What is NOM? NOM stands for Norma Oficial Mexicana. Although it is often translated as “Mexican Official Standard,” a NOM is more accurately understood as a mandatory Mexican technical regulation issued by a competent regulatory authority.

NOMs can establish mandatory requirements for products, processes, services, installations, labelling, safety, energy efficiency, environmental protection, telecommunications, health, occupational safety and many other regulated areas.

A NOM becomes relevant when a product, service or activity falls within its defined scope. There is no single universal “NOM certificate” that covers every product sold in Mexico. The applicable NOM and conformity-assessment procedure must first be identified.

In Simple Terms: What Does NOM Mean?

Imagine that you want to sell an electrical controller in Mexico. Mexico may have an official rule saying: “If your product belongs to this category, it must meet these safety or technical requirements before it can be sold.” That mandatory rule may be a NOM. In simple terms, an ISO or IEC document may provide an international technical standard, while a NOM can say “if this product is within the scope of this Mexican regulation, compliance is required for the Mexican market.”

Are NOM Requirements Mandatory?

Yes, when the product, process or service falls within the scope of the applicable NOM. Mexico's official quality-infrastructure platform defines Normas Oficiales Mexicanas as mandatory technical regulations.

This does not mean that every product must comply with every NOM. Each regulation has its own objective, scope, exclusions and technical requirements.

A PLC or HMI, a variable frequency drive, an industrial power supply and a household appliance may therefore be subject to completely different Mexican requirements even though all are electrical products.

What Is the Current Legal Framework Behind NOMs?

Mexico's modern quality-infrastructure system is based on the Ley de Infraestructura de la Calidad – Quality Infrastructure Law, published in 2020. This law replaced the previous Federal Law on Metrology and Standardization.

A new Regulation of the Quality Infrastructure Law was published in Mexico's Diario Oficial de la Federación on 4 September 2026, providing the current regulatory framework for implementing the law.

For new products or export projects, old references to the former metrology and standardization legislation should therefore not automatically be treated as the current legal framework.

Are NOM, ISO and IEC the Same Type of Standard?

No. ISO standards and IEC standards are international technical standards. A NOM is a mandatory technical regulation within the Mexican regulatory system when its scope applies.

A Mexican NOM may use an ISO, IEC or other international standard as a technical basis. However, this does not mean that a product complying with IEC or ISO automatically satisfies the Mexican regulatory process.

Mexico may still have its own requirements for scope, conformity assessment, testing, certification, marking, labelling and market access.

What Is the Difference Between NOM and NMX?

Older Mexican technical documentation frequently refers to NMX – Norma Mexicana as well as NOM. The two terms do not have the same regulatory meaning.

NOM is mandatory when its scope applies. Traditional NMX documents generally functioned as voluntary Mexican technical standards unless made mandatory through another legal or contractual mechanism.

Under the 2020 Quality Infrastructure Law, the newer Mexican framework introduced the broader concept of Estándares to replace the previous NMX structure over time. Existing NMX documents can still appear in technical documentation and official catalogues, so their individual status must be checked.

When a document says “Mexican Standard,” check whether it is a NOM, an NMX or an Estándar before deciding whether it is mandatory.

How Is a NOM Number Read?

A NOM should be identified by its complete designation. Looking only at the first number can be misleading.

For example:

NOM-003-SCFI-2014

can be read generally as:

NOM = Norma Oficial Mexicana
003 = regulation identifier within the relevant series
SCFI = identifier associated with the regulatory sector or authority used in the designation
2014 = year identifier associated with that edition

This is why the old idea that “NOM-001 means electrical products, NOM-002 means fire protection, NOM-003 means appliances, NOM-004 means workplace safety” is incorrect.

Different authorities and regulatory sectors can use overlapping numerical identifiers. The complete NOM code, including the authority/sector identifier and year, must be checked.

What Is NOM-001-SEDE-2012?

NOM-001-SEDE-2012 concerns Electrical Installations (Utilization) and is currently listed as valid in Mexico's official PLATIICA standards system.

Its principal subject is electrical installations rather than product certification for an individual PLC, drive or sensor.

This distinction is important in industrial automation. A product may have its own safety or conformity requirements, while the factory electrical installation in which that product is installed can be subject to a different technical regulation.

Product compliance and installation compliance are related, but they are not the same thing.

What Is NOM-003-SCFI-2014?

NOM-003-SCFI-2014 is titled Electrical Products – Safety Specifications. It establishes safety requirements for electrical products within its defined scope.

Mexico's official PLATIICA system currently lists NOM-003-SCFI-2014 as valid, and its 2025 systematic review confirmed continuation of the regulation.

However, it would be incorrect to say that every electrical product automatically falls under NOM-003-SCFI-2014. The scope and exclusions of the regulation must be checked for the exact product.

How Is NOM Compliance Demonstrated?

The conformity-assessment route is not identical for every NOM. Once the applicable NOM has been identified, the next step is to review its conformity-assessment procedure.

Depending on the regulation and product, the process may involve one or more of the following:

• Laboratory testing
• Technical documentation or compliance evidence
• Product certification
• Inspection or verification
• Surveillance or follow-up assessment
• Marking and labelling requirements

Where third-party conformity assessment is required, the laboratory, certification body or inspection body must have the appropriate competence, accreditation and approval for the relevant activity.

Does Every NOM Require a Product Certificate?

No. A NOM being mandatory does not mean that every NOM requires the same type of independent product certificate.

Some regulations use product certification. Others can require testing, verification, inspection, measurement, installation assessment or different forms of conformity evidence.

The phrase “get a NOM certificate for Mexico” is therefore too broad. The correct question is: Which NOM applies, and what conformity-assessment procedure does that NOM require?

What Is the Official NOM Mark?

Mexico uses an official conformity symbol known as the Contraseña Oficial NOM. Its design characteristics and conditions of use are regulated by NOM-106-SCFI-2017.

NOM-106-SCFI-2017 is currently listed as valid in Mexico's official standards platform.

However, it should not be assumed that every product subject to every NOM automatically carries the same mark in the same way. The applicable product regulation and its marking requirements must also be checked.

The logo itself is not proof of compliance unless it is supported by the required conformity-assessment process and documentation.

Do CE or UL Approvals Replace NOM?

Not automatically. CE marking belongs to the European regulatory system, while UL certifications and listings are associated with different North American conformity frameworks.

An IEC, ISO, UL or other international test report may sometimes provide useful technical evidence, depending on the applicable Mexican regulation and conformity-assessment procedure.

However, compliance in another market does not automatically cancel a mandatory Mexican NOM requirement.

Country-specific requirements are covered more broadly in our global standards and conformity systems section.

Why Is NOM Important in Industrial Automation?

An industrial automation system exported to Mexico may include PLCs, HMIs, variable frequency drives, industrial power supplies, control panels, sensors and communications equipment.

These components do not necessarily fall under the same NOM. One device may be affected by product-safety requirements, another by energy or telecommunications rules, while the completed installation may also need to meet Mexican electrical-installation requirements.

For example, a variable frequency drive designed according to the IEC 61800 series provides useful international technical conformity information, but Mexican market-access and installation requirements must still be evaluated separately.

Why Do CE, RCM, NOM and Other Marks Not Replace One Another?

CE, RCM, EAC and Mexico's NOM system belong to different regulatory frameworks in different markets.

The technical requirements may sometimes be based on similar IEC or ISO standards, but the legal obligations, declarations, certification routes, responsible parties and marking rules can still be different.

The same industrial device may therefore carry CE marking for Europe, RCM for Australia/New Zealand and require compliance with one or more applicable NOMs for Mexico.

The hardware can be the same; the legal market-access requirements are not.

How Should an Old NOM Reference Be Interpreted?

Older PLC, drive and power-supply manuals frequently contain NOM references. A year that looks old does not automatically mean that the NOM has been withdrawn.

For example, NOM-001-SEDE-2012 and NOM-003-SCFI-2014 are still shown as valid in Mexico's current official PLATIICA system.

The opposite is also possible: an old manual may reference a NOM that has since been replaced or cancelled.

The current legal status should therefore be checked in PLATIICA or the Diario Oficial de la Federación rather than guessed from the year printed in the standard number.

Why Is NOM Compliance Important for Importers?

Manufacturers and importers supplying regulated products to the Mexican market may need to demonstrate conformity with applicable mandatory technical regulations before or during the import and market-access process.

Depending on the product, this can involve test reports, certificates, conformity documents, labelling requirements or other regulatory evidence.

For this reason, the overseas manufacturer and Mexican importer should identify the complete NOM designation, scope and conformity-assessment procedure before shipment.

Common NOM Mistakes

“NOM-001 is the standard for all electrical products.” Incorrect. NOM-001-SEDE-2012 concerns electrical installations.

“The first NOM number tells you the product category.” Incorrect. The complete designation, including the sector/authority identifier and year, must be checked.

“NOM and ISO are the same type of standard.” Incorrect. A NOM is a mandatory Mexican technical regulation when its scope applies.

“Every NOM requires a certificate.” Incorrect. Conformity-assessment procedures vary between regulations.

“Every NOM product always carries the NOM logo.” Marking requirements must be checked in the applicable product regulation and conformity procedure.

“CE marking means NOM is unnecessary.” Incorrect. European and Mexican regulatory systems are different.

“An old year in the NOM code means the regulation is obsolete.” Incorrect. Current status must be checked in the official Mexican database.

Where Should Mexican NOM Compliance Start?

The correct starting point is not to search randomly for a “NOM certificate.”

Identify the product → identify potentially applicable NOMs → check the exact scope and exclusions → review the conformity-assessment procedure → determine required testing and documentation → verify the appropriate conformity-assessment body → complete certification or marking where required → verify import and labelling obligations.

Finding a NOM number is not the end of the process; it is the beginning of identifying the correct Mexican compliance route.

Important: NOM requirements can vary according to product type, application, industry and regulatory authority. For a new product or export project, always verify the current status, scope and conformity-assessment procedure using Mexico's official PLATIICA system and the Diario Oficial de la Federación.

Related Standards and Compliance Guides

Industrial Standards  •  Global Standards  •  Device Standards  •  IEC Standards  •  ISO Standards  •  EN Standards

Related Automation Guides

Industrial Automation  •  What Is Automation?  •  PLC & HMI  •  IEC 61800 Drive Standards