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CSWIP 3.1U & 3.2U

At Apex, our commercial diving teams are certified to CSWIP 3.1U and 3.2U standards, delivering expert underwater inspection services for industries such as offshore energy, marine infrastructure, and environmental management. Our highly trained divers perform precise and reliable inspections to ensure the integrity of underwater structures, enabling clients to maintain safety, compliance, and operational efficiency in challenging marine environments.

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What Are CSWIP 3.1U and 3.2U Underwater Inspections?

CSWIP 3.1U (Underwater Inspection Controller): Involves the supervision and execution of non-destructive testing (NDT) and visual inspections of underwater structures, such as pipelines, platforms, and welds. This certification ensures divers are qualified to assess structural integrity and report findings accurately.

CSWIP 3.2U (Underwater Inspection Diver): Focuses on advanced inspection techniques, including detailed NDT methods like magnetic particle inspection (MPI) and ultrasonic testing (UT), to evaluate complex underwater assets for defects or corrosion.

Our CSWIP-certified divers operate in diverse conditions, from shallow coastal waters to deep-sea environments, using advanced tools and methodologies to deliver comprehensive inspection data with minimal disruption.

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Our CSWIP 3.1U & 3.2U Inspection Services

We offer tailored underwater inspection solutions to meet your project’s specific needs, including:

  • Visual Inspections and Surveys: Detailed visual assessments of underwater structures, such as pipelines, jackets, and risers, using high-resolution cameras and real-time video feeds to identify surface defects or damage.

  • Non-Destructive Testing (NDT): Application of advanced techniques like MPI and UT to detect internal flaws, corrosion, or weld imperfections without compromising structural integrity.

  • Structural Integrity Assessments: Comprehensive evaluations of offshore platforms, subsea cables, and other marine assets to ensure compliance with industry standards and regulatory requirements.

  • Reporting and Documentation: Thorough post-inspection reports with detailed findings, photographic evidence, and recommendations, ensuring traceability and compliance with CSWIP standards.

  • Emergency Inspection Services: Rapid response for urgent inspections, such as post-storm damage assessments or unexpected structural issues, to minimize downtime and risks.

These services support sectors like oil and gas, renewable energy (e.g., wind farm foundations), port infrastructure, and marine salvage, ensuring safe and efficient project progression.

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Why Choose Apex for CSWIP 3.1U & 3.2U Inspections?

  • Certified Expertise: Our divers hold CSWIP 3.1U and 3.2U certifications, backed by extensive experience in conducting high-precision underwater inspections worldwide.

  • Advanced Technology: We utilize state-of-the-art inspection tools, including underwater cameras, MPI equipment, and ultrasonic testing devices, to deliver accurate and reliable results.

  • Uncompromising Safety Standards: Every inspection adheres to strict protocols aligned with IMCA, ISO, and local regulations, prioritizing risk mitigation and operational safety.

  • Proven Success: Apex has a strong track record of delivering CSWIP-compliant inspections for major offshore projects, enabling clients to maintain asset integrity and regulatory compliance.

If you’re planning an underwater project requiring expert inspection services, contact us today to discuss how our CSWIP 3.1U and 3.2U capabilities can ensure the safety and success of your operations.

Poole Harbour Commissioners (PHC) Pool Port Subsea Inspection at Poole Harbour Apex was engaged by the Harbour Engineer at Poole Harbour Commissioners (PHC) in Poole Port, Dorset, UK, for a comprehensive year-long project. This involved deploying our CSWIP 3.1U-certified divers to perform detailed subsea inspections across nine commercial quays, culminating in targeted remedial works on one quay wall. Drawing on our specialized commercial diving capabilities and in-house dive support vessel, we delivered precise, standards-compliant inspections and repairs, ensuring the port's infrastructure met rigorous safety and integrity requirements. For a broader overview of the engineering aspects, view the full project case study. Objectives and Challenges Poole Harbour, a vital UK commercial hub, faces ongoing threats from tidal forces, corrosion, and operational wear, necessitating expert subsea evaluations to safeguard assets and operations. The project required inspections adhering to CSWIP 3.1U standards for underwater welding and structural assessment. Primary challenges included: Navigating variable tidal conditions, depths up to several meters, and limited visibility while maintaining inspection accuracy. Conducting non-destructive testing (NDT) and visual assessments without halting port traffic or compromising diver safety. Delivering CSWIP 3.1U-level documentation, including defect identification, sizing, and reporting for informed remedial decisions. Performing high-risk remedial tasks like subsea welding and anode placement in a live marine environment, with strict adherence to health, safety, and environmental regulations. Our Approach Leveraging our team's CSWIP 3.1U certification—ensuring proficiency in underwater inspection techniques such as close visual inspection (CVI) and ultrasonic testing (UT)—we executed the project in two phases from our dedicated dive vessel. ​ Phase 1 CSWIP 3.1U-Compliant Subsea Inspections Our certified divers conducted methodical surveys of the nine quays, focusing on CSWIP 3.1U protocols for defect detection and classification: Seabed and Depth Profiling: Accurate hydrographic measurements and seabed evaluations to identify erosion, sediment issues, and berthing hazards, using calibrated tools for precise data. Structural Defect Assessment: In-depth CVI to detect cracks, corrosion pitting, weld defects, and material degradation on quay walls and supports. Component Inspections: Thorough checks of bollards, fenders, ladders, and safety gear, documenting any non-conformities per CSWIP standards. Thickness Gauging: UT readings to measure wall thicknesses, pinpointing corrosion-induced thinning with high accuracy. All inspections were recorded via high-definition underwater cameras, with real-time topside monitoring. Reports were compiled to CSWIP 3.1U specifications, featuring defect schematics, severity ratings, and remedial priorities, enabling seamless handover for Phase 2. ​ Phase 2: Remedial Diving Operations Targeting a corroded Larsen sheet pile wall Our 3.1U divers applied advanced skills for effective repairs over several months: Surface Preparation: High-pressure jetting to clear biofouling and corrosion, allowing for unobstructed CSWIP-level inspections. Post-Preparation Evaluations: Combined CVI and UT to assess damage extent, including hole sizing and weld integrity checks. Precision Repairs: Subsea welding to seal defects and reinforce structures, executed with CSWIP-certified techniques for durable results. Cathodic Protection: Installation of 416 sacrificial anodes, positioned via diver expertise to optimize corrosion prevention. Operations were supported by surface-supplied systems and constant risk assessments, minimizing environmental disturbance and ensuring compliance with diving regulations. ​ Results and Benefits  The project underscored the value of our CSWIP 3.1U diving expertise, completing on time and budget while enhancing Poole Harbour's resilience. Notable achievements: Proactive identification and classification of subsea defects across all quays, reducing risks and supporting PHC's maintenance planning. Restored integrity to the repaired quay wall, with anodes extending its lifespan and averting costly future interventions. Comprehensive, auditable reports that aligned with industry standards, facilitating regulatory compliance and stakeholder confidence. Uninterrupted port operations, highlighting our efficient, safety-focused diving practices. PHC praised our divers' technical precision and report quality, solidifying Apex as a leader in commercial diving services. This case study complements our engineering-focused project overview, demonstrating how CSWIP 3.1U skills drive superior underwater outcomes.

Jack-up Rig Collision Inspections. Case Study: CSWIP 3.1U Underwater Inspection of Jack-Up Rig Leg Damage – Portland Port, UK Executive Summary An eight-legged jack-up rig was re-routed to Portland Port, Dorset, UK, after sustaining structural damage. To support an insurance claim and determine necessary remedial works, Apex was asked to deploy a certified 3.2U commercial diver to conduct a CSWIP 3.1U underwater inspection. Background The jack-up rig, an eight-legged self-elevating mobile offshore unit, is designed for shallow-water operations. Each leg, constructed from high-strength steel, provides stability through preload mechanisms and spud cans anchored to the seabed. The rig was moored at Portland Port, a sheltered deep-water facility, awaiting redeployment to an offshore site. Following the impact the charterer commissioned an urgent CSWIP 3.1U underwater inspection to evaluate the structural condition of the affected leg section. The CSWIP 3.1U certification, administered by TWI, ensures divers are qualified for underwater visual surveys, ultrasonic testing, and close visual examination (CVE) of marine structures. The inspection aimed to quantify the damage for an insurance claim under the rig’s all-risk policy and to specify remedial works to comply with the Merchant Shipping (Accident Reporting and Investigation) Regulations 2012 and HSE offshore safety guidelines. Scope of Work The inspection scope included: •Visual and Close Visual Examination (CVE): Detailed mapping of dents, cracks, and coating damage. •Ultrasonic Thickness Measurement (UTM): Assessment of wall thickness to detect impact-related or corrosion-induced thinning. •Flooded Member Detection (FMD): Verification of watertight integrity in the leg’s internal compartments. •Cathodic Protection Assessment: Evaluation of sacrificial anodes and corrosion potential in the damaged area. •Baseline Survey: Condition assessment of adjacent legs and spud can for comparative analysis. Inspection Methodology A CSWIP 3.1U-certified diver, supervised by a Class survey inspector, operated from “Skindeeper” Apex’s dive support vessel (DSV) moored alongside the rig. Equipment included: •High-resolution underwater cameras with LED lighting for video and still imagery. •Ultrasonic flaw detectors (Cygnus) calibrated to BS EN ISO 17640 standards. Divers were deployed via surface-supplied umbilical systems, with inspections following CSWIP-DIV-7-95 protocols. Real-time data and video feeds were relayed to the DSV for analysis. Environmental monitoring ensured compliance with UK Port State Control regulations, with no hydrocarbon or hazardous material releases detected. Conclusion The CSWIP 3.1U inspection provided critical data to quantify the damaged Leg, enabling a robust insurance claim and facilitating rapid remedial works to restore the rig’s operational readiness. Conducted in the controlled environment of Portland Port, the inspection underscored the value of certified underwater surveys in managing structural risks and ensuring compliance with UK maritime regulations. This case highlights the necessity of proactive inspections for jack-up rigs, particularly in high-value assets where downtime costs can exceed £1 million per day.

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