Section 2 Special consideration process

2.1.1 To ensure that special consideration is undertaken in a consistent manner, with an appropriate degree of rigour and in compliance with the applicable Classification and Certification (Rule) requirements for materials, the Special Consideration process shall be conducted in accordance with the steps given in Ch 1, 2.1 General 2.1.2.

2.1.3 In general, communication between LR and Client will be through the local office.

2.2.1 The Client initially informs LR of the intention to use a material that is out of the scope of the Rules at the concept or design stage.

2.2.3 An initial review is undertaken to confirm that the proposal qualified for special consideration. Based upon the outcome of the initial review conducted by LR, the Client will either receive an acceptance or rejection in principle, including the reasoning that led to the decision. It is possible for the Client to appeal against this decision and provide further justification to support their case.

2.2.4 In order to ensure an efficient review process, Clients should submit the information listed in Ch 1, 2.2 Step 1: Initial review of Client's proposal 2.2.2 as comprehensively as possible. Discussions at an early stage (e.g. concept design stage) with LR specialists are encouraged for a smooth and timely approval process.

2.2.5 The initial review will be based on the information submitted in conjunction with stress calculations submitted by the Client, which may not have been independently verified by LR. If during the subsequent LR design appraisal stage, the designed service conditions (including load conditions, stress levels, environment etc.) for the material application concerned are found to be incorrect, it will be the responsibility of the Client to ensure appropriate action is taken to achieve compliance. This may result in the initial review stage of the Special Consideration process being repeated.

2.3.1 Further to the positive outcome of the initial review and an acceptance in principle, LR will identify the specific concerns highlighted during the initial review of the proposal. The result will be a list of further considerations or specific concerns to be addressed by the Client.

2.3.2 The further considerations or specific concerns need to include all root causes of the specific failures in material function and performance through-life.

2.3.3 The further considerations and the specific concerns may include, but are not limited to:

1. Concerns raised due to the restriction of the Rule requirement, i.e. the reason why the material application is not in the scope of the current Rules and Regulations;
2. Reported failures in similar industrial applications;
3. Engineers’ and specialists’ knowledge and experience in the areas relevant to the material application;
4. Applicable concerns from previous similar cases;
5. Possible failures identified by the Client based on their knowledge and expertise;
6. Risks associated with this material application with respect to possible material failures.

2.3.4 In particular regard to item (f) of Ch 1, 2.3 Step 2: Identification of specific concerns 2.3.3, the specific material failures shall be scrutinised throughout all the scenarios of the material life span as categorised in (a) to (i) of this paragraph, if applicable, in order to identify the specific concerns that could act as the root causes of the possible failures:

1. Design accuracy and safety margin demonstrated in structural and stress analysis and calculation reports, etc., where applicable;
2. demonstrated in structural and stress analysis and calculation reports, etc., where applicable;
3. Material selection, where the relevant design codes, material standards and material selection principles or methods shall be referred to;
4. Manufacturing processes, including technology and capacity, chemical composition and microstructure (if applicable), processes and quality control, sampling and testing, and maximum permissible manufacturing defects;
5. Material property degradation during the fabrication processes, e.g. cutting, forming and welding/joining, such as strain ageing, welding HAZ properties and susceptibility to hydrogen cracking and embrittlement of high strength steels from supporting documents such as associated welding procedures and qualification records, testing and inspection plans and acceptance criteria;
6. Material property degradation due to the service environment, such as chemical attack (e.g. hydrogen embrittlement and stress corrosion), and service temperatures;
7. Material property degradation in extreme load conditions, including impact and strain rate effects, fatigue propagation etc.;
8. Sampling, testing and procedure qualifications shall be representative of the worst case scenarios; Quality control and inspection practices including acceptance criteria and procedures, with the achievable detection limits of the techniques in use;
9. Service records and periodic inspection reports, if existing structures/machinery are involved.

2.4.1 The identified concerns are then communicated and discussed with the Client in order for them to provide evidence and/or take measures to address and mitigate them.

2.4.2 In order to eliminate the root causes of possible failures, as listed in the specific concerns and identified in step 2, the Client shall agree to take measures and to demonstrate that the possible failures shall be prevented sufficiently and effectively. Submission of such measures shall include, but are not limited to, the following items:

1. Works approval status of the material supplier;
2. Capabilities of the material fabricator, e.g. company’s historical data and product performance records, if available;
3. Sufficiently detailed stress calculations and fatigue assessments for all required design conditions;
4. Manufacturer or fabricator’s Inspection and Testing Plan (ITP);

   The ITP shall provide useful information on the quality control aspects identified by the manufacturer, based on which local LR Surveyors can examine the execution of manufacturing and the ITP. An ITP shall include a minimum of the following aspects:

   • Material designations and specifications in accordance with recognised National and/or International Standards.
   • Details of the material manufacturing and heat treatment processes, including quality control aspects.
   • Mechanical testing plans and procedures, including sampling plans, frequency and acceptance criteria.
   • Material fabrication/welding procedures, quality control and inspection plans, including welding repair procedures if applicable.
5. A specific testing program and defined acceptance criteria based on the concerns raised during the “initial review” and “identification of specific concerns” stages, if applicable. The Client’s research regarding the material service conditions, expected material behaviour/performance and life span, including possible analysis of material failure modes and material related structural failures, if available;
6. Level/extent of NDE, which needs to be suitable for the design details and the application of the proposed material and weld types;
7. Findings from relevant research regarding the aforementioned aspects, if available;
8. Any applicable test results regarding the aforementioned aspects, if available;
9. Inherent safety factors relating to the material application.

2.5.1 Technical justification is to be conducted based on a review of the information listed in Ch 1, 2.4 Step 3: Discussion and submission of measures 2.4.2 as submitted to LR by the Client.

2.5.2 If during the review, a need for additional information is identified, this will be requested from the Client.

2.5.3 LR will assess whether the measures taken have adequately and effectively addressed the concerns, and whether the material application can ensure the structural integrity, safety, and component performance in service. Justification and evidence offered to address the concerns raised may take the form of the following items:

• Material specifications and requirements for material quality and selection are demonstrated as being suitable for the design purpose by means of Structural Integrity and Safety Assessment or Fit For Service Assessment in compliance with the relevant Standards, if necessary;
• Conservatism in the design calculations for the load cases, and service/environment conditions;
• Sufficient manufacturing capability demonstrated with product history and performance data, if available;
• Testing results, particularly with regard to the sampling procedure for the representative properties and worst-case scenarios;
• Sufficient capability of fabrication practices, inspection and quality control for a minimum level of defects in a new build structure;
• Risk of material failure in service related to material properties mitigated.

2.6.1 Where applicable, the LR Surveyors on site will be informed of the agreed requirements for the manufacturing and testing procedures. These will include activities requiring LR witnesses during manufacturing, material testing, fabrication and inspection, in order to verify compliance during the manufacturing and construction stages.

2.6.2 Confirmation of compliance with the agreed requirements shall be documented. In the case of non-compliance, it shall be resolved prior to the product entering into service.