Historical review of development of barrier protection systems for preserved wooden poles

Barrier protection systems (BPS) prevent poles rotting in soil. Their ability to reduce grid maintenance costs of electricity distribution poles is proven, while they also conserve forest resources and prevent soil pollution by preservatives otherwise leached from the poles. Furthermore, BPS permit reduced preservative loadings in poles and all these advantages in times of rising oil prices and power outages caused the American Wood Protection Association to introduce new pole standards recognising BPS. At this time, however, the origins and development of BPS have never been comprehensively described; therefore, the purpose of this review is to provide that clarity and explain the function of the system for readers not specialised in the microbiology of pole decay.