API 510 Pressure Vessel Inspection Support in Ontario

Short answer: In Ontario, every regulated pressure vessel needs a current Certificate of Inspection from the Technical Standards and Safety Authority (TSSA) under Ontario Regulation 220/01 (Boilers and Pressure Vessels). The periodic inspection behind that certificate is done by a TSSA inspector for uninsured equipment or by the boiler and machinery insurer for insured equipment, by a person holding an Ontario Certificate of Competency. Refiners and chemical plants layer API 510 on top as the engineering practice for in-service inspection. Atlantis NDT performs the nondestructive examinations those inspections depend on and hands the data to the inspector who signs.

Ontario is a useful case for being precise about roles. The provincial rules do not name API 510 as a legal requirement, yet almost every refinery, petrochemical plant and large chemical site in the province manages its vessels to API 510 because it is the recognised in-service code, because their corporate mechanical-integrity standards require it, and because the inspectors working on those sites are trained in it. Atlantis performs the NDE; your API 510 Authorized Inspector remains inspector of record and signs the inspection report. In Ontario terms, the person who signs the jurisdictional Record of Inspection is the TSSA inspector or the insurer's inspector holding an Ontario Certificate of Competency, and the owner's API 510 inspector usually runs the internal programme alongside them. To start, request an NDE scope for your inspector's plan.

Where API 510 pressure vessels are in Ontario

Direct answer: Ontario's process vessels are concentrated in Sarnia and Lambton County (refining, petrochemicals and specialty chemicals), at the Nanticoke refinery on Lake Erie, in the steel, chemical and manufacturing belt around Hamilton and the Greater Toronto Area, at nuclear and gas-fired generating stations, and at mining, smelting and pulp and paper operations across the north.

Sarnia, Corunna and the St. Clair River

The stretch of the St. Clair River from Sarnia south through Corunna holds the province's densest population of refinery and petrochemical vessels. Two refineries operate in Sarnia and a third sits at Corunna, alongside an ethylene cracker and polyethylene plants, synthetic rubber and specialty chemical producers, a nitrogen fertilizer complex just downriver at Courtright, hydrogen and industrial gas plants, and a growing cluster of bio-based chemical and renewable fuels projects. Typical vessels include crude and vacuum unit drums, hydrotreater and hydrocracker reactors and high-pressure separators, fluid catalytic cracking regenerators and fractionator overhead drums, amine contactors and regenerators, sour water strippers, caustic treaters, cracked-gas and refrigeration drums, ammonia synthesis separators and many shell-and-tube exchangers. Damage mechanisms range from wet H2S cracking, amine and caustic stress corrosion cracking and ammonia stress corrosion cracking to high-temperature sulfidation, hydrogen-service concerns in hydroprocessing and chloride attack in overhead systems. Background: NDT consulting in Sarnia, NDT training in Sarnia and a digital twin for Sarnia-area assets.

Nanticoke and the Lake Erie shore

The Nanticoke refinery in Haldimand County supplies much of southern Ontario, and the industrial area around it includes a large integrated steel works. Refinery vessels there follow the same API 510 logic as Sarnia, but the long run lengths between major turnarounds put pressure on on-stream inspection, corrosion mapping at fixed CMLs and careful planning of which internals must be seen during the outage. See the Nanticoke digital twin page for how inspection data can be organised on a site model.

Hamilton, the Greater Toronto Area and the Golden Horseshoe

Hamilton's harbour is lined with steel mills, which run oxygen and nitrogen receivers, compressed-air and process-gas vessels, deaerators and pickling-line equipment. Around the Greater Toronto Area, Mississauga, Oakville, Brampton and Whitby host chemical blending, pharmaceutical, food, packaging and automotive plants with jacketed reactors, autoclaves, receivers, and a long tail of air receivers and steam equipment that TSSA inspects on its periodic cycle. These sites rarely run full API 510 programmes for every receiver, but their reactors, autoclaves and hazardous-service vessels often do. See NDT consulting in Hamilton and NDT consulting in Toronto.

Power generation and nuclear

Ontario's nuclear stations at Bruce, Pickering and Darlington and its gas-fired and cogeneration plants carry feedwater heaters, deaerators, moisture separators, condensers, blowdown tanks and auxiliary vessels. Pressure-retaining components in nuclear plants fall under CSA N285.0, which TSSA's code adoption document also adopts, so nuclear work follows its own programme and is outside the scope of an API 510 hub. Conventional balance-of-plant vessels at gas-fired and industrial cogeneration sites, however, are ordinary O. Reg. 220/01 equipment.

Northern Ontario: mining, smelting and pulp and paper

Sudbury's nickel and copper smelters and refineries, gold and base-metal mines from Timmins to Red Lake, and pulp and paper mills at centres such as Thunder Bay, Espanola and Kapuskasing run autoclaves, acid-plant vessels, digesters, black-liquor and steam equipment and large air receivers. Pressure oxidation autoclaves and acid-service vessels bring their own damage mechanisms (erosion-corrosion, acid attack, lining failures) where wall-thickness mapping and lining-backed UT are useful. See practical NDT in Sudbury.

What API 510 requires, in plain terms

Direct answer: API 510 (11th edition, October 2022) covers in-service inspection, repair, alteration and rerating of pressure vessels. It requires external inspections, internal or on-stream inspections at intervals tied to measured corrosion, thickness measurement at condition monitoring locations, corrosion-rate and remaining-life calculations, pressure-relief device control, and authorised repair and alteration practices, all under an API-certified inspector.

External inspections. API 510 asks for visual external inspection of each vessel at a regular frequency, looking at insulation, coatings, supports, nozzles, grounding, evidence of leaks and corrosion under insulation. In Ontario the jurisdictional periodic inspection has its own maximum interval (below), so most owners align the API 510 external with it.

Internal and on-stream inspections. In paraphrase, API 510 sets the internal or on-stream inspection interval at the lesser of ten years or half the remaining corrosion life, unless the owner applies a risk-based inspection programme that meets the code's conditions. On-stream inspection can replace an internal inspection where the code's criteria are met and the inspector judges that the NDE can find the damage expected. For the arithmetic, see API 510 interval calculation explained; for sour service, API 510 intervals in wet H2S service.

Thickness, corrosion rate and remaining life. Thickness readings at condition monitoring locations (CMLs) feed short-term and long-term corrosion rates. Remaining life is the difference between the current thickness and the required thickness divided by the governing rate. These numbers are only as good as the readings: consistent CML locations, calibrated equipment, the right technique for the surface and temperature, and honest flagging of anomalies.

Relief devices, repairs and rerating. API 510 expects pressure-relief devices to be tested and inspected on a controlled interval, and it sets out who may authorise and accept repairs, alterations and rerating. In Ontario, repairs and alterations also fall under TSSA's adopted rules, with the National Board Inspection Code used as a guide; owner-user organisations that want to inspect their own repairs need TSSA accreditation (see the regulations section).

Fitness-for-service and RBI. Where measured damage exceeds simple acceptance criteria, the owner's engineers or a specialist may run a fitness-for-service assessment, and owners with mature programmes often use risk-based inspection to set intervals. We do not perform either; we provide the thickness data, corrosion maps and flaw sizes those assessments rely on. The code text is copyrighted; check the current edition and any addenda at api.org rather than relying on summaries, including this one. A broader explainer is at the API 510 pressure vessel inspection code.

NDE methods for API 510 work in Ontario

Direct answer: UT thickness surveys and automated corrosion mapping provide CML data for Sarnia, Nanticoke and chemical-plant vessels; PAUT, TOFD and wet fluorescent MT target cracking in amine, caustic, sour and ammonia service; ET covers exchanger tubes; RT, PT and VT complete weld and condition coverage.

Every method is chosen to match the damage mechanism the inspector's plan names. We document coverage, scan density and areas not examined, so nobody mistakes partial coverage for full coverage. Ontario winters create a distinct corrosion-under-insulation pattern where cladding is damaged and insulation is wetted through freeze-thaw cycles; see CUI inspection support. For damage mechanisms in depth, see the API 571 guide.

Industrial radiography in Canada is regulated federally, not provincially. The Canadian Nuclear Safety Commission (CNSC) licenses exposure devices and certifies exposure device operators, so RT on Ontario sites is performed only by crews holding the required CNSC licence and certifications. More: CNSC requirements for radiography.

How Atlantis supports your inspector

Direct answer: Atlantis turns the inspector's plan into Level III-reviewed NDE procedures, performs the examinations with ASNT-certified technicians, flags questionable readings while access remains, and delivers a digital report the inspector evaluates. We are not an Authorized Inspection Agency and we do not supply API-certified inspectors, and we are not a TSSA-authorised inspection provider.

On Ontario sites the inspection chain usually has three parties: the owner's own API 510 inspector or integrity group, the jurisdictional inspector (TSSA or the insurer's inspector holding an Ontario Certificate of Competency) who issues the Record of Inspection, and the NDE contractor. We work for the owner as the third party:

1. Plan intake. Equipment list with TSSA identifiers and CRNs, the inspection plan, CML maps, damage mechanisms, the last inspection reports and your due dates for both the API 510 programme and the TSSA certificate.
2. Procedures. NDE procedures prepared or reviewed by an ASNT NDT Level III, with coverage plans where on-stream inspection is proposed in place of entry.
3. Field work. Crews mobilised to your site; the schedule is agreed during scoping around unit status, permits, confined-space entry and weather.
4. Data QA. Readings are checked against history on site; questionable readings are flagged to the inspector immediately and re-shot while the vessel is open.
5. Digital report. CML IDs, readings, C-scans, indication tables, photographs, calibration records, procedures and technician certifications, delivered through Atlantis's reporting platform.
6. Evaluation and sign-off. The inspector evaluates the results, sets corrosion rates, remaining life and the next interval, and signs. We can calculate corrosion rates and remaining life from our data for the inspector's review, but the interval is the inspector's and owner's decision. Atlantis performs the NDE; your API 510 Authorized Inspector remains inspector of record and signs the inspection report.
7. Next cycle. CML numbering and data carry forward, so the next survey trends cleanly.

Service detail: API 510 pressure vessel NDE support and pressure vessel inspection services. Need the scope priced? Get a quote within 24 hours.

Ontario regulations that sit on top of API 510

Direct answer: The Technical Standards and Safety Act, O. Reg. 220/01 and TSSA's Boilers and Pressure Vessels Code Adoption Document govern Ontario vessels. They require a current Certificate of Inspection, periodic inspection by TSSA or the insurer at set maximum intervals, design registration under CSA B51, and TSSA control of repairs and alterations. Confirm current requirements with TSSA.

Certificate of Inspection. Under O. Reg. 220/01, a regulated boiler or pressure vessel may not be operated without a current Certificate of Inspection issued by TSSA. After a periodic inspection, the inspector issues a Record of Inspection, and the owner applies through TSSA's BPV Portal to renew the certificate within 30 days of receiving it.

Periodic inspection intervals. The Code Adoption Document sets maximum intervals by equipment type. The current amendment, BPV-25-01 Revision 1, published 15 May 2026 and effective 15 June 2026, keeps the general pressure vessel interval at a maximum of three years, with shorter intervals for some equipment such as deaerators and vessels with quick-opening doors, and exempts a few classes such as small compressed-air receivers within stated limits. The periodic inspection may include internal and external inspection and testing of safety devices as the inspector directs. Note what this means for API 510 owners: whatever interval API 510 or an RBI study would allow, the jurisdictional periodic inspection still comes round at least every three years for a general process vessel.

Who inspects. TSSA inspects uninsured equipment; for equipment covered by boiler and machinery insurance, the insurer is responsible for the periodic inspection and may retain a third-party inspection provider holding a TSSA certificate of authorization. In-service inspections must be performed by persons holding a valid Ontario Certificate of Competency, which requires passing TSSA's own examination and the National Board in-service commission examination. Inspection reports must be kept for six years.

Owner-user self-inspection of repairs. Ontario does not hand periodic certification to owners the way Alberta does. What TSSA does offer is accreditation of an owner-user self-inspection repair programme, modelled on the National Board's owner-user accreditation, which lets qualified owner-user inspectors accept specified repairs at an accredited location without the TSSA inspector or insurer being present. That programme sits alongside the owner's API 510 work and does not replace the periodic inspection.

Construction, registration and codes. The 2026 Code Adoption Document adopts CSA B51-24, which calls up ASME Section VIII for vessels and requires design registration with a Canadian Registration Number (CRN). The National Board Inspection Code is adopted as well, with CSA B51 prevailing where the two conflict and the NBIC used as a guide for repair and alteration procedures. See TSSA compliance for inspection providers, CSA B51, CRN registration and NBIC (NB-23).

NDE personnel. The Code Adoption Document lists both CAN/CGSB-48.9712 (ISO 9712) and ASNT SNT-TC-1A among its adopted references and amends CSA B51 to accept SNT-TC-1A as a standard for NDE personnel on code work. For in-service examinations the owner and the inspector decide which certification scheme they require. Atlantis technicians are certified under ASNT SNT-TC-1A with ASNT Level III oversight. The Canadian General Standards Board, which published CAN/CGSB-48.9712, closed on 1 April 2026; Natural Resources Canada's NDT Certification Body continues to certify to that standard, so confirm the current certification body if your programme requires the Canadian scheme. Background: CAN/CGSB-48.9712 and NRCan NDT certification.

Other overlays. Pipelines entering Sarnia's refineries are regulated by the Canada Energy Regulator where they cross provincial or national borders and by the Ontario Energy Board and TSSA for provincially regulated lines; liquid fuels storage sits under TSSA's Fuels Safety Program. Occupational health and safety rules under the Occupational Health and Safety Act govern confined-space entry for internal inspections.

Planning around turnarounds, winter and the TSSA cycle

Direct answer: Line up three calendars: the API 510 due dates in your inspection plan, TSSA certificate expiry dates, and your turnaround schedule. Book Sarnia and Nanticoke turnaround NDE well ahead, plan external and CUI work outside deep winter, and use on-stream techniques to fill gaps between outages.

• Certificate expiry drives the floor. Because the general pressure vessel certificate cycle is three years at most, owners with longer API 510 intervals still need a periodic inspection on time. A well-planned on-stream UT and external programme can support the jurisdictional inspection between internal inspections.
• Turnaround crunch. Sarnia's refineries and chemical plants often schedule major outages in spring and autumn, and contractors compete for the same weeks. Scope heavy-wall TOFD, reactor PAUT and WFMT of sour and amine vessels early.
• Winter work. Cold reduces couplant performance, battery life and personnel endurance; heated hoarding may be needed for external work, and insulation removal is best done in milder months to avoid wetting what you uncover.
• On-stream as a substitute for entry. Where the plan proposes on-stream inspection instead of an internal, agree technique, coverage and acceptance criteria with the inspector before mobilisation, and record what was not covered.
• High-temperature surveys. Readings on hot vessels need temperature-rated probes and couplant and temperature correction, which we document in the report.
• Insurer coordination. If your equipment is insured, invite the insurer's inspector to review NDE results during the outage so the Record of Inspection can be issued without a second visit.

API 510 inspection support across Ontario

Direct answer: Atlantis supports vessel NDE from Sarnia and the Lake Erie shore to the Golden Horseshoe, eastern Ontario and the north. Crews are mobilised to your site and the schedule is agreed during scoping; Atlantis has no local office in Ontario.

• Sarnia, Corunna and Courtright: refinery, petrochemical, fertilizer and specialty chemical vessels; see NDT consulting in Sarnia and inspection ERP for Sarnia contractors.
• Nanticoke and Haldimand County: refinery and steel-works vessels; see inspection ERP for Nanticoke.
• Hamilton and Burlington: steel-mill gas receivers, deaerators and process vessels; see a digital twin for Hamilton assets.
• Toronto, Mississauga, Oakville and Whitby: chemical, pharmaceutical and food-processing reactors, autoclaves and receivers; see ultrasonic testing in Toronto and PAUT inspection in Toronto.
• Windsor and the southwest: automotive, chemical and ethanol plants; see practical NDT in Windsor.
• Ottawa, Kingston and Cornwall: chemical, institutional and industrial steam and process vessels; see practical NDT in Ottawa.
• Sudbury, Timmins and Thunder Bay: smelter, mine-site and pulp and paper vessels.

Sibling hubs for the province: API 653 tank inspection in Ontario and API 570 piping inspection in Ontario. For written practices, procedures and Level III support, see NDT consulting in Ontario and NDT consulting across Canada; for ASNT technician training, NDT training in Ontario; for inspection-management software, NDT ERP for Ontario inspection companies; for hands-on practice, practical NDT in Ontario; and for asset visualisation, digital twins in Ontario.

Building a record TSSA, your insurer and your API 510 inspector can all use

Direct answer: One NDE data set should serve three readers: the API 510 inspector who trends CMLs, the jurisdictional inspector who issues the Record of Inspection, and auditors who check that the method suited the damage. Atlantis structures each report so all three find what they need without a second survey.

Ontario owners often keep two parallel records: the API 510 programme in an inspection database and the TSSA certificate history in the BPV Portal. The NDE report is where they meet. Each vessel section in our reports identifies the TSSA unique identifier and owner tag, the damage mechanism and morphology the examination targeted, the CMLs measured and the coverage achieved, and the readings with minimum, average and previous values. Procedures, calibration certificates, probe data and technician certification records are attached so the inspector can verify qualifications. Questionable readings are listed separately, with what was done to resolve them. Areas not examined are listed with the reason.

That structure makes the next cycle cheaper and the trend more reliable. It also makes it easy to answer an auditor's or an insurer's question about whether a survey could actually find the damage being managed. Results can be tracked against due dates in our inspection-management ERP, mapped onto a digital twin, or delivered in the formats shown on NDT report templates. Book a scoping call for your next Ontario turnaround.

What to send us for an Ontario quote

Direct answer: Send the vessel list with TSSA identifiers and CRNs, the inspection plan and CML maps, the last inspection reports, certificate expiry dates, your examiner certification requirements, access and cleaning status, and target dates. We quote within 24 hours of receiving that information.

1. Vessel tags, TSSA identifiers, CRNs, data reports, drawings and materials of construction.
2. The last internal, on-stream and external inspection reports and thickness history.
3. The inspection plan or CML map, damage mechanisms and API 510 due dates.
4. Certificate of Inspection expiry dates and whether the equipment is insured.
5. Your certification requirements by method (SNT-TC-1A or the Canadian scheme).
6. Inspection type, entry and cleaning status, insulation and scaffold requirements.
7. Dates, outage window and site orientation requirements.

Send us your vessel list and we will come back with questions or a draft scope.

Frequently asked questions: API 510 in Ontario

Is API 510 required by law in Ontario?

Not by name. O. Reg. 220/01 and TSSA's Code Adoption Document require periodic inspection and a current Certificate of Inspection, and adopt CSA B51 and the NBIC. Refineries and chemical plants use API 510 as their in-service inspection code on top of that. Confirm specific obligations with TSSA.

How often must a pressure vessel be inspected in Ontario?

Under the current Code Adoption Document, a general pressure vessel must be periodically inspected at a maximum interval of three years, with shorter intervals for some equipment such as deaerators and quick-opening-door vessels. API 510 intervals may be longer, but the jurisdictional cycle still applies.

Who can sign a pressure vessel inspection in Ontario?

The periodic inspection is done by a TSSA inspector for uninsured equipment or by the insurer's inspector for insured equipment, holding an Ontario Certificate of Competency. The owner's API 510 inspector manages the in-house programme. Atlantis does neither; we perform the NDE.

What is a TSSA Certificate of Inspection?

It is the document that allows a regulated boiler or pressure vessel to operate in Ontario. After a passed periodic inspection, the inspector issues a Record of Inspection and the owner renews the certificate through TSSA's portal within 30 days.

Does Atlantis supply TSSA-certified or API 510 inspectors?

No. We are not an Authorized Inspection Agency, we do not supply API-certified inspectors or Ontario Certificate of Competency holders, and we do not certify vessels. We supply NDE data to the inspector who does.

Are your technicians CGSB certified?

Atlantis technicians are certified under ASNT SNT-TC-1A with Level III oversight. TSSA's adopted references include SNT-TC-1A, but the owner and inspector decide which scheme they require for in-service work. If you need CAN/CGSB-48.9712 certification, tell us during scoping and we will confirm what we can staff.

Can on-stream inspection replace an internal inspection in Ontario?

API 510 allows on-stream inspection in place of an internal where its conditions are met and the inspector agrees the NDE can detect the expected damage. The TSSA periodic inspection still has to happen on schedule, so agree the approach with both inspectors.

Who licenses industrial radiography in Ontario?

The Canadian Nuclear Safety Commission, federally. Exposure devices are licensed by the CNSC and operated by CNSC-certified exposure device operators, so RT is done only by crews holding those licences and certifications.

Do you perform RBI or fitness-for-service assessments?

No. Those are performed by the owner's engineers or a specialist. We supply the thickness data, corrosion maps and flaw sizes they use, in a format that drops into their models.

Do you offer API 510 or Ontario inspector certification training?

No. Atlantis trains to ASNT SNT-TC-1A only. See the API inspector career guide for the API route and NDT training in Ontario for ASNT NDE skills.

How quickly can you mobilise to Sarnia or Nanticoke?

We quote within 24 hours of receiving the scope; the mobilisation date is agreed during scoping around your outage, permits and site orientation.

Do you work on nuclear pressure-retaining components?

Nuclear pressure boundary work in Ontario follows CSA N285 programmes with their own qualification requirements, which this page does not cover. Ask us about conventional balance-of-plant vessels at generating stations.

Next step

To line up NDE that serves your API 510 programme and your TSSA certificate cycle at the same time, send us your Ontario scope. Atlantis performs the NDE; your API 510 Authorized Inspector remains inspector of record and signs the inspection report, and the TSSA or insurer's inspector issues the Record of Inspection.

More Atlantis NDT services in Ontario

• NDT training and certification in Ontario
• Level III consulting in Ontario
• API 653 storage tank inspection support in Ontario
• API 570 piping inspection support in Ontario
• NDT ERP software in Ontario
• Practical NDT simulator in Ontario

Part of the full range of pressure vessel inspection services from Atlantis NDT.