C O N T E X T 1 2 5 : J U LY 2 0 1 2 9 Supporting Columns How to avoid killing yourself Following his reflections in our previous issue, Ian Hume draws some more lessons from his long career as a conservation structural engineer. They might just save your life. After my beginnings as a draughtsman, I moved on to become a professionally qualified structural engineer designing reinforced concrete-framed buildings such as UK embassies and high commissions, and aircraft hangers. I was involved with committees for British Standards and, following a number of serious accidents, a government committee on the adequacy of temporary works. How to access dangerous structures is an ever-present problem. Do we start at the top and work down, or start at the bottom and work up? For the initial inspection one should always start at the bottom, so that a floor can be inspected before it is walked on. One decaying country house had a stunning ballroom that immediately invited viewing. Subsequent exploration of the cellar showed the ballroom floor to be seriously rotted and dangerous. Never walk on piles of debris, as therewill be uncertainty as to the condition of the floor that is hidden beneath. Never go alone to dangerous buildings and do not put your life at risk. Ruins are perhaps best examined from hydraulic platforms and through binoculars, as there is always a risk of falling masonry and floors. It is best to avoid wet, windy or frosty weather when inspecting ruins and other very dangerous structures. Have you ever used an old fixed access ladder, only to find when you were part way up that it was quite rotten? I have. Such ladders should be inspected before use – often a difficult chicken-and-egg problem, as decayed areas might well be part way up. Having reached the top of a long ladder accessing a church dome in Delhi, I was alarmed to discover serious rot. Have you ever been to a building and discovered that you need a ladder to get into the loft, but while you do not have a ladder there is an old dining room chair of suitable size? Do wait until you have proper access equipment. I have never yet fallen through an old chair but there is always a first time. Steeplejacks’ ladders present an interesting challenge. They are not for the fainthearted, so do not be tempted to use them unless you feel really confident. Half way up the first one I used, fixed to a 70 metre chimney in Belper, I met someone coming down. The best way to inspect things like factory chimneys or spires is to get the steeplejack to take a detailed video of the problem. You can then carry out your inspection from the comfort of your living room. It is not quite the same hands-on experience, but it is rather safer. Like so many aspects of life, one thing bears on another. So it is with my early experience with temporary works relating to later work with historic buildings. I long ago concluded that it is often quite easy to decide how to solve an historic building problem, but that it is quite another matter to decide how it can be done safely.We need to pay particular attention to how rotted beams are to be Two sides of the same piece of timber
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