortunately, laser light scattered off the target may cause eye damage to anyone in the area, and the Army has issued two contracts to develop technology for safer lasers. These are a "High-Power 2.1 Micron Fiber Laser" from Advalue Photonics Inc and a "Fiber-Based, Reduced Eye-Hazard Laser" from Q Peak Inc.
"To date, the solid lasers involved have employed either neodymium (Nd)- or ytterbium (Yb)-doped media.... All operate in the 1000-1100-nm wavelength region, which, because the wavelengths are invisible but are transmitted to the retina, leads to a significant operational concern about eye safety in real-world uses. Even minimal reflections from targets or debris can exceed the eye-safety limit," notes the proposal from Q Peak.
The new lasers would be "retina safe" — any eye damage would be confined to the surface of the eyeball which is far less serious and need not result in permanent blinding.
Air Force personnel have had laser eye protection for some years. It may be time to start issuing it a lot more widely. (source)