Hi, this is an interesting and important thread, and I want to add my 2 cents. Please note that I am writing as a private citizen, and not in any capacity with laser organizations.
First, a note that I am not covering all parts of this topic. I am primarily concerned with what U.S. federal law states, and whether various parties are interpreting this correctly. Yes, it may be a smart idea to keep your laser inside so some cop on the beat won't arrest you because he thinks aiming a laser in the sky is illegal. But "smart ideas" or "good practice" is not my topic here.
My discussion here is about U.S. federal law (such as 21 CFR 1040.10 and 1040.11) and regulations derived directly from that law. This is different from interpretations of the law and of the regulations.
These interpretations can come from many different sources. They can come from agencies such as CDRH or FAA via printed publications. (Two examples are given below.) They can come from the agency employees, as when steve001 emailed Cory Tylka or when ElektroFreak talked to CDRH personnel. They can come from laser safety experts like Greg Makhov, who teaches courses on the subject. They can even come from people with less formal training, like myself and like many of the people posting in this thread.
INTERPRETATIONS CAN BE WRONG
A key point: Interpretations can be wrong. Don't believe everything you read, even if it comes from CDRH, or FAA, or steve001, or ElektroFreak, or even me <g>. Always go back to the original law.
For example, while the CDRH's "Important Information for Laser Manufacturers" publication says that CDRH can control lasers promoted for "amusement" purposes, that is completely 100% incorrect. The word "amusement" does not appear anywhere in 21 CFR 1040.10. (This is important because it can be argued that there is a difference between "entertainment" which CDRH can regulate under 21 CFR 1040.10, and "amusement" which they cannot regulate. I will not go into the exact differences at this time.)
To give another example, the FAA's Advisory Circular 70-1 says that outdoor laser operations "should" be reviewed by the FAA. The reason it does not say "must" is because (correctly) there is no requirement in U.S. law for the FAA to approve laser operations.
To give a third example, FDA has given indications that handheld lasers can be regulated as "surveying, leveling or alignment" (SLA) lasers. My personal view is that this is plain English wrong. I have written in great detail elsewhere why I believe this is so. If FDA were somehow to issue new regulations based on this interpretation, it would still be possible to challenge this in various ways. So it could be "law" but until issuing final rules (and maybe until a court case is brought) I feel it is correct to say that FDA's interpretation is wrong based on 21 CFR 1040.10 which is the source of their authority.
In an nutshell, just because CDRH or anybody else says "X" does not necessarily mean "X" is true. Read the applicable laws and related regulations (like CDRH's Laser Notices, which represent agency guidance that falls below Congressional acts but above information papers like "Important Information for Laser Pointer Manufacturers").
ARE LASERS OVER 5 mW ILLEGAL TO OWN OR USE?
About pointers: CDRH requires lasers called "pointers" or sold for pointing applications to be under 5 mW. A laser 5 mW or more can be legally sold under Federal law and CDRH regs as long as it meets all requirements for its laser power classification (e.g. keyswitches or equivalent on Class 4 lasers) and as long as it is not called a "pointer" or is sold for pointing applications.
If a laser 5 mW or more is illegally sold as a "pointer" or for pointing applications, the illegality is on the manufacturer or seller. It is NOT illegal under federal law to possess lasers, even handhelds, 5 mW or above. It is NOT illegal for a person to use them as long as they are used responsibly. There are three uses where FDA can regulate lasers 5 mW or more: demonstration (including laser shows); medical; and surveying, leveling or alignment. If you fall in this case, then you need a variance from CDRH. Otherwise, enjoy yourself and be safe.
Here is my understanding. (Correct me if I am wrong...) This is not like illegal guns or drugs, where a gun or drug might be legal but use or possession is illegal. This is the opposite: the person manufacturing or selling the device has done something illegal -- not you by buying or possessing it. I am not aware of any law or regulation requiring the end user to return an "illegal" laser pointer, even if it is recalled by the CDRH. (This is similar to how the owner of a recalled automobile is not required to have the repair made or face repossession by the government.)
I am not sure about the illegality of using a laser that does not have the proper safety features (like keylocks) for its class. I am pretty sure that personal possession and use is legal. However, use in a CDRH regulated context (demonstrations, medical, SLA) would definitely not be allowed.
CAN YOU WAVE LASERS IN THE SKY?
Can you go in your backyard and wave a laser around in the sky? The short answer is "yes, if it is for personal use and is not aimed at an aircraft." In fact, the laser can leave your property; for example, it can go above a neighbor's yard. Also, you can be on public property and aim into the sky.
(Use common sense. If you are in an airport parking lot, it is not a smart idea even if you are 100% sure there are no aircraft near your beam. But that does not mean it is illegal under Federal law.)
Earlier in this thread, steve001 quoted Cory Tylka of the CDRH as saying "Shining a laser or high powered light into the sky is not, in itself, illegal, and amateur astronomers have been using lasers safely for quite a few years, but you may have read news articles about people being arrested and charged for illuminating aircraft." Cory is entirely correct, based on my reading of the applicable laws governing lasers and governing FAA control of airspace.
A bill currently before Congress states you cannot aim at an aircraft or its "flight path". There is no definition of this term in the law. So if the law passes, you'll be on your own as to how far your beam needs to be from an aircraft so that it is away from its flight path.
IF AN AIRCRAFT SEES YOUR BEAM IN THE SKY, CAN YOU BE PROSECUTED?
Commercial and civil pilots in the U.S. are required to report any lasers that they see to the FAA. This requirement does not make a distinction between lasers that are off in the distance or clearly are not targeting the aircraft, and lasers that are aimed at or near an aircraft.
So it is possible that a person aiming a beam into empty sky could be tracked down and interviewed or arrested, even if the beam was not aimed towards a plane or its direct flight path. That does not make it "illegal", it just means that a court would have to decide if seeing the laser beam was interference enough to fall under the various statutes that could apply.
Said another way, aiming a beam into the sky in and of itself is not illegal.
IF THE LASER IS UNDER 5 mW, CAN I WAVE MY LASER WHEREVER I WANT?
No.
The power of the laser does not matter. At least one person has gone to jail for aiming a 3 mW laser at an aircraft. Also, the power density (irradiance) of the laser at the aircraft does not matter. The person on the ground is not expected to know the irradiance, and whether it exceeds the laser safety airspace (SFZ, CFZ, LFFZ) limits of where the aircraft is.
Laws are written so that hitting an aircraft, or even aiming at it, are considered illegal regardless of the irradiance. (Here I am talking about state & local statutes in addition to federal laws and FAA's civil penalties announced earlier this year.) That means that there is no legal distinction between aiming a laser less than 5 mW into the sky, and aiming a laser 5 mW or more.
CAN I DO A BACKYARD LASER SHOW IF I AM THE ONLY VIEWER?
A question was asked about a scenario where you fire up a laser projector in your backyard to enjoy the beams, and a scenario where you do the same thing but you invite people on Craigslist and charge them $15 to view the show.
My understanding is the second is illegal. CDRH can regulate products "introduced into commerce". They also can regulate three uses -- demo, medical, SLA -- if introduced into commerce. The backyard show is a "demonstration laser product" under CDRH regulations (and historic use); by charging money the show/product has been "introduced into commerce" and thus becomes subject to their jurisdiction.
I am sure there are some edge cases such as what happens if you invite dozens or hundreds of people, but you don't charge anything. I am not going to get into fine distinctions. For now, if you and your friends/family are watching a show in a home or similar private gathering (such as your hotel room while on vacation), I don't believe there is anything in 21 CFR 1040.10 or 1040.11 giving CDRH legal jurisdiction.
I am not fully up on how the laser's power enters into this. For lasers less than 5 mW, I believe that if the laser meets all requirements such as a laser product report filed and having all safety features for its Class, then the CDRH does not have jurisdiction over its use (e.g., a variance is not needed even for demonstrations or laser shows).
One reason I am hesitant to be certain about this, is because I'm unclear whether lasers under 5 mW can be used completely regulation-free*. I have asked CDRH "Can I use lasers under 5 mW for audience scanning"? I've gotten conflicting answers: "No, you can't scan no matter what" and "Yes, its OK because it is less than 5 mW." So if you want to do this, it would be a good idea to ask someone at CDRH first and "get it in writing."
(*By "regulation-free" I mean CDRH regulations, not any additional laws against assaulting people or harming their eyes. The subject of audience scanning safety, and under what conditions it might cause harm, is too complex to get into here.)
SUMMARY
I saw a number of incorrect or incomplete answers during this thread, so that's why I'm writing. Sorry for the length; it is a complex topic to explain.
At the website LaserPointerSafety.com, there are pages with additional details and explanations on many of these topics. Most are in the "Perspectives & opinions" section and the "Laser pointer laws" section. If you find anything incorrect or have suggestions for improvement, feel free to write to me personally.
I am glad to see this topic discussed. I hope that in the future, the essential basics will be correctly understood -- such as the fact that it is legal to point lasers into the sky as long as they are not aimed at or near aircraft -- and any disagreements will be over finer points and edge cases.
Thanks for reading this,
-- Patrick Murphy, a private citizen who is not representing any organization
