Inspection Standards & Codes
Industrial inspection requirements depend on the equipment, project specification and controlled technical documentation. Dilenza supports assignments involving welding, protective coatings and vendor inspection under internationally recognized standards and project-specific requirements.
The applicable code, edition, acceptance criteria and inspector responsibilities must always be confirmed from the project's controlled documentation.
- AWS
- ASME
- API
- ISO
- EN
- AMPP
- SSPC
- Client Specifications
Standards Define the Acceptance Criteria
A qualified inspector verifies that work meets the requirements defined by the applicable standard. Without the correct standard, inspection has no defined basis for acceptance or rejection.
Projects may operate under a single primary code, or under several codes depending on the equipment, process and jurisdiction involved.
The applicable standard, edition, addenda and acceptance level should come from the project specification, ITP, purchase order or other controlled documentation.
Where the requirement is not clear, Dilenza can review the available documentation and help confirm the applicable standards before an inspector is proposed.
Welding Standards and Codes
Welding inspection requirements can be governed by structural, pressure-equipment, pipeline, railway, marine or project-specific standards. Inspector selection therefore considers both the required qualification and practical experience with the standards applicable to the work. Common standards include:
- AWS D1.1
Structural welding code for steel, covering welder and WPS qualification, fabrication, inspection and acceptance criteria for structural steel welds.
Explore AWS D1.1 Welding Inspection Services ASME Section IX
Welding and brazing qualification requirements for pressure piping, pressure vessels and nuclear components under ASME Boiler and Pressure Vessel Code.
- API 1104
Welding of pipelines and related facilities, covering qualification, construction, inspection and acceptance of girth and groove welds.
Explore API 1104 Welding Inspection Services ISO 3834
Quality requirements for fusion welding of metallic materials, with the ISO 3834 series defining comprehensive, standard and elementary levels of welding quality requirements for workshop and field fabrication.
ISO 9606
Qualification testing of welders for fusion welding, defining how welder qualification is assessed across processes and material groups.
ISO 15614
Welding procedure qualification by testing, defining how a Welding Procedure Specification (WPS) is validated against standard test pieces and acceptance criteria.
ISO 5817
Quality levels for imperfections in fusion-welded joints, providing acceptance criteria by weld quality level for steel.
ISO 17637
Visual testing of fusion-welded joints in metallic materials, including visual examination before welding where applicable.
- EN 1090
Execution of steel and aluminium structures, covering conformity assessment, welding qualifications and factory production control.
Explore EN 1090 Welding Inspection Services - EN 15085
Welding of railway vehicles and components, defining welding performance levels, manufacturer certification and weld qualification for rail applications.
Explore EN 15085 Welding Inspection Services
Protective Coating Standards
Coating inspection requirements depend on the specified coating system, substrate, surface preparation, environmental conditions, application requirements and acceptance criteria. Common standards include:
ISO 12944
Paint systems for steel structures, defining environment categories, durability ranges and protective paint system selection.
ISO 8501
Visual assessment of surface cleanliness after abrasive blast cleaning, providing reference photographs for preparation grades.
ISO 8502
Tests for the assessment of surface cleanliness, covering soluble salt contamination, dust and moisture that affect coating adhesion.
ISO 8503
Surface roughness characteristics of blast-cleaned steel substrates, defining reference comparators and profile measurement.
ISO 19840
Measurement of dry film thickness on rough surfaces, defining methods and acceptance for coating thickness verification.
AMPP / SSPC
Surface preparation and coating application standards from AMPP (formerly NACE and SSPC), covering cleaning, application and inspection practice.
Project specifications
Client and project-specific coating specifications frequently define surface preparation, paint system, application conditions and acceptance criteria that supplement the international standards.
Vendor Inspection Standards
Vendor inspection does not operate under one universal code. The applicable requirements depend on the equipment being manufactured, the purchase specification, Inspection and Test Plan, contractual requirements and relevant product or fabrication standards.
For pressure equipment, piping, structural steel, rotating equipment or packaged systems, the purchase specification and ITP define the hold points, witness points, FAT activities and documentation the vendor inspector verifies against.
Client, EPC and Industry-Specific Requirements
In addition to international codes, projects frequently apply their own technical requirements. These may take precedence over or supplement the base standard.
- Client technical specifications
- EPC contractor procedures
- Classification society requirements (e.g. DNV, ABS, LR, BV)
- Project-specific inspection and test plans
- Purchase order quality requirements
- Sector-specific standards (e.g. offshore, nuclear, rail)
The correct standard, edition and acceptance level should always be confirmed from the project's controlled documentation. Where multiple documents apply, Dilenza works to the hierarchy defined by the client or project.
Qualification and Standards Work Together
A qualified inspector understands both the certification scheme and the applicable standard. The qualification confirms the inspector's competence; the standard defines what they are inspecting against.
For NDT personnel, projects may specify certification schemes such as ISO 9712 or other applicable requirements. The required method, level and certification scheme should come from the controlled project documentation.
The correct qualification, level, standard, edition and inspector responsibilities should always be confirmed before assignment.
Standards and Codes FAQ
- What standards do Dilenza inspectors work to?
- Dilenza inspectors work to the standards and codes defined by the project specification. These can include AWS, ASME, API, ISO, EN, AMPP, SSPC, classification requirements and client-specific procedures.
- What if my project does not specify a standard?
- Send us the available project documentation. We can review the equipment, scope and applicable requirements to help confirm the relevant standards before an inspector is proposed.
- Do coating and welding inspection use the same standards?
- No. Welding inspection is governed by welding codes such as AWS D1.1, ASME IX, API 1104, ISO 5817 and EN 15085. Protective coating inspection is governed by standards such as ISO 12944, ISO 8501, ISO 8502 and AMPP/SSPC specifications.
- Can Dilenza inspect to client-specific specifications?
- Yes. Client, EPC and industry-specific requirements frequently supplement or take precedence over international codes. Dilenza inspectors work to the document hierarchy defined by the project.
- How are NDT certification schemes handled?
- For NDT personnel, projects may specify certification schemes such as ISO 9712 or other applicable requirements. The method, level, certification scheme and inspector responsibilities should come from the controlled project documentation.
- Where is the applicable standard confirmed?
- The standard, edition, addenda and acceptance level should be confirmed from the project specification, ITP, purchase order or other controlled documentation before inspection begins.
- Which standard applies to vendor inspection?
- Vendor inspection does not operate under one universal code. The applicable requirements depend on the equipment, the purchase specification, the Inspection and Test Plan and the relevant product or fabrication standards. Dilenza confirms these from the controlled project documentation before an inspector is proposed.
Need an Inspector for a Specific Standard or Code?
Send us the: Supplier Location · Equipment · Inspection Scope · Required Qualification · Applicable Standards · Dates. If the applicable standard is not yet defined, attach the available project documentation and we can review the requirement with you.
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Tell us what your project requires. We will review the scope and identify the most suitable inspector profile for the assignment.
Whether you require a certified welding inspector for one day, a coating inspector for a defined project stage or a resident inspector for a long-term site position, Dilenza can support your request.