Some important QA-elements and QA-tools in engineering and design

“QA-elements” in this context means the procedures, etc. that are required for the Quality System to satisfy the 20 main requirements in the ISO 9001:1994 standard. These elements have been given the numbers 4.1 to 4.20 in the standard. “QA-tools” are used as a less precise term for certain specific techniques and tools that will contribute to fulfilling the requirements effectively. Some of those elements and tools have been described in brief below, namely qualifying key personnel, Self-Check, Discipline Check (DC), Inter Discipline Check (IDC), Third Party Verification, Design Review (DR), Hazard and Operability Studies (HAZOP), Worst-Case Analysis and Quality Audit.

Fuller descriptions are given in Appendices B-H.

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(a) Qualifying key personnel

In design of concrete structures, as in other high technology projects, one of the most important preventive measures is ensuring that fully qualified personnel are assigned to the key positions. Before anyone is appointed, it should be made clear which basic qualifications and what type of experience, for example from similar projects, are required. Subsequently, the most suitable candidates should be selected based on CVs, references and interviews. Finally, the candidates should be asked to outline how they will attack the task, and the answers evaluated.

(b) Self-Check

All analyses, calculations and documents should be thoroughly self-checked, that is to say checked by the person or persons who have carried out the work, before the results are passed on to others. As mentioned, the policy should be to make everything right the first time.

Fig. 6.1 shows the relation between Self-Checks and the other elements in the verification process.3 _{When Fig. 6.1 is read vertically, the order of the different checks appears. Thus, all}

documents and drawings should first be subject to a Self-Check, i.e. a check by the same person who is carrying out the task. If a nonconformity (NC) to the specification for that particular task is observed it should be corrected at once, i.e. before the document or drawing is passed on. The relevance of the subsequent checks depends on the criticality of the document or drawing. If the task has no criticality classification at all, the result would pass on to a Design Review (if required) or directly for approval. If classified I, II or III (see Table 6.2) the document or drawing would be subject to a Discipline Check at a suitable level. Documents or drawings of Criticality II and III would in addition be subject to an Inter Discipline Check (if relevant). The most critical results (Criticality III) would finally be subject to a Third Party Verification as well.

If nonconformity is detected during these checks, the document or drawing will, of course, have to be corrected or re-worked. In Fig. 6.1 this is indicated by the dotted feed-back loops.

Design Review, Discipline Check, Inter Discipline Check and Third Party Verification are more closely examined below and in Appendices B—E.

(c) Criticality

The amount or level of quality assurance of documents and drawings should reflect their importance (level of criticality), which could be decided by a qualified person or by a Design Review. The criticality should be clearly stated in the document. This is to ensure that the level of attention coincides with the document’s importance in relation to quality, safety, environment and/or economy. Three levels of criticality are described in Table 6.2. In engineering and design of Gravity Base Structures (GBS’s) a major part of the technical calculations, documents and drawings will in principle be of Criticality III. However, as indicated in Fig. 6.1, there are still several possibilities for tailoring the amount of quality control to a suitable level.

(d) Discipline check (DC)

A Discipline Check is an inspection to ensure that the technical documentation satisfies all internal and external requirements within one’s own discipline before further distribution and use. In order to be acceptable, a Discipline Check has to be independent, i.e. carried out by a competent person or body other than the one(s) that drew up the documents, or were responsible for or involved in the process in some other way. This goes for the other types of

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verification as well, except for Self-Check. However, as mentioned above, the necessary level of independence may vary according to the criticality of the document or drawing.

The reason for the principle of independent checks is that, according to many years of experience, it is usually much easier to discover mistakes, defects and weaknesses when it comes to other’s work than one’s own. In addition, those who carry out the checks should not be under any influence or pressure that could have a negative impact on quality. Such a pressure would, for example, exist if the person(s) carrying out the checks would also be held responsible for lost time or additional costs resulting from detecting and correcting errors. Discipline Check (as well as Third Party Verification; see Fig. 6.1) can be carried out on four different levels:

Level 1: Document Review

Level 2: Extended Document Review Level 3: Independent Calculation Level 4: Scale Test

For a further description of Discipline Check, as well as the four above-mentioned levels, see

Appendix B and Chapter 7, Verification of design.

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(e) Inter discipline check (IDC)

An Inter Discipline Check is an inspection and a review of technical documentation to ensure that it fulfils all internal and external requirements and considerations for other (i.e. interfacing) technical disciplines before further distribution and use. The check should be carried out by competent persons from the relevant other disciplines.

An Inter Discipline Check is an independent check. It comes after, and in addition to, Self- Check and Discipline Check (see Fig. 6.1). It is carried out only when an interface to other disciplines exists.

The Inter Discipline Check has been further described in Appendix C.

(f) Third party verification/External verification

A Third Party or External Verification of documents and drawings consists of Document Review (Level 1), Extended Document Review (Level 2), Independent Calculations (Level 3) or Scale Test (Level 4) carried out by a different company or organization than the one responsible for the executed work (Fig. 6.1). Third Party Verification may also include external Quality Audits to verify that the quality system is effective.

From the authorities’ point of view, the main aim of Third Party Verification is to obtain objective evidence that the requirements have been met. The operator could therefore be instructed to carry it out. From the point of view of the operator and the personnel involved in engineering and design, it is important that the Third Party Verification is synchronised with the design work. The reason behind this is that the verification can and should give effective support and current corrections to design. This has been further explained in Chapter 7, Verification of design.

4 _{Note that several publications and companies use the opposite order, i.e. Level I is the most critical, Level III the least critical. The reason}

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Third Party Verification can be costly and should therefore only be used to identify and verify the most critical parts of the structure (Criticality III, see Table 6.2). For further description, also see Appendix D.

(g) Design review (DR)

Briefly explained, a Design Review is a systematic, independent review of the design and the way it is documented. In general, Design Reviews should at least be carried out between the main activities or phases of the project (see Fig. 6.2). The general aim is to optimalize the design solutions. The reviews should be carried out by groups of persons who have the relevant technical background and experience, among other things, in order to obtain synergetic effects and make the most of the available competence.

For further description of Design Review, see Appendix E.

(h) Hazard and operability studies—HAZOP

A HAZOP is a formal, systematic and critical review of different parts of a system, design, plant or structure in order to identify potential problems regarding safety and operability, so that risk-reducing actions can be implemented. The analysis could be a complete risk analysis or a pre-study for more detailed studies of critical parts of a structure. HAZOP can be carried out both during pre-engineering and detail design. The analyses could also be carried out during operations, e.g. in connection with maintenance or modifications of the design or the operational procedures. For further description, see Appendix F.

(i) Worst-case analysis

A Worst-case analysis is a systematic analysis and evaluation of the consequence of the worst possible input data, occurrences and combinations of occurrences, to personnel, the environment and assets.

The purposes of a Worst-Case Analysis are two-sided (for further description, see Appendix G):

• To verify that safety and other important functions are maintained under abnormal loads, foreseeable abuse and abnormal human stress.

• To ensure that decisions on not designing and dimensioning for such extreme conditions are made on the right (i.e. high enough) level in the organization.

(j) Quality audit/Quality system audit

A Quality (System) Audit is, simply put, a systematic and independent review or investigation to ensure that the Quality System is properly designed and implemented. Audits should be carried out according to written procedures.

Quality Audits have been greatly emphasised as an important management tool during the last decades. Requirements have been made to ensure that the audits are carried out both in NPD’s Internal Regulations and in ISO 9001. However, it can be argued that practice within this area has developed in a somewhat unfortunate direction. Especially within offshore applications, attention has been drawn primarily to audits of written quality system descriptions and procedures. The question could be raised, whether this may have been at the sacrifice of attention on the quality of the actual product.

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6.3.3 Quality Assurance elements related to the main activities in engineering and