I was involved in the TETRA campaign with the Residents' Association. There are, or were, scare stories about TETRA handsets relating to the frequency of the burst nature of their emissions. When I learned that, in order to operate efficiently, the base stations operate on a steady level of transmitter power filling empty time with garbage and do not exhibit bursts in their emissions, I was convinced that even if there was some (unproven) problem with handsets, it would not apply to base stations.

The TETRA system drastically reduced the power of transmissions compared to the earlier analogue systems. I don't have the figures to hand but I seem to recall that they would be around one hundredth of the previous intensity. Unless you are within a metre or two of the transmitter (which you can't be unless you climb the mast) any transmissions from the site will be totally drowned out by Crystal Palace which has an emitter power of around 1 MegaWatt. Much more likely that this will have an adverse effect on local residents than the TETRA base station - but I've never heard of any concerns.

Parents should probably be much more concerned about their children's use of mobile phones (with aerials millimetres from their immature brains) than from transmitters 50 metres or more distant.