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SSPC-SP 6/NACE No. 3 <br />January 1, 2007 <br />along with theirconcentrations maybe obtained from laboratory <br />and field tests as described in SSPC-Guide 15.15 <br />A10 RUST-BACK: Rust-back (rerusting) occurs when <br />freshly cleaned steel is exposed to moisture, contamination, <br />or a corrosive atmosphere. The time interval between blast <br />cleaning and rust-back varies greatly from one environment to <br />another. Under mild ambient conditions, if chemical contami- <br />nation (see Paragraph A9) is not present, it is best to blast <br />clean and coat a surface on the same day. Severe conditions <br />may require a more expeditious coating application to avoid <br />contamination from fallout. Chemical contamination should be <br />removed prior to coating. <br />A11 DEW POINT: Moisture condenses on any surface <br />that is colder than the dew point of the surrounding air. It is <br />therefore recommended that the temperature of the steel <br />surtace be at least 3°C (5 °F) above the dew point during dry <br />blast cleaning operations. It is advisable to visually inspect for <br />moisture and periodically check the surface temperature and <br />dew point during blast cleaning operations and to avoid the <br />application of coating over a damp surface. <br />6 - 537 <br />