AMPP SP21472-2026

Standard Practice for Internal Corrosion Mitigation for Hydrotesting & Wet Lay-Up of Onshore and Offshore Pipelines, Risers & Subsea Equipment

This standard describes the AMPP recommendations for water treatment to prevent internal corrosion of pipelines, risers, and subsea equipment during hydrotesting or when the infrastructure is filled with water and there is a need to prevent corrosion and biological growth onshore and offshore; commonly referred to as wet lay-up, wet parking, or wet storage. This SP is intended to provide requirements and educate the user on the important considerations associated with these activities. The primary purposes of the hydrotest/lay-up water treatment are the mitigation of internal corrosion and the maintenance of asset integrity over the asset service life. While proper disposal of treated water can be costly, improper disposal of such water can be environmentally hazardous, and perhaps even more costly. The owner/user should recognize the overall benefits of achieving full or extended service life when planning hydrotests or wet lay-up operations. This standard is divided into information on water quality supporting the reasoning why instructions are provided, general guidance that applies to onshore and offshore hydrotesting or wet lay-up, and information that is specific to hydrotesting or wet lay-up for onshore or offshore. General guidance is to be followed in all instances, supplemented by the onshore or offshore guidance based on the specific location.