A Loran C signal is *not* the same thing as microwave radiation.
A Loran C signal is a 100Mhz signal sent out in a precisely timed pulsed sequence.
The danger was strictly based on you becoming a path to ground for the
100 megawatts of power.Because Loran C is supposed to be operating 100% of the time, any off- air time (or problems with the timing) that lasted over 1 minute was considered "bad time" and went on the station's record. 1 minute of bad-time ruined a "perfect month". (We once set a record for 7 perfect months in a row, in the days of 15KV vacuum tubes and mechanical-relay based transmitters)
I mention that stuff so as to explain "tower maintenance" and how it relates to getting near the tower.
When the tower needed maintenance, the "book" said to kill the signal to the tower, allow the tower tech to climb onto the tower, and then energize the tower again. It was perfectly OK to be *on* the tower while it was transmitting, you just didn't want to be "too close" to the tower. Typically, this shut-down, tower-mounting and power-on sequence took less than a minute, so a station didn't ruin a perfect month over a burnt out lightbulb or some other mundane tower problem.
In reality, because the tower techs knew that shutting down the transmitter might present problems, and were sensitive to the records that stations were trying to set, most were willing to "jump the tower". This was accomplished by running towards the tower and jumping onto the concrete base with the tower energized. Of course, we never "allowed" this practice, always "protesting" vehemently - usually to no avail - but the log books would always state that the tech took it upon himself to jump the tower.
I've never seen (or heard of) anyone getting hurt via this practice, but I have seen people serious injured while working on the transmitters themselves. High voltage capacitors, such as the largest ones in this picture, pack quite a punch when the grounding system fails to do its job.