NOM-002-CONAGUA-2021, the new Official Mexican Standard for water closets, urinals, and related accessories, took effect on May 28, 2023. Developed by the Norma Oficial Mexicana (NOM), this standard establishes the minimum specifications that sanitary appliances and their respective accessories must meet. It mandates the effectiveness of the plumbing products’ hydraulic operation, the tightness of their seals and accessories, and their efficient use of water.
NOM-002-CONAGUA-2021 represents Mexico’s response to two pressing realities: the prevalence of low-quality (i.e., high water consumption) plumbing products in the Mexican market and the threat posed by climate change, necessitating water conservation efforts throughout the country.
Current State: Low-Quality Plumbing Products
The plumbing industry in Mexico is currently grappling with lingering supply-chain challenges that are widespread among manufacturers worldwide, stemming from the aftermath of the COVID-19 pandemic. The need to acquire any available component or replacement parts amid global shortages have, to some extent, contributed to the lowered quality of plumbing fixtures and accessories.
However, the predominant factor contributing to the increase of low-quality products in the Mexican market, whether domestically manufactured or imported, is the comparatively less stringent nature of the previous NOM standards covering water closets and accessories.
Under the previous standard, NOM-009-CONAGUA-2001, water closets were certified without any requirement for their plumbing fittings, such as fill valves or flush valves, to be certified under their respective standard, NOM-010-CONAGUA-2000.
Consequently, importers could integrate the fittings into the end product (i.e., the water closet) regardless of whether these component parts adhered to the standard that applied to them. This allowed an untold number of seemingly certified, but poor-quality water closets to enter the Mexican market.
Current State: The Urgent Need for Water Conservation
The recognition of water as a finite resource in need of protection and conservation, first highlighted globally at the inaugural United Nations Water Conference in 1977,1 has taken on a greater sense of urgency as climate change and global warming continue to take their toll on nations around the world. A 2019 UNESCO Report entitled “Water, Megacities and Global Change,” 2 detailed Mexico’s water consumption history — including a 20-fold increase in Mexico City’s population over the past 80 years,3 reaching an estimated 22 million inhabitants in 20194 – and highlighted its looming water consumption crisis.
According to the report, studies suggest that in the years to come, various regions in Mexico will likely experience “an increase in temperature and a decrease in rainfall… and the occurrence of more severe, frequent and prolonged droughts.” 5 For Mexico, water conservation is a national priority.
Since water closets consume more water than any appliance or device within the home — up to 30% of in-home water use, on average6 — manufacturers’ compliance with NOM-002-CONAGUA-2021 holds great potential for water conservation throughout Mexico. This potential is even more significant when considering the water consumption of flushometer-valve water closets — the kind used in commercial, industrial, and institutional settings, such as office buildings, stadiums, and airports.
The older flushometer-valve units consume water at levels that far exceed typical residential water closets.7
NOM-002-CONAGUA-2021: Part of the Solution
In a market flooded with sub-standard plumbing products and the looming threat of water shortages and drought, the importance of NOM-002-CONAGUA-2021 cannot be overstated. As detailed in the following section, the new standard addresses the critical loophole that allowed the sale of water closets with uncertified accessories/components as wholly certified fixtures. Additionally, it establishes a level of water consumption that promises considerable water savings in the years and decades to come.
NOM-002-CONAGUA-2021: What is New
The new NOM introduces the following requirements:
- Certification of individual fittings — All fittings and components, such as fill valves, flush valves, and flappers, must be certified individually.
- Products certified together must be sold together — Water closets with fill valves, flush valves, and flappers must be marketed with the same accessories used during testing, with each accessory holding individual certification.
Manufacturers must choose between two certification options:
- Obtain a single certificate for the water closet as an end product, which includes the water closet, fill valve, flush valve, and flapper.
- Obtain individual certificates for each
- Urinals now require certification — Due to Mexico’s broader water conservation efforts, manufacturers are required to certify all water- consuming devices and appliances, including urinals. This represents a significant change, as urinals did not require certification under the previous NOM. Although urinals consume less water than water closets, accounting for them in the certification process is now essential.
Note: Certification under NOM-002-CONAGUA-2021 is not required for:
- a) Covers, seats, and parts that do not intervene in the hydraulic operation of toilets and urinals.
- b) Latrines or outhouses, toilets for land and marine vehicles, and waterless training toilets.
- c) Bidets.
Minimum Static Pressure for Testing: NOM vs. ASME
Manufacturers should note that testing static pressure for gravity flush-tank water closets under NOM-002- CONAGUA-2021 is only one-third to one-fifth of that required by ASME for the U.S. market. While ASME requires a minimum static pressure of 140 kPa, NOM requires only 25 kPa as “low pressure”.
The following table compares NOM and ASME requirements for the seven tests for gravity flush-tank water closets:
The New NOM: Potential Challenges for Manufacturers
The significantly lower minimum static pressure for testing under NOM-002-CONAGUA-2021 relative to ASME A112.19.2 / CSA B45.1 may have an impact on testing.
For instance, the trap-seal test requires a minimum trap-seal depth of 51 mm. The lower water pressure means there is less water after flushing and during the fill time, potentially causing test failures with regards to the waste extraction or granule ball tests.
The time-of-supply test for fill valves requires that the valve fills the water closet tank in under 3 minutes.
Once again, the low pressure may extend the filling time beyond 3 minutes, resulting in a test failure.
Manufacturers may need to work with a certification body to find solutions and enable compliance with the NOM.
CSA Group: A Trusted Service Provider
At CSA Group, we are one of only two certification bodies outside Mexico authorized to certify products for the Mexican market.
While nearly all approved testing laboratories and certification bodies for plumbing products intended for the Mexican market are located within Mexico. CSA Group is one of only two certification bodies with laboratories outside of Mexico that are authorized to certify water closets and related products for the Mexican market.
Testing and certifying products with CSA Group offers several advantages for manufacturers located outside of Mexico. These advantages can include reduced travel, less complicated logistics, and overall convenience. This proves especially beneficial in instances of testing failures, allowing manufacturers to address issues directly with the CSA Group laboratory closest to them — avoiding the need to travel to Mexico or engage with a third-party organization within Mexico to assist with the remediation.
The CSA Group Difference
With over a century of experience in standards development, testing, and certification, CSA Group and its team of experts can help guide manufacturers through the challenges of standards compliance across multiple regions in a global marketplace. With more than 30 laboratories in 13 countries, CSA Group keeps on top of standards-related developments as they happen around the world.
When you work with CSA Group, you will interact directly with the certifier assigned to your project. This gives you direct access to a wealth of technical expertise in the standards that affect your business.
Our direct-contact approach helps your compliance testing run efficiently. In the unfortunate event of a failure or non-compliance, our team’s collective expertise can help you understand the problem, so that you are well-positioned and have the information you need, to make the necessary corrections and get your project back on track.
References:
- United Nations Water Conference https://en.wikipe- org/wiki/United_Nations_Water_Conference
- Water, Megacities and Global Change, UNESCO, https://unesdoc.unesco.org/in/documentViewer.xht- ml?v=2.1.196&id=p::usmarcdef_0000367866&high- light=CONAGUA&file=/in/rest/annotationSVC/ DownloadWatermarkedAttachment/attach_im- port_1bb2a88b-aadb-4956-82e5-9430d8c7b- b09%3F_%3D367866eng.pdf&locale=en&- multi=true&ark=/ark:/48223/pf0000367866/ PDF/367866eng.pdf#Programme%20Unesco%20 indd%3A.28015%3A18, p. 76-77.
- Water, Megacities and Global Change, UNESCO, https://unesdoc.unesco.org/in/documentViewer.xht- ml?v=2.1.196&id=p::usmarcdef_0000367866&high- light=CONAGUA&file=/in/rest/annotationSVC/ DownloadWatermarkedAttachment/attach_im- port_1bb2a88b-aadb-4956-82e5-9430d8c7b- b09%3F_%3D367866eng.pdf&locale=en&- multi=true&ark=/ark:/48223/pf0000367866/ PDF/367866eng.pdf#Programme%20Unesco%20 indd%3A.28015%3A18, p. 76-77.
- Water, Megacities and Global Change, UNESCO, https://unesdoc.unesco.org/in/documentViewer.xht- ml?v=2.1.196&id=p::usmarcdef_0000367866&high- light=CONAGUA&file=/in/rest/annotationSVC/ DownloadWatermarkedAttachment/attach_im- port_1bb2a88b-aadb-4956-82e5-9430d8c7b- b09%3F_%3D367866eng.pdf&locale=en&- multi=true&ark=/ark:/48223/pf0000367866/ PDF/367866eng.pdf#Programme%20Unesco%20 indd%3A.28015%3A18, p. 15.
- Water, Megacities and Global Change, UNESCO, https://unesdoc.unesco.org/in/documentViewer.xht- ml?v=2.1.196&id=p::usmarcdef_0000367866&high- light=CONAGUA&file=/in/rest/annotationSVC/ DownloadWatermarkedAttachment/attach_im- port_1bb2a88b-aadb-4956-82e5-9430d8c7b- b09%3F_%3D367866eng.pdf&locale=en&- multi=true&ark=/ark:/48223/pf0000367866/ PDF/367866eng.pdf#Programme%20Unesco%20 indd%3A.28015%3A18, p. 76-77.
- S. Environmental Protection Agency – Residential Toilets, https://www.epa.gov/watersense/residen- tial-toilets
- S. Environmental Protection Agency – Commercial Toilets, https://www.epa.gov/watersense/commer- cial-toilets
- The International Association of Plumbing and Mechanical Officials (IAPMO) https://www. org/media/20466/summary-of-chang- es-asme-a112192pluscsa-b451-2013plusup- date-2018.pdf
- ASSE – American Society of Sanitary Engineering https://www.asse-plumbing.org/media/22305/ pdf