They are individually designed for specific duties and applications using a computer programme based on BS4994-1973/1987 developed over a period of 40 years taking into account pressure, temperature, life cycle fatigue and all operating conditions including seismic loading.
Tests carried out in conjunction with Kingston University on 20 year old tanks to the prototype testing procedure of BS4994-1987 have shown that there is no significant loss of mechanical strength in tanks that have been in continuous service in the most arduous of conditions for over 20 years compared with newly made tanks of exactly the same design and construction.
