Combustion Engineering Resources & Technical Guides

Technical articles, code compliance guides, and engineering insights from Complete Combustion – Ontario’s P.Eng-stamped industrial combustion engineering practice. This page is a working reference for the professional credentials behind our designs and the codes and standards that shape every combustion engineering package we issue.

Professional Engineering & Certificate of Authorization

Every design package we issue is reviewed and stamped by a licensed Professional Engineer under a Professional Engineers Ontario Certificate of Authorization. That means the calculations, drawings, and code compliance behind your fuel train, burner management system, or furnace design carry real professional and legal accountability, not just an engineering opinion.

A Certificate of Authorization is what allows an engineering practice to offer professional engineering services to the public in Ontario. It sits alongside the individual P.Eng license: the license certifies an engineer’s competence and standing, while the Certificate of Authorization certifies that the firm itself is structured and insured appropriately to take on that professional liability. For fuel-burning equipment specifically, TSSA and most other Authorities Having Jurisdiction require this combination before they will accept a design submission at all. Without it, a design package is effectively a starting point for someone else’s engineering review rather than an approvable document in its own right.

In practice, this shapes how we work. Every drawing set, calculation package, and cause-and-effect matrix we produce is reviewed against the applicable codes before it is stamped, not after a reviewer flags a gap. That review covers the full scope of a project, not just the headline burner selection: fuel train configuration, structural and thermal calculations, electrical and control system design, and the safety interlock logic that ties it all together.

Why Compliance-First Engineering Matters

Combustion systems sit at the intersection of several overlapping codes, and a missed requirement rarely surfaces until a TSSA reviewer or field inspector catches it, by which point it’s a schedule and cost problem, not just a paperwork one. A fuel train that looks complete on a P&ID can still be missing a required proof-of-closure switch for its input rating. A furnace design that hits its temperature and throughput targets can still fall short of NFPA 86’s ventilation or explosion protection requirements for the atmosphere involved. A control panel that satisfies the electrical code can still be wired in a way that violates the fail-safe logic a burner management system depends on.

None of these are exotic failure modes. They are the ordinary, recurring gaps that show up when a design is built to a general specification and checked against code afterward, rather than designed to the applicable code set from the first drawing. We treat the full stack of applicable codes and standards as an input to the design process, not a checklist applied at the end, which is why our packages are built to move through TSSA review and field inspection with as few comment cycles as possible.

The Codes and Standards We Design To

The list below isn’t exhaustive for every project, since the applicable code set depends on fuel type, equipment classification, and jurisdiction. But these are the standards that shape the majority of the industrial combustion, furnace, and burner management work we do.

TSSA & the Ontario Regulatory Framework

The Technical Standards and Safety Authority (TSSA) is the regulatory body responsible for fuel-burning equipment safety in Ontario. Most new industrial combustion installations, and many retrofits, require a TSSA Field Approval before the equipment can be put into service. That approval process reviews the engineering package against the applicable codes, confirms the equipment and installation match what was submitted, and results in a field inspection before final sign-off.

Because TSSA review sits downstream of the engineering design, the completeness and clarity of the submitted package has an outsized effect on how quickly approval moves. A package that clearly demonstrates code compliance, with calculations and drawings rather than assertions, tends to move through review with fewer comment cycles than one that leaves gaps for a reviewer to identify.

CSA B149.1 & B149.2 — Natural Gas and Propane Installation Codes

CSA B149.1 governs natural gas installations across Canada, and CSA B149.2 governs propane installations. Together they set the baseline requirements for venting, clearances to combustible materials, appliance connections, and fuel piping for gas-fired equipment generally. For industrial applications, these codes typically work alongside CSA B149.3 rather than in place of it, since B149.1 and B149.2 are written primarily around appliance-level installations.

CSA B149.3 — Industrial and Commercial Gas-Fired Equipment

CSA B149.3 is the code most directly relevant to the custom industrial combustion systems we design: fuel trains, burners, and combustion equipment that falls outside standard packaged appliances. It sets requirements for fuel train configuration, safety shutoff valve arrangements, purge sequencing, and the pressure switches and interlocks that supervise a system before and during operation. For higher input ratings, it requires redundant safety shutoff valves with proof-of-closure supervision, precisely the kind of requirement that’s straightforward to design in from the start and expensive to retrofit after a reviewer flags it.

NFPA 86 — Ovens and Furnaces

NFPA 86 is the standard most industrial furnace, oven, and dryer combustion systems are designed against, particularly where explosion protection, atmosphere control, or high-temperature processes are involved. It classifies equipment into categories (Class A through D) based on what’s being processed and what atmosphere is present, and sets requirements for purge timing, safety ventilation rates, and excess temperature limit controls specific to each classification. A design that doesn’t correctly classify the equipment early on can end up missing the interlocks that classification requires.

ASME B31.3 — Process Piping

ASME B31.3 sets design, material, and fabrication requirements for pressure piping systems, and it comes into play on combustion projects wherever fuel or process piping falls outside the scope of the gas codes alone, such as higher-pressure fuel supply piping or piping carrying other process fluids integrated with the combustion system. It governs wall thickness calculations, allowable stresses, and joint design based on the piping’s pressure and temperature service.

Ontario Electrical Safety Code (ESA SPE-1000)

The Ontario Electrical Safety Code governs the electrical design and installation requirements that apply to every burner management system and control panel we design: wiring methods, grounding and bonding, and hazardous location classification where combustible atmospheres or dusts are present. Because a burner management system’s safety logic depends on correct, fail-safe electrical design, electrical code compliance isn’t a separate concern from combustion safety, it’s part of the same design problem.

How These Codes Interact on a Real Project

Few projects sit under a single code in isolation. A typical industrial furnace retrofit might need to satisfy CSA B149.3 for the fuel train, NFPA 86 for the furnace’s explosion protection and atmosphere control, ASME B31.3 for any higher-pressure process piping, and the Ontario Electrical Safety Code for the burner management system’s electrical design, all reviewed by TSSA as part of a single Field Approval submission. Designing each requirement in isolation, then reconciling conflicts afterward, is a slower and more error-prone way to get to an approvable package than starting from the full applicable code set.

Our Engineering Review Process

Code compliance isn’t a single step at the end of a project, it’s built into how each stage of the work gets done:

1. Scope & code identification. Before any drawing work starts, we confirm the fuel type, equipment classification, and applicable code set for the specific installation and jurisdiction. This determines which of CSA B149.1/.2/.3, NFPA 86, ASME B31.3, and the electrical code actually govern the project.
2. Calculations & preliminary design. Mass and energy balance, fuel train sizing, and structural or thermal calculations are developed against the code requirements identified in step one, not against a generic specification.
3. Drawing package & cause-and-effect matrix. P&IDs, electrical schematics, and the safety interlock logic are documented in a form a fabricator can build from and a TSSA reviewer can verify against the code.
4. P.Eng review & stamping. The complete package is reviewed against the applicable codes and stamped under our Certificate of Authorization before it’s issued.
5. TSSA submission support. Where a Field Approval is required, we support the submission and respond to any reviewer comments as the engineer of record.
6. Field support through commissioning. Questions that come up during fabrication, installation, or commissioning get resolved by the same engineering team that produced the design, not handed off to someone unfamiliar with the project.

Frequently Asked Questions

Do I need TSSA approval for a retrofit, or only for new installations?

Many retrofits require a new or updated TSSA Field Approval, particularly if the fuel train, burner, or control system is being changed rather than simply repaired like-for-like. Whether a specific retrofit triggers a new approval depends on the scope of what’s changing and the equipment’s original approval status, which is worth confirming early rather than assuming a retrofit is exempt.

What’s the difference between a P.Eng license and a Certificate of Authorization?

A P.Eng license certifies an individual engineer’s competence and standing to practice professional engineering in Ontario. A Certificate of Authorization is issued to the firm, and it’s what permits that firm to offer professional engineering services to the public. Both are required together for a design package to be accepted by TSSA and most other regulatory bodies; an individual P.Eng license on its own isn’t sufficient for a firm to issue stamped drawings commercially.

Which code applies if my project involves both gas fuel train work and process piping?

It’s common for a single project to fall under more than one code at once. CSA B149.3 typically governs the gas fuel train itself, while ASME B31.3 may apply to higher-pressure process piping integrated with the same system. Rather than designing each in isolation, we identify the full applicable code set at the scoping stage so the piping and fuel train design are coordinated from the start.

How long does TSSA review typically take once a package is submitted?

Review timelines vary with submission volume and how complete the package is on first submission; there’s no fixed turnaround TSSA guarantees. A complete, well-documented submission that clearly demonstrates code compliance, rather than one that requires the reviewer to request missing calculations or drawings, is the biggest factor within an engineering firm’s control for keeping that timeline as short as possible.

Can I use my own fabricator or installer with a P.Eng-stamped design package?

Yes. Because our practice is design-only, the stamped engineering package is built to be construction-ready for any qualified fabricator or installer you choose, rather than tied to a specific contractor.

TSSA & Codes Compliance Guides

For a deeper look at how specific code requirements apply in practice, these guides walk through real design scenarios:

• Industrial Combustion Engineering in Ontario — P.Eng Stamped Design from Brampton
• Industrial Burner Retrofit Engineering — When to Retrofit and What the Package Includes
• NFPA 86 Pre-Purge Calculations for Industrial Furnaces and Ovens — Engineering Guide
• CSA B149.3 Fuel Train Design Requirements for Industrial Combustion Systems in Canada
• What a TSSA Field Approval Combustion Package Must Include — Ontario P.Eng Guide

Our Engineering Services

Each of the codes above shows up in a specific part of the engineering package we deliver:

• P&ID & Combustion Schematics
• Thermal Process & Combustion System Design
• Fuel Train & Valve Train Piping Design
• Fuel Storage System Design
• Burner Management & Electrical Integration
• PLC Automation & Process Logic

If you’re planning a new installation or a retrofit and want to understand which codes apply to your specific equipment and jurisdiction before committing to a design direction, that’s exactly the kind of question worth raising early.

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