Wood preservation a long-practised method and often used in today's carpentry workshops. Technological developments mean it is also possible to spray preservative over the surface of the timber. Some of the liquid is drawn into the wood as the result of capillary action before the spray runs off or evaporates, but unless puddling occurs penetration is limited and may not be suitable for long-term weathering. By using the spray method, coal-tar creosote, oil-borne solutions and water-borne salts (to some extent) can also be applied. A thorough brush or spray treatment with coal-tar creosote can add 1 to 3 years to the lifespan
Oil sands to asphalt than to coal tar, and the term "oil sands" (or oilsands) is more commonly used by industry in the producing areas than "tar sands" because synthetic oil is manufactured from the bitumen, and due to the feeling that the terminology of "tar sands" is less politically acceptable to the public. Oil sands are now an alternative to conventional crude oil. In Canada, the First Nation peoples had used bitumen from seeps along the Athabasca and Clearwater Rivers to waterproof their birch bark canoes from early prehistoric times. The Canadian oil sands first became known to Europeans in 1719