Is there a height restriction? I would assume that you could not go up continuously but what is the cut off piont? All manufacturer's will give limits to the FREESTANDING height of the tower they provide. If you already have a tower yourself, ensure it has been regularly inspected, ensure you use the Manufactures Instruction Manual during the assembly procedure and ensure the assemblers have been trained. There will eventually be a limit as you will exceed the SWL (safe working load) of the tower. If you need to brace a mobile tower then I suppose its not mobile anymore and then is it adequate for the job in question would there be a need to erect a more permanent structure? By braced, i assume you mean tied to a suitable structure. Alloy towers can be assembled higher than the height the manufacturer recommends only IF it is tied in. I have also heard mixed views on the use of a harness on mobile towers are not neccessary? Incase the tower is pulled over ? I suppose if the tower is adequately braced due then a harness would be advisable There is no need/requirement to use a harness on a mobile tower. If the tower is 'pulled over' then you are going with it. The guardrails offer you collective prevention negating the need. If your boss insists you wear a harness, ensure it is affixed to a suitable anchor point OUTSIDE of the tower (and that opens up another can of worms re rescue plans) We need to gain access to several process valves twice yearly for maintenance purporses the heighest valves are set at 8 metres, there is no way for a cherry picker or other similar to device to get into the process hall any guidance appreciated, the main use would be for valves at a lower level than this 4-6m in height As mentioned earlier in this thread, all towers that conform with BS EN 1004:2004 would be suitable for your process. Just ensure your assemblers have received suitable training. PM me if you need anymore info.