What Do You Think…?

?What Do You Think…

Periodically, the Condenser publishes articles that present an author’s point of view and commentary on a topical issue of interest to the industrial refrigeration industry. In the basis for inspections and tests. The IIAR bulletins stipulate only that the inspector must be “competent”. this column, we will briefly examine a trend and ask for your feedback, your thoughts, and your observations. In this issue, we take a look at…

The Case for Qualification and Certification of Mechanical Integrity Inspectors

By Keith A. Tyson

It is time for your plant to have a third-party inspection. How do you decide who to use? Before an inspector is hired, the owner/manager of the equipment has a right – and a responsibility – to know answers to the following: • What assurance is there that the inspector has the knowledge and ability to perform the inspections or tests? • Does the inspector have enough experience and training to support the report’s conclusions? • What makes the report on equipment condition credible? • Can a report that recommends the repair or replacement of equipment to meet safety requirements be trusted? • Can I sleep at night believing a report that states no harm or damage is likely to result from continued use of the inspected equipment? • Is there a system that allows me to have confidence in an inspector’s methods, procedures, and reports?

These questions are common to most industries. Dependable answers are provided by a standardized written program and procedure for the qualification, training, and certification of inspectors.

Other industries have requirements for inspectors. Nearly all pressure vessels and exchangers have ASME certifications which denote, at some point in their assembly, the inspection or testing by a person holding specific credentials. The methods of training, qualification, and certification for these inspectors are codified and well known. This assures the owner that that equipment is suitable for the conditions in which it will operate.

Ammonia refrigeration systems are required to be inspected and tested in order to comply with OSHA’s PSM mandates. These duties must be performed in accordance with “recognized and generally accepted good engineering practice”. This is commonly interpreted as conforming to ANSI/IIAR-2, Bulletin 109, and Bulletin 110 which provide Bulletin 109, paragraph 5.3, states that “A more thorough inspection…should be conducted by a competent ammonia refrigeration engineer … every five years.” Bulletin 110 adds, in paragraph 6.4.4.1,“…the annual inspection of the vessels and heat exchangers shall be carried out by a competent person independent of immediate commercial and production pressures for that installation…” No other requirements for the inspector are provided. There is a growing awareness by auditors that the industry standard does not adequately address inspector qualifications. In fact, recent OSHA audits of refrigeration systems have found persons previously thought “competent” to be inadequately equipped for inspection duties. If the question is “How do we know the inspector is competent?” The logical response is “An inspector should be qualified, trained, and certified to perform the inspection and tests.” The process begins with the development of written inspection and test procedures. Although details of these are beyond the scope of this article, the documents should state inspection goals as well as the minimum qualifications for inspectors —including a certification level. The procedures ought to specify whether the inspector may be a facility employee or must be an independent contractor. If the inspection requirements are clearly stated, then the final report will yield relevant information.

Qualification of the Inspector

A written inspection program defines the amount of training required based on the combination of education and experience. This is known as qualification. The training required for an individual factors in educational level, previous training, and related work experience. A new hire with a high school education and no ammonia refrigeration experience requires a great deal more instruction than an operator who has had refrigeration training and work experience. A person with pertinent higher education, such as an engineering degree, will likely not need as much preparation. It is useful to observe the training programs required for individuals who perform inspections and tests in other industries, such as petroleum or chemical. The employers of such inspectors use The American Society for Nondestructive Testing, Inc Recommended Practice No. SNT-TC-1A. This guideline provides a standard methodology for the qualification, training, and certification of inspectors. Most

design codes including ASME Section VIII, Div. 1, Unfired Pressure Vessels, contain reference to this document for inspectors who perform certain non-destructive examinations. Inspections and tests are not valid unless the inspector is certified in accordance the written practice of the inspector’s employer, which must meet SNT-TC-1A standards.

A written practice that uses SNT-TC-1A guidance will categorize inspectors into three levels identified by Roman numerals I, II, and III. It will stipulate the amount of training, in hours, that are needed for each level of certification based on the educational and work experience of the candidate. Higher levels of education or experience will usually require fewer hours of training.

A person who has not yet attained Level I is known as a trainee. A Level I inspector can perform certain aspects of the test but may not be able to sign off on the results. A Level II can perform all inspection duties and may also assure that the Level I’s work was proper and certifies the test results, in other words, supervise a Level I. A Level III is the person who writes the procedures and examinations, performs training and qualification, and certifies a person as meeting the requirements for inspector Level I or II. The Level III is also responsible for development of the training and certification program which is known as the Written Practice.

SNT-TC-1A is simply a guide. It does not address the details of the required training. It does not contain a “how to” about training or even materials for the candidate to study. It only offers recommendations on the number of hours and topics that should be discussed as part of the training. It is the duty of the employer or the Level III to develop the required training programs and certifications. Therefore, a Level III inspector must be knowledgeable of the inspection or test method that will be used and in the requirements of the code or standard that must be met. It is clear that the Level III must have extensive experience along with comprehensive knowledge of the codes and standards used in ammonia refrigeration.

There are guidelines in the SNT-TC-1A for the certification of a person as Level III. The American Society of Nondestructive Testing conducts tests on a national scope to certify Level III inspectors in various inspection methods. A person holding this ASNT Level III certification can be either the company’s employee or a contractor. To use a contractor as Level III the company generally creates a document known as a “letter of appointment” that gives the person, by name, the authority to be a Level III. Another approach is to generate a certification test, usually by a contracted ASNT Level III, to test a person employed by the company to hold a Level III position. The Level III’s certification is limited to the employer only and usually cannot be transferred to another company.

Another requirement for certification as an inspector is that of a physical or eye examination. We want to determine that a candidate has good eyesight in order to conduct the inspections to ascertain that they can see print of a certain size which may be important in reading nameplates or drawings. The eye examination may determine that the candidate may only perform the tests with corrective eyewear and this becomes a condition of the work performed. The eye examination may be conducted by the Level III using standard eye charts, or the candidate may be tested by a local optometrist. Eye examinations are required annually.

Training of the Inspector

Obviously, ammonia refrigeration experience is a plus for candidates who will perform inspections. The more knowledge they have of the refrigeration process and associated equipment, the more they will understand and identify any deficiencies. A facility-employed operator can be a good candidate for inspector if that person is capable of looking at the system with an eye towards compliance. On the other hand, flaws can be overlooked because of familiarity with the system. For example, a component may have been installed improperly or without a required safety device. If the condition has been such the entire time the operator has known it, that flaw may be overlooked as a compliance issue. It is not uncommon to point a deficiency out to a long-term operator and hear him say, “I never noticed that before”.

The inspector will receive training based on the qualification level as described earlier. Less qualification means more training; more qualification allows advanced topics. Training will cover three basic areas, namely, the “how to’s” of the inspection method; all requirements of the associated codes and standards; and the acceptance criteria. Once training is completed, the inspector should be able to perform the test properly and determine the results correctly.

There are numerous inspections and tests that are used in mechanical integrity. Inspections are performed by humans using a visual means of observation, either directly or indirectly with a scope or camera of some sort. Tests are performed with some instrument, gauge, or logic used to determine that an object meets a minimum standard such as material thickness, system tightness or expected action. A test may be monitored by humans, computers, or some other means (think canaries).

Inspection methods or tests may require specialized equipment or techniques such as ultrasonic thickness testing, vibration analysis, or thermographic imaging. The inspector must receive adequate training to perform these examinations properly. He must be knowledgeable of the testing equipment, how to conduct the test, and how to interpret results. SNTTC-1A provides a guideline on how much training each test method should reasonably require. The training would also include a number of hands-on, or OJT, hours under the supervision of a trainer or a qualified inspector as tests are conducted on actual equipment.

Once the inspector knows how to perform the test, training then moves to why the inspection or test is being performed. The specific code or standard is introduced and the requirements are explored. The standard may state briefly that “an annual inspection” must be conducted. This becomes mandatory and the inspection must be performed. Our industry uses the checklists provided in Bulletin 109 to document those inspections. The training should cover all the codes and standards relevant to the system to glean the minimum requirements or acceptance criteria. The inspection checklist is also a guide for the inspector in conducting the inspection. The inspector must have knowledge of the construction codes in order to perform the inspection completely.

Once the training hours have been met, the candidate is then qualified to be an inspector. The person has the prerequisite education or work experience, the required training hours, and the prescribed field experience conducting the test. The candidate is now ready for certification.

Certification of the Inspector

Certification is the process of testing the inspector in order to verify proficiency in the test method as well as the ability to actually conduct the examination and interpret the results correctly. The Level III is responsible for the testing and certification of all inspector candidates. Tests are generated to demonstrate that the candidate has a good knowledge of the codes and standards, the correct method for performing the test, and suitable acceptance criteria. The formal test will be proof that the person is qualified to conduct the test or inspection and, thus, the reported results can be trusted.

The tests to be administered to the candidate are broken into the following three areas: General, Specific, and Practical. Each section of the test contains a prescribed number of questions relating to the inspection method. The questions may be generated from industry guidelines or specifically written by the Level III. SNT-TC-1A provides guidelines for the number of questions to be administered in each area and the minimum number of correct answers, stated as a percentage. The final score of the test is a weighted average of the three sections. Each section must be passed independently, with the final score reaching a minimum level. The following example demonstrates the number of required questions and minimum passing percentages for a candidate performing visual inspections: • General Questions 40 Pass 70 percent • Specific Questions 20 Pass 70 percent • Practical Questions 20 Pass 70 percent

A failing grade in any area reveals a weakness that must be addressed in order to have an inspector whose tests can be fully trusted. More training is provided in the areas that were failed and then the candidate may be retested. Failure of one or more sections usually requires a retest of all sections.

General questions pertain to the inspection method as well as problems that may be encountered in real life. The questions should demonstrate a broad knowledge of refrigeration conditions that can be detrimental to mechanical integrity. For ammonia refrigeration, the questions should cover corrosion and what conditions can cause it, insulation applications that are likely to be observed, and different types of equipment. Various valves and conditions that may be encountered are also areas that could be addressed.

Specific questions are generated directly from the codes and standards that are used in ammonia refrigeration. These questions may be along the lines of such topics as minimum thickness, pressure rating, or hanger spacing. This portion of the test is “open book,” meaning that the candidate will need to know where the paragraph exists and demonstrate the ability to interpret correctly the meaning of the test. The answers are required to have a reference to the paragraph by number to show that the candidate is not working from memory.

The practical test is an actual inspection or test of a component to demonstrate the candidate can observe and interpret discrepancies in a real object. The test can be with real components or, more effectively, photographs of components with a number of problems. A photograph of a piece of equipment can be presented and the candidate is asked questions about the object to demonstrate that the discrepancies can be discerned.

The Level III reviews and scores the test. The scores are recorded on forms and then signed by the Level III which becomes the inspector’s certification. The certification is usually good for three years and a retest is required at that time. Also, the Level III may require retesting if he has cause to doubt the inspector’s abilities.

Conclusion

The training, qualification and certification of the inspector is a crucial element of any mechanical integrity inspection. It may not have been an issue in the past, but recently there have been OSHA audits questioning the credentials of certain ammonia refrigeration inspectors. This, in turn, undermines the validity of any report generated by an inspector of dubious suitability.

A roadmap has been developed by ASNT that has served other industries well. This can be readily applied to our industry to yield reliable results in inspections and tests. Begin with a thorough review of your inspection requirements and develop the guidelines that will provide the integrity of your mechanical integrity program. If these functions are performed in-house, define the qualifications needed and develop training and certification procedures. If these duties are contracted out, stipulate requirements to those contractors. Above all, obtain certification documents for all inspectors who provide mechanical integrity reports. In the end, the process will be structured, based on solid practices, repeatable, and reliable. Then we all sleep better.