Abrasive Blast Cleaning
Surface preparation by abrasive grit; standards Sa 1, Sa 2, Sa 2.5, Sa 3 per ISO 8501.
In practice
Surface preparation by yard staff; coating inspector certifies grade. Sa 2.5 is the typical PSPC requirement.
Regulatory detail & full definition
Surface preparation by abrasive grit propelled at high velocity against steel substrate. Quality is graded under ISO 8501-1:2007 — Sa 1 (light blast cleaning), Sa 2 (thorough), Sa 2.5 (very thorough, near-white metal), and Sa 3 (white metal). PSPC (MSC.215(82)) requires Sa 2.5 in ballast tanks of new-builds. The grade affects substrate roughness and contamination level and therefore the coating life. Inspection during application uses the ISO 8503 reference comparator and surface dust class checks; deviations require re-blasting before paint is applied.
Authoritative source: ISO 8501 (surface preparation) ↗
Related
Source: ISO 8501-1:2007
High confidence
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