Ah but you see, in reality the PAQ-4C *IS* an eyesafe laser. In fact, on page 1 of the manual, this is what it states:
"The infrared beam is considered eyesafe based on military standards. Suitable precautions must be taken to avoid overexposure to the infrared beam."
It then goes on to tell you not to stare into it, look at it through binoculars, shine it onto mirrored surfaces (that's a neat one - how exactly are you supposed to avoid doing this in MOUT?) or shine the beam into other individuals' eyes. But these rules apply to most of the IIIa and lower, non-licensed lasers FDA considers commercially
acceptable.
The FDA considers the PAQ-4C to be a Class IIIb laser - these kind of lasers generally require a license. However, Class IIIb lasers are 5-500 mW lasers. The PAQ-4C supposedly has a power output of 0.7mW, which is not even classified as a Class IIIa laser such as the Insight M6 is.
The reason the FDA considers the PAQ-4C a IIIb laser is as near as I can tell simply because it's infrared. This isn't entirely without merit - an IR laser is CERTAINLY a little more hazardous than a normal laser because you don't know when it's on, or shining directly into your eyes. A visible or audible on/off indicator goes a long ways towards negating this problem, hence FDA actually seems to be ok with low-power IR spectrum lasers that have visible or audible indicator of operation. This letter from Insight to the FDA seems to support this:
[url]http://www.fda.gov/ohrms/dockets/dailys/00/feb00/021500/var01.pdf[/url]
Given this, I'm not sure why Insight doesn't make the public happy and release a reasonably priced PAQ-4C with a visible LED indicator. It seems unlikely that the FDA could make the case that simply operating in the IR spectrum makes an otherwise Class II laser a (much more powerful) Class IIIb. For this matter, there is probably quite a commercial market out there for a _visible_ laser version of the PAQ-4C.
It's entirely possible that there's extra-legal pressure for them not to do so from government sources - the FDA has not been very clear about any of this, and almost seems not to want to be. Wow, doesn't this story sound familiar? Almost as if there are people working at the FDA who are some really Altogether Terrific Fellows ;)