TECHNICAL STANDARD
NACE WJ-2 / SSPC-SP WJ-2
Waterjet Cleaning of Metals — Very Thorough Cleaning
AMPP / NACE / SSPC
2021
Current
WHAT DOES THIS STANDARD COVER?
Defines the WJ-2 degree of surface cleanliness for coated or uncoated metallic substrates prepared by waterjet cleaning.
WHY IS IT RELEVANT?
Relevant where very thorough waterjet cleaning is specified but a WJ-1 clean-to-bare-substrate condition is not required. Do not reproduce detailed visual acceptance requirements.
KEY INSPECTION CONSIDERATIONS
The standard addresses a very thorough degree of waterjet cleaning of metallic surfaces. The resulting condition differs from WJ-1 and should be assessed against the specific waterjet-cleaning grade required by the project. Flash rust, retained material and the condition of the underlying surface can be important inspection considerations.
WHAT THE STANDARD SHOULD NOT BE USED TO ASSUME
WJ-2 should not be treated as equivalent to WJ-1. Waterjet-cleaning grades should not be converted directly into dry abrasive blast-cleaning grades. Waterjetting does not necessarily create a new surface profile, and visual assessment does not independently establish the absence of non-visible contamination.
PRACTICAL INSPECTION APPLICATION
Inspectors can assess the prepared surface against the specified waterjet-cleaning condition and record relevant flash rust or retained material. Existing surface profile and other specified surface characteristics should be considered separately. Additional contamination testing should be carried out where required by the project or coating system.
RELATED TECHNICAL STANDARDS
RELATED TECHNICAL TOPICS
Waterjetting; Surface preparation; Maintenance
RELATED PIL GUIDANCE
A pre-condition coating survey brings visual inspection, testing, sampling and access planning together to support evidence-based maintenance decisions.
A structured approach to investigating protective coating failure through evidence, testing, sampling and project-record review.
RELATED EXPERTISE
Coating Inspection; Condition Surveys; Technical Consultancy
ABOUT THIS TECHNICAL SUMMARY
Paint Inspection Ltd provides this information to help inspectors, engineers, asset owners and contractors understand the practical relevance of commonly referenced protective coatings standards. This page is PIL technical guidance and does not reproduce or replace the published standard. Users should refer to the current published standard, project specification, coating manufacturer requirements and other applicable contract documents when establishing project requirements or acceptance criteria.
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OFFICIAL STANDARD
PIL technical summaries are intended to explain the inspection relevance of industry standards and do not replace the published document.
STATUS AND SOURCE VERIFICATION
Official AMPP catalogue reference URL recorded in the PIL Standards Library. CMS designation, title and edition are retained from the existing controlled record. Current publisher edition/status was not independently re-confirmed during the 2026-09-23 source-verification exercise and remains subject to future PIL review against the official AMPP catalogue.