API SIFE vs SIRE Source Inspector Certifications Compared

Short answer: API SIFE (Source Inspector Fixed Equipment) covers pressure-containing and structural fabrications such as vessels, columns, heat exchangers, piping, valves, pressure relief devices and tubulars. API SIRE (Source Inspector Rotating Equipment) covers pumps, gears, compressors, turbines and their auxiliaries. Both are API Individual Certification Programs with a 3.25-hour closed-book exam and a three-year term. Pick the one that matches the equipment packages your people actually witness at vendor shops; for most fabrication-heavy capital projects that is SIFE first.

This guide compares the two programmes from public API information, explains what each exam draws on, and works through the two questions owners and inspection managers keep asking: which certification is the better first step for experienced inspectors, and whether a project should require a recognised source-inspector certification for every person doing vendor surveillance. Atlantis NDT does not offer API certification training or exam preparation; the purpose here is to help you make an informed staffing and policy decision. Always confirm current details on the official API pages before you apply or write a specification.

What a source inspector actually does

API describes the source inspector as the person responsible for examining fabricated and manufactured equipment and materials at a supplier's facility and for confirming that the supplier's quality management system is being used effectively. In practice that means the purchaser's eyes in the vendor shop: reviewing the inspection and test plan (ITP), attending hold and witness points, checking material certificates against the purchase order, reviewing welding procedure and welder qualification records, verifying that the vendor's nondestructive examination (NDE) was performed by qualified people to the right procedure, witnessing pressure and performance tests, checking coatings and preservation, and signing off final acceptance before the equipment ships.

Source inspection is different from in-service inspection. An API 510, 570 or 653 inspector works on equipment that is already installed and operating under an owner's mechanical integrity programme. A source inspector works upstream of that, before the equipment arrives at site. The decisions made in the vendor shop, however, set the baseline that in-service inspectors live with for decades: the as-built thickness readings, the radiographs, the hydrotest records and the material traceability become the first entries in the equipment file. A sloppy source inspection is often discovered years later as a missing baseline or an unexplained material mix-up.

The source inspector is usually not the person performing the NDE. Radiography, ultrasonic testing, magnetic particle and penetrant testing in a vendor shop are carried out by the vendor's own NDE personnel or by a subcontracted NDE company, qualified under a written practice such as ASNT SNT-TC-1A. The source inspector's job is to verify that those examinations were done to the agreed procedure and acceptance criteria, review the results, and escalate nonconformances. That division of roles matters when you decide which credentials to require of whom.

SIFE vs SIRE vs SIEE at a glance

API runs three source-inspector programmes. SIFE and SIRE are the two most people compare, and SIEE (Source Inspector Electrical Equipment) is the third, newer member of the family. The table summarises what API publishes on each programme page; verify against the live pages before relying on any detail.

Two points stand out. First, SIFE and SIRE have no minimum experience gate, which is unusual among API programmes; API 510, 570 and 653 all require documented education-plus-experience combinations. That makes the source-inspector certifications accessible, but it also means the credential on its own tells you the person passed a knowledge exam, not that they have years in vendor shops. Second, SIEE does have an experience requirement, and it recognises an existing SIFE or SIRE as partial credit, which signals how API sees the three programmes fitting together.

What the SIFE exam draws on

The SIFE body of knowledge published by API (2024 version) lists API RP 588 as the anchor document, supported by selected sections of API RP 572 (inspection of pressure vessels), API RP 577 (welding inspection and metallurgy), API RP 578 (material verification for alloy piping), API Standard 598 (valve inspection and testing), AWS D1.1 for structural steel welding, ASNT SNT-TC-1A for NDE personnel qualification, several sections of the ASME Boiler and Pressure Vessel Code (Section II materials, Section V nondestructive examination, Section VIII Divisions 1 and 2, Section IX welding qualifications), ASME B31.3 process piping, ASME B16.5 flanges, and SSPC/NACE surface preparation and dry film thickness documents.

The categories candidates are expected to know include source inspection management programmes, project-specific inspection planning, developing a source inspection project plan, performing source inspection (codes, welding procedures and qualifications, report writing), examination methods, tools and equipment, final acceptance, manufacturing and fabrication processes, pressure vessels and piping. The publications list changes with each effectivity sheet, and API publishes a current sheet covering the November 2025 to July 2027 exam windows, so check the current sheet rather than relying on the list above.

What that reference set tells you is that SIFE is a breadth credential across fabrication quality: welding, materials, NDE awareness, pressure testing, coatings and documentation. It overlaps heavily with what a welding inspector or a fabrication QA lead already knows, which is one reason SIFE is the natural first source-inspection credential for people coming from welding or NDE backgrounds.

What the SIRE exam draws on

The SIRE body of knowledge (2024 version) is built around API's own study guide for source inspection and quality surveillance of rotating equipment, plus API Standard 610 (centrifugal pumps), API 614 (lubrication, shaft-sealing and oil-control systems), API 617 (axial and centrifugal compressors and expander-compressors), API 618 (reciprocating compressors) and API 677 (general-purpose gear units). It also references Hydraulic Institute HI 14.6 for pump hydraulic performance acceptance testing, ASME Sections II, V, VIII and IX, ASNT SNT-TC-1A, ASTM A703 and MSS SP-55 for castings, and the SSPC surface preparation standards.

The knowledge categories go well beyond fabrication: equipment risk assessment for setting the inspection level, inspection and test plan development, dimensional and visual inspection, functional and electrical testing techniques, casting, forging and machining, rotating-equipment assembly and baseplate train inspection, centrifugal pumps, electric motor drivers, gears, steam turbines, lube oil systems, reciprocating compressors, rotary screw compressors and performance testing of axial and centrifugal compressors.

In other words, SIRE assumes a machinery mindset. A candidate who has spent a career witnessing pump performance tests, mechanical run tests and string tests will find the exam familiar; a welding inspector will find much of it new. That difference, more than any market preference, is what should drive the choice between the two.

Mapping the certifications to capital-project packages

A practical way to decide what a project needs is to list the procurement packages and ask who will witness each one. On a typical refinery, petrochemical, LNG or offshore topsides project the split looks roughly like this:

• SIFE territory: pressure vessels and columns, shell-and-tube and air-cooled heat exchangers, shop-fabricated piping spools, valves and pressure relief devices, structural modules and skids, tubulars, storage tank components fabricated off site.
• SIRE territory: centrifugal and positive-displacement pumps, centrifugal, axial, reciprocating and screw compressors, steam and gas turbine drivers, gearboxes, lube and seal oil consoles, and the packaged trains that combine them.
• SIEE territory: switchgear, motor control centres, transformers, large motors, control panels and junction boxes.
• Overlap: packaged units such as compressor skids carry both rotating equipment and pressure-containing components (scrubbers, coolers, piping). The pressure parts are fabrication work; the run test is machinery work. Many owners assign one lead inspector per package and bring in a specialist for the other half.

For Gulf of Mexico and Gulf Coast work, the number of fixed-equipment packages on most projects is far larger than the number of rotating-equipment packages, simply because there are more vessels, exchangers and spools than machines. That is consistent with API's own published certificant counts: an API ICP status presentation in 2024 reported roughly 679 active SIFE certifications against roughly 185 SIRE and 36 SIEE. API does not publish which operators require which certification, and we have not seen a reliable public source on Gulf of Mexico operator preferences, so treat any claim that "operators ask for X more often" as anecdote unless it comes from the operator's own specification.

Which is the better first certification for senior inspectors?

For an experienced inspector moving into source inspection, the better first certification is the one that matches the work they will do in the next two to three years, because the credential has to be renewed on a three-year cycle and is most valuable while it reflects current practice. A few rules of thumb help:

• Welding inspectors, NDE Level IIs and IIIs, API 510/570 inspectors: SIFE is the natural first step. Most of the reference material (welding, ASME VIII, B31.3, NDE qualification) is already familiar, so the effort goes into RP 588's planning and surveillance concepts.
• Machinery engineers, rotating-equipment technicians, mechanics who have run test stands: SIRE fits their existing knowledge and is where they add the most value in a vendor shop.
• Lead inspectors who coordinate packages across disciplines: one credential plus working familiarity with the other is common; a second certification is a sensible next step once the first is established.
• Inspectors with electrical backgrounds: SIEE is the specialist route and requires documented electrical experience.

Whatever the choice, remember that a passed exam does not replace the competence that comes from witnessing tests. Many owners pair the certification with a short internal qualification: a review of the inspector's last few packages, a supervised first assignment, and familiarity with the company's own source inspection procedures and ITP templates.

Should every source inspector on a capital project hold a recognised certification?

This is a policy question for the owner, and there is no code that mandates source-inspector certification for most procurement. A sensible approach is to grade the requirement by equipment criticality rather than apply one rule to every visit:

1. High-consequence packages (high-pressure or toxic service vessels, critical compressors, long-lead items with no spare): require a recognised certification for the lead source inspector, plus documented package-specific experience.
2. Standard packages: require either a recognised source-inspector certification or an equivalent combination such as an active API 510 or AWS CWI certificate and relevant shop experience, so you do not exclude capable people with different credentials.
3. Low-risk or catalogue items: a documented competence assessment against your own procedure is often enough, with certification encouraged rather than required.

Whatever level you choose, write it into the inspection services contract and the project quality plan, define acceptable equivalents in advance, and check certificates directly with the issuing body. API offers a public lookup of individual certifications, and our guide to verifying an API inspector certificate walks through the process. For how owners write certification requirements into contractor bids more generally, see requiring API certifications in contractor RFPs.

The NDE performed in the vendor shop needs its own control. Both the SIFE and SIRE bodies of knowledge list ASNT SNT-TC-1A, which reflects the point that the source inspector verifies NDE personnel qualification rather than performing the examination. Your purchase specification should therefore state the NDE personnel qualification you expect (for example, Level II under the vendor's written practice for interpretation and acceptance) independently of the source inspector requirement.

Where source inspection meets NDE

Most of the disputes that end up on a source inspector's desk are NDE disputes: a radiograph with questionable image quality, a weld that the vendor says passes and the purchaser says does not, an ultrasonic indication on a forging, a penetrant indication on a machined surface, missing thickness baselines. Resolving them quickly depends on three things: a clear acceptance criterion in the purchase documents, evidence that the vendor's technicians are qualified under a written practice, and, when needed, an independent NDE check.

Typical vendor-shop NDE by package:

Independent NDE verification is a common owner tool on critical packages: a third-party NDE crew re-examines a sample of welds or reviews the radiographs. It is especially useful when the vendor's NDE is subcontracted to a company the purchaser has not audited.

Exam logistics, recertification and the career path

API Individual Certification Program exams are computer-based and are delivered at Prometric test centres during fixed testing windows, with remote proctoring offered for selected programmes. The source-inspector exams have several windows a year; the dates, application deadlines and published fees are on API's ICP schedules and fees page. Certification lasts three years. You can apply to recertify from 90 days before expiry, and a further 90-day grace period is available with a late fee; after that, a new application and full exam are required.

For career planning, source inspection sits alongside rather than above the in-service inspector path. Inspectors frequently hold an in-service certification such as API 510 or 570 and add SIFE when project work picks up, or start as source inspectors and later qualify for in-service programmes once they meet the experience requirements. NDE qualification is the common foundation underneath both: a source inspector who can read a radiograph or interpret a UT report with confidence is far more effective than one who can only check that a report exists. For the NDE side, see our guides to ASNT certification and NDT Level II training, and our comparison of ASNT Level II versus code inspector certification. For an overview of the in-service programmes, see the API inspector guide.

Canada and international projects

API's source-inspector certifications are recognised internationally and are commonly specified on Canadian oil sands, LNG and petrochemical projects as well as US work. For pressure equipment built for installation in Canada, remember that provincial regulators (such as ABSA in Alberta or TSSA in Ontario) have their own design registration and shop inspection requirements that apply regardless of the purchaser's source-inspection policy; a source inspector supplements, and does not replace, the jurisdictional inspection of pressure equipment. Confirm the regulatory route for each package with the jurisdiction where the equipment will operate.

How Atlantis supports this

Atlantis NDT does not provide API certification training or act as a source inspection agency. We support source inspection programmes with the NDE itself: vendor-shop and fabrication-yard radiography, ultrasonic testing and phased array UT, magnetic particle and penetrant testing, visual examination and baseline thickness surveys, performed by ASNT-certified technicians under ASNT Level III oversight and reported against the purchaser's inspection and test plan. Independent NDE verification on critical packages is a typical scope. See our full inspection services. Quotes are returned within 24 hours: request vendor-shop NDE support.

Frequently asked questions

API SIFE versus API SIRE: which one do GoM operators ask for more often on source inspection and capital project scopes?

There is no public data on individual operators' preferences. What is public is that API reported far more active SIFE certifications than SIRE in 2024, and most capital projects have many more fixed-equipment packages than rotating-equipment packages, so SIFE is the more frequently held credential. Check each operator's own specification for its actual requirement.

Which is the better first cert for my senior guys?

Match it to the work. Senior welding, NDE and in-service inspectors usually start with SIFE because the reference material overlaps their experience. Senior machinery and rotating-equipment people usually start with SIRE. A second certification can follow once the first is established.

As an offshore HSE director, should I require a recognised source inspector certification for every source inspector on our capital projects?

No code requires it for most procurement, so it is a policy choice. A graded approach works well: require certification for lead inspectors on high-consequence packages, accept defined equivalents for standard packages, and use internal competence assessment for low-risk items. Put the rule in the contract and quality plan.

What is an API source inspector?

API defines the source inspector as the person who examines fabricated and manufactured equipment and materials at the supplier's facility and confirms the supplier's quality system is working. They act for the purchaser before equipment ships.

What does API SIFE cover?

Pressure-containing and structural equipment: vessels, columns and towers, heat exchangers, piping, valves, pressure relief devices, tubulars and associated structural fabrications. API RP 588 is the main reference.

Do I need experience to sit the SIFE or SIRE exam?

API's programme pages state that SIFE and SIRE are open to people with any level of petroleum and petrochemical experience or those seeking it, and that employment verification is not currently required. SIEE has a documented electrical experience requirement.

How long is the SIFE or SIRE exam and where do I take it?

Each exam runs 3.25 hours with about 110 closed-book multiple-choice questions. API ICP exams are computer-based at Prometric test centres during scheduled windows, with remote proctoring offered for selected programmes. Check the API schedules page for current dates.

How often do I need to recertify?

Every three years. The recertification window opens 90 days before expiry, and a 90-day grace period with a late fee follows. Miss that and you must reapply and retake the exam.

Does a source inspector perform NDE?

Usually not. Vendor or subcontracted NDE personnel qualified under a written practice such as SNT-TC-1A perform the examinations; the source inspector verifies procedures, qualifications and results and makes the acceptance call for the purchaser.

Can Atlantis provide NDE during vendor-shop source inspection?

Yes. Atlantis performs RT, UT, phased array, MT, PT and visual examination at fabrication shops under the purchaser's inspection and test plan, including independent verification of vendor NDE. Ask for a quote.

Planning inspection resourcing for a capital project? Talk to our NDE team about vendor-shop examination scopes.

Sources: API programme pages for SIFE, SIRE and SIEE; API SIFE and SIRE bodies of knowledge (2024); API ICP status update (April 2024). Programme details change; confirm on api.org.