Probably should have brought this up on Tech Night. But we missed the opportunity. I need to keep an active sheet of all the crazy questions always popping into my head.
So why do we need an exposure calculator? Well, this bulletin kind of sums things up nicely. You should read it before proceeding. The FCC has adopted guidelines for RF safety, and let’s face it, as the FCC and ARRL continuously lowers the bar for the path to a license, and the hardware becomes more ubiquitous and available, any new ham with virtually no experience, can get a general license and then hook up a 1,500 watt linear in their bedroom with a square loop antenna over their bed with no real practical experience to clue them in that they just converted their bedroom into a microwave oven every time they key up.
Under new FCC guidelines operating stations will now be required to calculate RF exposure limits for stations. To make this easier for amateur stations, the ARRL now provides an online RF exposure calculator. To utilize the calculator, simply enter your peak envelope power (PEP), operating mode, and duty cycle. Many modern radios can tell you how much power you are putting into your antenna system. The calculator will then give you the minimum safe distance people must be from your antenna for safe RF exposure limits. You can print out or email the results and keep them with your station just in case someone with a badge shows up at the door (not likely), but it is certainly a good exercise for any Ham to to go through to learn more about the safety aspects of our hobby. We see things like antenna efficiency, propagation, and the like all the time. Everyone is always trying to make a better antenna. When is the last time you saw someone post the RF safety information for that same antenna, of for any antenna for that matter. Check it out.
By the way, my home configuration, =< 100 watts, and running digital modes, requires a minimum safe distance of about 3.5 ft or around 1 meter.