Complete Guide to Welding Codes: AWS, ASME & More

Welding codes aren’t paperwork theatre. They’re your operating system for risk.

For many fabrication teams, welding codes only show up when a customer drops a contract on the desk and someone notices a line that changes the whole job: AWS D1.1, D1.2, D1.6, D17.1, ASME Section IX, B31.3 and suddenly the work is no longer “just welding”.

That’s usually when frustration kicks in. Production teams see delay. Quality sees exposure. Management sees cost. And everyone wonders the same thing: which code applies, how strict is it, and what’s actually different in practice?

The video, featuring welding engineer Joel Eiffel and code specialist Logan of Couser Engineering, is useful because it doesn’t treat welding codes as abstract compliance documents. It frames them for what they really are: different rule sets for different failure consequences.

That distinction matters. A code for a building frame is not trying to solve the same problem as a code for a titanium aerospace assembly or a pressure-containing chemical line. If you use the wrong mental model, you create rework, inspection disputes, qualification delays, or worse, false confidence.

This article turns that discussion into a practical guide for production managers, quality engineers and operations leaders who need to make faster, better decisions on the shop floor.

Key Takeaways

• Start with service condition, not material alone. Steel does not automatically mean AWS D1.1; pressure service, corrosion, or aerospace requirements can point elsewhere.
• D1.1 is the default structural steel code in many US applications, but it is primarily about load-bearing structures, not pressure containment.
• D1.2 for aluminium has a higher barrier to entry because it does not allow prequalified procedures; expect more upfront qualification cost and time.
• D1.6 matters when corrosion resistance is part of the job, especially for stainless structures and some dissimilar metal welds.
• D17.1 is aerospace-focused and quality-intensive in production, especially where volumetric inspection is required, but it relies heavily on engineering authority.
• ASME is best understood as an ecosystem, not one book: materials, welding qualification, NDE and construction requirements are spread across linked sections.
• Inspection strategy is a major differentiator between codes. Don’t assume the presence of acceptance criteria means an inspection method is mandatory.
• If a contract names a code, verify the documentation burden immediately: WPS, PQR, welder qualifications, traceability, inspection method, revision level and any overlay specs.
• For managers, bad culture costs more than hard rules. Most audit failures come less from technical impossibility than from inconsistent discipline.
• Action point: Build a one-page internal “code triage” checklist so estimating, quality and production assess code impact before accepting the job.

Don’t want to work it out from a video transcript? GoSmarter’s free Welding Code Selector answers four questions about the job and returns the code, the prequalification stance, and a documentation checklist in under a minute.

The big idea: codes reflect consequence

One of the strongest themes in the discussion is that welding codes are not competing versions of the same thing. They exist because industries face different risks.

A structural frame in a building must safely carry load. A stainless support in a corrosive or inaccessible environment must resist degradation over time. A rocket or aircraft weld may be weight-critical and subject to extreme service conditions. A pressure vessel or process line must not fail under internal pressure.

That leads to a simple but powerful rule:

Ask these three questions before you ask which code applies

1. What is the weld doing?
   Carrying structural load, containing pressure, resisting corrosion, or meeting flight-critical performance?

2. What happens if it fails?
   Cosmetic issue, production downtime, environmental incident, loss of asset, or risk to life?

3. What level of proof is required?
   Visual inspection only, sample radiography, full volumetric inspection, or extensive traceability?

For younger operations and quality leaders, this is the fastest way to cut through the noise. Don’t start with the thickness table or filler classification. Start with failure mode and business consequence.

AWS D1.1: the structural steel heavyweight

If your world is platforms, mezzanines, heavy fabrications, supports, frames and general steel structures, AWS D1.1 is often the first code in the conversation.

In the video, it’s described as the most common structural welding code many people encounter. That fits its reputation: large, well-established, and widely treated as the benchmark others get compared to.

Where D1.1 fits well

D1.1 is fundamentally about structural steelwork. Think:

• buildings
• support frames
• girders
• large steel members
• structural tubular sections that carry load rather than fluids

The key distinction raised in the discussion is important: tubular members in D1.1 are structural, not process piping. If the tube exists to support stress, D1.1 may fit. If it exists to move product under service conditions, you may be in a different code family entirely.

Why fabricators like it

A major practical advantage is prequalification. For common joints, materials and processes, you may not need to run a full PQR. That matters because PQRs cost money, consume machine time, use qualified personnel and often slow job launch.

For a production manager, that means D1.1 can be relatively efficient when the job falls within the guardrails:

• recognised joint design
• recognised material grouping
• approved process window
• appropriate thickness range

That is one reason D1.1 is so common in mainstream heavy fabrication.

Where people get tripped up

The video calls out a misunderstanding that causes real-world friction: inspection criteria and inspection requirement are not the same thing.

D1.1 includes acceptance criteria for methods such as:

• MT
• UT
• RT

But, as discussed, the code does not automatically require those methods for all production welds. The baseline requirement is visual inspection. If design teams or buyers assume that because RT criteria exist, RT must be happening in production, disputes follow.

This is a classic handover failure between design intent and fabrication execution.

Operational implication

If you’re quoting or launching D1.1 work, do not stop at “built to D1.1”. Clarify:

• Is visual inspection the only mandatory production inspection?
• Has the client contract added UT or RT?
• Is there any project-specific requirement beyond the code?
• Are there fracture-critical details not covered by default assumptions?

That conversation protects both schedule and margin.

AWS D1.2: aluminium structure, no shortcuts

If D1.1 is forgiving in familiar territory, AWS D1.2 is not.

The standout point from the video is this: there is no prequalification route in D1.2. If you are welding aluminium structural work under this code, you should expect to qualify procedures.

Why that changes the commercial picture

For estimators and ops leaders, no prequalification means:

• more up-front cost
• longer lead time before production
• more destructive testing
• greater exposure if the job was under-scoped

That can be painful for shops that “do aluminium all the time” informally but have not built the document discipline the contract actually requires.

Why aluminium is harder in practice

The speakers point out that aluminium already tends to be more demanding than structural carbon steel. Even without adding outside detail, the practical message is clear: the code’s barrier is higher because the welding challenge is higher.

This is the part many teams underestimate. They assume shop familiarity equals qualification readiness. It doesn’t.

A team can be competent at making acceptable aluminium fabrications for general use and still be nowhere near ready for contract work invoking D1.2.

Where D1.2 tends to appear

Based on the video, likely applications include:

• marine structures
• specialist support tooling
• structural aluminium assemblies where weight or corrosion resistance matters

For a steel-industry audience, the strategic lesson is straightforward: if your shop wants to move into aluminium structural work, treat code readiness as a capability build, not as a simple material extension.

AWS D1.6: when stainless changes the rules

Shops that are excellent with carbon steel often underestimate what happens when the material changes to stainless. The video’s discussion on AWS D1.6 is a useful reality check.

D1.6 is about structural stainless, not “steel but shinier”

The code applies where the structure itself is stainless steel, often because the environment demands corrosion resistance or long-term durability.

Examples mentioned in the discussion include:

• structures in corrosive settings
• inaccessible service areas
• nuclear-related supports
• stainless attachments or dissimilar metal welds in otherwise carbon-steel assemblies

The real issue is contamination control

The most valuable point here is not code citation; it’s fabrication behaviour.

Moving from carbon steel to stainless means small habits become expensive defects:

• using the wrong wire brush
• sharing abrasives between carbon and stainless work
• poor segregation of tools and work areas
• failing to manage post-weld surface condition

This is where old-school “we’ve always done it this way” can quietly destroy quality. Stainless may look fine leaving the bay and then show corrosion later because iron contamination was embedded into the surface.

For millennial and Gen Z production leaders trying to modernise shop discipline, this is a cultural opportunity. Not every quality problem needs a new software platform. Sometimes it needs better process control of tools, consumables and work segregation.

Passivation is often misunderstood

The speakers also discuss passivation and distinguish it from chromium depletion issues around weld heat effects. Their core point is worth carrying forward: stainless performance depends on preserving or restoring the right surface condition, and not all post-weld treatments solve the same problem.

That matters commercially because customers often specify “stainless” expecting corrosion resistance, not just a stainless purchase order line. If the process undermines the surface, the value of the material upgrade is partly lost.

AWS D17.1: aerospace quality and the price of certainty

The discussion becomes especially interesting at AWS D17.1, because the speakers move beyond summary and into critique.

First, it’s not the same kind of document as the others

One speaker makes a key distinction: D17.1 is treated as a specification that must be invoked, rather than a legally mandated code in the same sense as certain other frameworks. Whether or not a reader agrees with the formal phrasing, the practical point is what matters:

Aerospace quality often sits inside a layered contractual system, not just one standalone rulebook.

That means D17.1 may be only the starting point. Prime contractors often add overlay requirements, and internal engineering authority has a larger role.

What makes D17.1 feel different on the shop floor

The video positions D17.1 as high quality chiefly because of inspection intensity and traceability expectations, especially for critical weld classes.

The broad production message is:

• procedure qualification may not be the hardest part
• production acceptance can be far stricter
• welder skill is exposed because volumetric inspection catches what visual inspection won’t

That is a major mindset shift for shops used to less intensive NDE. In aerospace-style work, quality is not a final gate. It is the product.

Why younger leaders should care, even outside aerospace

Most steel and metals operations won’t become aerospace suppliers. But D17.1 still offers a useful model for modern manufacturing:

• high traceability
• precise filler control
• strong linkage between welder, consumable and weld record
• internal NDE capability where the volume justifies it
• rapid feedback loops from inspection to process correction

Those disciplines are not only for rockets. They are exactly the kinds of systems that improve scrap, repeatability and customer confidence in any high-consequence fabrication environment.

The trade-off: flexibility versus standardisation

The speakers point out that D17.1 often leaves more to engineering authority than ASME does. That creates flexibility, but also unevenness. Large organisations with deep historical data can operate effectively in that environment. Start-ups or immature supply chains may struggle.

That insight goes beyond welding. It’s a reminder that some standards assume organisational maturity. If your company lacks the engineering bench, data history or process discipline, a more prescriptive code may actually reduce risk.

ASME: less a codebook, more an ecosystem

If D17.1 represents flexibility inside a demanding quality environment, ASME is presented in the video as the opposite strength: a broad, highly structured system with many of the answers already defined.

That is why one speaker calls it an ecosystem rather than a single code.

What that means in practice

Under ASME, requirements are spread across linked sections covering areas such as:

• materials
• welding qualification
• NDE methods
• construction rules

The video references examples including Section II, Section V, Section IX, B31.3 and Section VIII. The exact route depends on what you are building, but the point is consistent: pressure-containing work lives in a more codified framework.

Why many engineers prefer it

The appeal is simple: less ambiguity.

Compared with a system that pushes decisions back onto engineering authority, ASME can be more explicit about:

• material properties
• qualification rules
• inspection methods
• acceptance criteria
• design or construction context

For teams scaling operations, that can be a huge advantage. Clearer rules mean fewer arguments, faster onboarding and less dependence on tribal knowledge.

Keeping D1.1, D1.2, D1.6, D17.1, ASME and the rest straight across a mixed order book is its own job. GoSmarter’s Standards Library puts 14 welding and structural codes on one filterable page, with scope, default inspection expectations and links to the publisher source for each.

Where ASME shows up

The discussion places ASME in sectors such as:

• refineries
• power generation
• chemical process facilities
• desalination
• pressure vessels
• piping systems
• nuclear pressure-containing applications

For steel-industry leaders, the practical translation is: if the part contains pressure, expect a different level of documentation and discipline than standard structural work.

Why this matters commercially

Pressure jobs can look deceptively similar to non-pressure jobs in the bay. The geometry may feel familiar. The weld process may be familiar. But the compliance burden is not.

If your commercial team prices a pressure job like standard fabrication, margin evaporates fast through:

• qualification work
• added inspection
• documentation hours
• revision control
• client review cycles
• hold points

This is where better front-end code literacy directly protects EBITDA.

The most overlooked issue: inspection philosophy

If there is one concept worth lifting from the whole discussion, it is this:

Not all quality systems prove quality in the same way

Some frameworks put more burden on qualification. Others put more burden on production inspection. Others rely more heavily on engineering authority and traceability. Some require only visual inspection by default; others demand much more.

That means managers should stop asking only, “What code is it?” and start asking:

• What proof model does this code rely on?
• Where will the cost hit: pre-production, production, or audit trail?
• Do we have in-house capability, or will we outsource and wait?

This is not academic. It affects:

• quote accuracy
• lead time reliability
• labour planning
• rework risk
• customer confidence

Audits, quality systems and the culture problem

The video also branches into quality systems such as ISO 9001, AS9100D and NADCAP, particularly in the aerospace context. Even if your facility never sees a NADCAP auditor, the wider lesson applies.

Documentation is not the point. Repeatability is.

The speakers make a useful argument: auditors are not there to play “gotcha”. They are there to confirm that what the company claims to do is what it actually does.

That distinction matters because many plants still treat quality as overhead rather than as a production control mechanism.

When teams say:

• “Jim always does it right”
• “we’ve never had a problem before”
• “we’ll sort the paperwork later”

they are not describing a reliable system. They are describing fragility disguised as experience.

For modern operations leaders, culture beats heroics

The strongest line of thinking in the video is that technical issues are often fixable, but poor quality culture is harder to repair.

That should resonate in metals and steel manufacturing right now. Many teams are trying to run sophisticated production with:

• ageing work instructions
• fragmented data
• paper-heavy traceability
• inconsistent revision control
• too much reliance on a few veterans

The result is avoidable chaos.

A code-compliant shop is not necessarily a digitally advanced shop. But if your systems are ancient and clunky, code work exposes every weakness faster:

• wrong revision on the floor
• uncertain consumable traceability
• missing qualification records
• no clean audit path
• outsourced NDE bottlenecks
• hidden cost in manual admin

For Gen Z and millennial leaders, this is the bridge between quality and operational tech. Better systems are not about jargon; they are about removing friction from compliance.

A practical decision framework for fabrication teams

Instead of memorising every clause, use this short framework when a new coded job appears.

1. Define the function of the weld

Is it:

• structural load-bearing?
• pressure-containing?
• corrosion-critical?
• aerospace or flight-related?
• non-critical support hardware?

2. Confirm the governing document

Do not rely on assumptions. Check:

• contract
• drawing notes
• project specification
• customer overlays
• revision level

3. Identify qualification burden early

Ask immediately:

• Are procedures prequalified?
• Do we need a PQR?
• Do welder qualifications already cover this?
• Is dissimilar metal welding involved?
• Are client-specific tests added?

4. Map the inspection requirement

Separate:

• what the code allows
• what the code requires
• what the client adds

5. Check traceability capability

Can your current system track:

• WPS revision used
• welder identity
• filler/consumable batch
• inspection results
• hold point sign-offs

6. Price the administration honestly

Many coded jobs are won or lost in admin effort, not arc time.

What this means for decision-makers

For senior decision-makers focused on margin, scrap and compliance, the lesson is not simply “follow the code”. It is:

The wrong code decision creates hidden factory costs

These show up as:

• delayed first-article approval
• failed audits
• requalification
• scrap from incorrect procedure use
• customer disputes over inspection scope
• expensive outsourced NDE
• blocked shipments due to missing records

In a market where sustainability reporting and border-related compliance pressures such as CBAM are already adding administrative load, the last thing a metals business needs is avoidable welding-code confusion.

A cleaner code-selection and qualification process helps with:

• margin protection
• lower scrap and rework
• more reliable delivery
• stronger customer trust
• better use of skilled labour

That is not bureaucracy. That is margin protection.

Conclusion: the best code is the one that matches the risk

The video never lands on a universal winner, despite the friendly debate. That’s the right conclusion.

AWS D1.1 is strong for mainstream structural steel.
D1.2 raises the bar for aluminium structural work.
D1.6 matters when stainless service conditions change the fabrication rules.
D17.1 pushes inspection, traceability and engineering authority in aerospace contexts.
ASME provides a more tightly structured route for pressure-containing systems.

The bigger lesson is this: welding codes are not there to slow production down. They exist to make sure the level of proof matches the level of consequence.

For modern fabrication teams, that creates a competitive advantage. If you can identify the right code early, understand the proof model, and build systems that remove compliance friction, you move faster than shops still treating coded work as a last-minute paperwork problem.

And in today’s metals industry, speed with control is exactly what separates the shops that win good work from the shops that only chase it.

Go deeper

• Welding Code Selector — free tool, answer four questions and get the code, the rationale and a job checklist
• Standards Library — free, filterable reference for 14 welding and structural standards
• Compliance solutions — how GoSmarter’s quality engineers keep welder qualifications and traceability audit-ready

Source: “Welding Engineers Explain Welding Codes: AWS vs. ASME Battle!” - Donut Tools, YouTube, Aug 3, 2026 - https://www.youtube.com/watch?v=MZzilgLg00c