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a coating specification, using an elevated water storage tank as an example. PRINCIPLE No. 1 — Know the environment in both the location where the tank will be painted and the environment in which the tank will serve. Water tanks can be pre-fabricated, pre-painted, then installed on a different site from the fabrication site, then touched up after the final installation; or they can be pre-cut steel sections welded on the site where they are painted with both the internal linings and exterior protec- tive coatings. Writing a complete surface preparation and application specification for each of these is dramatically different. Simply copying an old specification that worked well in one site, such as Alaska, and changing the description for a tank that will be painted and serve in a location near the Equator is a recipe for failure. The exact same coatings and linings can perform vastly differently in a typically cold environment than in a constantly hot, humid environment. PRINCIPLE No. 2 — Know the governmental regulations for worker safety and health, as well as the environmental regulations affecting the choice of coatings in the area where the tank will serve. For example, vinyl coatings have excel- lent long life case histories in both interior linings and exterior protective coating of water tanks. They are no longer available in the USA and Canada since they do not meet the VOC restrictions of either country. However, vinyl coatings are still readily available in Central and South America, as well as many countries in the Middle East, Asia, and Southeast Asia. Fu r t he rmor e, ev en wi t h VOC-compliant coatings, the require- ments for worker protection and safety can widely vary. The contractor has to know what those costs will be before he submits a bid for the job. Any uncer- tainty on his part wi ll surely cause him to increase his bid to cover the unexpected costs. PRINCIPLE No. 3 — Know what the owner expects. That sounds simple enough, but the fact is that many a coating specif ica- tion is writ ten without a discussion with the owner to determine what he really wants from that tank. Usually the interior lining requirement involves a desire for protection of the purity of the potable water but, in addition to linings, it may also require cathodic protection (CP). Unless the specifier truly under- stands what the owner wants in that location, he could create a failure by Write in Reader Inquiry #34 January 2009 J www.coatingspromag.com 29