Product Background Materials

This page provides background information about the specification development process associated with WaterSense labeled products. The current versions of the specification for each product can be found on the Specification tab for the respective product in the Products section.

On This Page:

• Residential Toilet Background
• Private Lavatory (Bathroom Sink Faucet) Background
• Flushing Urinals Background
• Flushometer Valve Toilets Background
• Showerheads Background
• Weather Based Irrigation Controllers Background
• Pre-Rinse Spray Valves Background
• Spray Sprinkler Bodies Background
• Soil Moisture-Based Irrigation Controllers Background
• Point-of-Use Reverse Osmosis Systems
• Pool Covers Background (no specification)

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Residential Toilet Background

Background Materials

EPA's Response to Public Comments on the Draft of Version 2.0 of the Specification for Tank-Type Toilets

• Draft Version 2.0 of the Specification for Tank-Type Toilets Public Comment Compilation (pdf) (2.97 MB, March 2024)
• Draft Version 2.0 of the WaterSense Specification for Tank-Type Toilets Public Comment Response (pdf) (295.31 KB, May 2024)

Draft Version 2.0 of the WaterSense Specification for Tank-Type Toilets and Supporting Documents

EPA issued a draft Version 2.0 of the WaterSense Specification for Tank-Type Toilets in December 2023.

• WaterSense Specification for Tank-Type Toilets, Version 2.0 (DRAFT) Cover Letter (pdf) (152.94 KB)
• Draft Version 2.0 of the WaterSense Specification for Tank-Type Toilets (pdf) (224.81 KB)
• Draft Version 2.0 of the WaterSense Specification for Tank-Type Toilets – Redline Comparison to Version 1.2 (pdf) (600.4 KB)
• Draft Summary of Revisions to the WaterSense Specification for Tank-Type Toilets (pdf) (232.8 KB)

On January 9, 2024, EPA held a virtual public meeting to discuss the suggested criteria within the specification and obtain feedback.

• Draft Version 2.0 of the Specification for Tank-Type Toilets Public Meeting Presentation (pdf) (2.29 MB)
• Draft Version 2.0 of the Specification for Tank-Type Toilets Public Meeting Recording

Notice of Intent to Revise the Specification and Supporting Documents

EPA issued a Notice of Intent (NOI) to revise the WaterSense Specification for Tank-Type Toilets in June 2023.

• WaterSense Notice of Intent to Revise the Specification for Tank-Type Toilets (pdf) (381.52 KB, June 2023)

On July 19, 2023, EPA held a public meeting to discuss the NOI and obtain stakeholder feedback. Interested parties had the opportunity to submit comments on the NOI until August 2023.

• Tank-Type Toilets NOI Public Meeting Presentation (pdf) (2.44 MB)
• Tank-Type Toilets NOI Public Meeting Recording
• Tank-Type Toilets NOI Public Meeting Summary (pdf) (253.41 KB)
• Tank-Type Toilets NOI Public Comment Compilation (pdf) (1.91 MB)

Version 1.1 of the WaterSense Specification for Tank-Type Toilets and Supporting Materials

• Version 1.1 of the WaterSense Specification for Tank–Type Toilets (PDF)(14 pp, 108 K, About PDF)
• Summary of Revisions to the WaterSense Specification for Tank–Type Toilets (PDF) (5 pp, 52 K, About PDF)

Version 1.0 of the WaterSense Tank-Type High–Efficiency Toilet Specification and Supporting Materials

• Version 1.0 of the WaterSense Tank–Type High-Efficiency Specification (PDF) (12 pp, 166 K, About PDF)
• WaterSense Labeled Toilet Specification Supporting Statement (PDF) (4 pp, 69 K, About PDF)

EPA's Response to the Public Comments on the Draft High-Efficiency Toilet Specification

EPA provided a response to public comments received on the draft specification:

• Response to Issues Raised During Public Comment on April 2006 Draft Specifications for WaterSense Labeling of Tank-Type High-Efficiency Toilets (PDF) (16 pp, 200 K, About PDF) 

Stakeholder Comments on the Draft High-Efficiency Toilet Specification

Interested parties had the opportunity to submit comments until late June 2006:

• Comments: High-Efficiency Toilets (PDF) (51 pp, 585 K, About PDF)

Draft High-Efficiency Toilet Specification

EPA issued draft specifications in early April 2006:

• High-Efficiency Toilet Announcement Cover Letter (PDF) (2 pp, 354 K, About PDF)
• Draft High-Efficiency Toilet Specification (PDF) (14 pp, 78 K, About PDF)

Private Lavatory (Bathroom Sink Faucet) Background

Background Materials

EPA's Response to the Public Comments

EPA provided a response to public comments received on the draft specifications:

• Response to Public Comments Received on February 2007 Draft WaterSense High-Efficiency Bathroom Sink Faucet Specification (PDF) (12 pp, 105 K, About PDF)

Stakeholder Comments on High-Efficiency Bathroom Sink Faucet Specification

Interested parties had the opportunity to submit comments until late May 2007:

• Comments: High-Efficiency Bathroom Sink Faucets (PDF) (36 pp, 213 K, About PDF)

Draft High-Efficiency Bathroom Sink Faucet Specification

EPA issued a draft specification in February 2007:

• High-Efficiency Bathroom Sink Faucet Cover Letter (PDF) (2 pp, 117 K, About PDF)
• Draft High-Efficiency Bathroom Sink Faucet Specification (PDF) (3 pp, 112 K, About PDF)
• Draft High-Efficiency Bathroom Sink Faucet Specification Supporting Statement (PDF) (7 pp, 179 K, About PDF)

On March 1, 2007, EPA hosted a call with stakeholders to discuss the Draft Specification for High-Efficiency Bathroom Sink Faucets. For more information, please see the presentation from the public meeting (PDF) (25 pp, 178 K, About PDF).

Flushing Urinals Background

Background Materials

EPA's Response to the Public Comments

EPA provided a response to public comments received on the draft specification:

• Response to Public Comments Received on January 2009 Draft WaterSense         High-Efficiency Flushing Urinal Specification  (PDF) (23 pp, 120 K, About PDF)

Stakeholder Comments on Draft High-Efficiency Flushing Urinal Specification

Interested parties had the opportunity to submit comments until late March 2009:

• Comments: Draft High-Efficiency Flushing Urinal (PDF) (77 pp, 1.7 MB, About PDF)

Public Meeting on the Draft High-Efficiency Flushing Urinal Specification

On February 5, 2009, EPA hosted a public meeting on the draft high-efficiency flushing urinal specification. For more information, please review:

• Meeting Summary (PDF) (5 pp, 37 K, About PDF)
• Draft High-Efficiency Flushing Urinal Specification Presentation (PDF) (16 pp, 147 K, About PDF)

Draft High-Efficiency Flushing Urinal Specification

EPA issued a draft High-Efficiency Flushing Urinal Specification in January 2009.

• Draft High-Efficiency Flushing Urinal Specification Cover Letter (PDF) (2 pp, 24 K, About PDF)
• Draft High-Efficiency Flushing Urinal Specification (PDF) (3 pp, 42 K, About PDF)
• Draft High-Efficiency Flushing Urinal Specification Supporting Statement (PDF) (7 pp, 44 K, About PDF)

Notification of Intent

EPA issued a notification of intent to develop a specification for high-efficiency urinals in May 2008:

• Notification of intent (NOI) (PDF) (6 pp, 56 K, About PDF)

Flushometer Valve Toilets Background

Background Materials

EPA’s Response to Public Comments

Interested parties had the opportunity to submit comments on the draft specification through March 2015. In addition, on January 15, 2015, EPA hosted a stakeholder teleconference and webinar to discuss the development and content of the draft specification. For more information, please review the following documents:

• Response to Public Comments Received on December 2014 WaterSense Draft Specification for Flushometer-Valve Water Closets (PDF) (27 pp, 336 K, About PDF)
• Comments on the Draft Specification for Flushometer-Valve Water Closets (79 pp, 13.8 MB, About PDF)
• Flushometer-Valve Toilets Draft Specification Public Meeting Summary (11 pp, 267 K, About PDF)
• Flushometer-Valve Toilets Draft Specification Public Meeting Presentation (32 pp, 697 K, About PDF)

Draft Specification for Flushometer-Valve Water Closets and Supporting Documentation

On December 18, 2014, EPA released its Draft Specification for Flushometer-Valve Water Closets. The draft specification and supporting documentation are found below.

• Draft Specification for Flushometer-Valve Water Closets Cover Letter (2 pp, 142 K, About PDF)
• Draft Specification for Flushometer-Valve Water Closets (7 pp, 226 K, About PDF)
• Draft Specification for Flushometer-Valve Water Closets Supporting Statement (10 pp, 267 K, About PDF)

Notice of Intent

In August 2013, EPA issued a Notice of Intent (NOI) to develop a draft specification for flushometer-valve toilets. On September 12, 2013, EPA held a public meeting to address questions regarding the NOI and gather input from stakeholders for specification development. For more information, please review the following documents:

• Flushometer-Valve Toilets NOI (12 pp, 100 K, About PDF)
• Flushometer-Valve Toilets NOI Public Meeting Summary (12 pp, 145 K, About PDF)
• Flushometer-Valve Toilets NOI Public Meeting Presentation (43 pp, 266 K, About PDF)

Showerheads Background

Background Materials

Version 1.0 of the WaterSense Specification for Showerheads and Support Materials

• WaterSense Specification for Showerheads (PDF) (11 pp, 265K, About PDF)
• WaterSense Specification for Showerheads Supporting Statement (PDF) (12 pp, 132K, About PDF)
• Detailed Drawings for the Force Balance Test Apparatus (PDF) (18 pp, 400K, About PDF)

EPA's Response to the Public Comments

EPA provided a response to public comments received on the draft specification:

• Response to Public Comments Received on the September 2009 WaterSense Draft Specification for Showerheads (PDF) (17 pp, 140 K, About PDF)

Stakeholder Comments on Draft Specification for Showerheads

Interested parties had the opportunity to submit comments until early November 2009:

• Comments: Draft Specification for Showerheads (PDF) (20 pp, 184 K, About PDF)

Public Meeting on the Draft Specification for Showerheads

On October 21, 2009, EPA held a teleconference and Webinar with stakeholders to discuss the Draft Specification for Showerheads. For more information, please review:

• Meeting Summary (PDF) (4 pp, 32 K, About PDF)
• Draft Specification for Showerheads Presentation (PDF) (39 pp, 304 K, About PDF)

Draft Specification for Showerheads

EPA issued a Draft Specification for Showerheads in September 2009.

• Draft Specification for Showerheads Cover Letter (PDF) (2 pp, 391 K, About PDF)
• Draft Specification for Showerheads (PDF) (11 pp, 164 K, About PDF)
• Draft Specification for Showerheads Supporting Statement (PDF) (11 pp, 96 K, About PDF)
• Detailed Drawings for the Force Balance Test Apparatus (PDF) (18 pp, 400 K, About PDF)

Notification of Intent

In August 2007, EPA initiated specification development for showerheads. Please review the notification of intent to develop a specification for showerheads for further background information.

• Notification of Intent (NOI) (PDF) (5 pp, 48 K, About PDF)

Weather Based Irrigation Controllers Background

Background Materials

Version 1.0 of the WaterSense Specification for Weather-Based Irrigation Controllers and Supporting Statement

• WaterSense Specification for Weather-Based Irrigation Controllers (Redline Strikeout Version 1.0 and 1.1) (PDF) (11 pp, 183 KB, About PDF)
• WaterSense Specification for Weather-Based Irrigation Controllers, Version 1.0 (PDF) (24 pp, 189k)
• WaterSense Specification for Weather-Based Irrigation Controllers Supporting Statement (PDF) (13 pp, 123K)

EPA's Response to Public Comments

EPA provided a response to public comments received on the draft specification:

• Response to public comments received on the Revised Draft Specification for Weather-Based Irrigation Controllers (PDF) (39 pp, 280 K, About PDF)

Revised Draft Specification for Weather-Based Irrigation Controllers

In January 2011, EPA released a revised draft specification for weather-based irrigation controllers for public comment. This revised draft includes several significant changes to the first draft, which are outlined in the supplemental documents below.

Revised Draft Specification for Weather-Based Irrigation Controllers Supporting Documentation

• Revised Draft Specification for Weather-Based Irrigation Controllers Cover Letter (PDF) (2 pp, 480 K, About PDF)
• Revised Draft Specification for Weather-Based Irrigation Controllers (PDF) (8 pp, 64 K, About PDF)
• Summary of Major Changes to the Revised Draft Specification for Weather-Based Irrigation Controllers (PDF) (6 pp, 50 K, About PDF)

To assist manufacturers in certifying and labeling their products once the final specification is released, EPA developed guidance on the certification process.

• Draft Supplemental Guidance for WaterSense Certification and Labeling of Weather-Based Irrigation Controllers (PDF) (10 pp, 73 K, About PDF)

WaterSense also conducted follow-up research at the University of Florida regarding the use of the Smart Water Application Technologies™ (SWAT) protocol as the performance test for the specification.

• Examination of SWAT Protocol Utilizing a Performance Analysis of Weather-Based Irrigation Controllers: Update with Extended Data (2011) (PDF) (48 pp, 616 K, About PDF)
• Examination of SWAT Protocol Utilizing a Performance Analysis of Weather-Based Irrigation Controllers (2009) (PDF) (111 pp, 4.5 MB, About PDF)

Stakeholder Comments on the Revised Draft Specification for Weather-Based Irrigation Controllers

Interested parties had the opportunity to submit comments until March 21, 2011.

• Comments: Revised Draft Specification for Weather-Based Irrigation Controllers (PDF) (87 pp, 711KB, About PDF)

Public Meeting on the Revised Draft Specification for Weather-Based Irrigation Controllers

On February 23, 2011, WaterSense held two public meeting webinars. For more information, please review:

• Meeting Summary (PDF) (13 pp, 76 K, About PDF)
• Revised Draft Specification for Weather-Based Irrigation Controllers Presentation (PDF) (28 pp, 831 K, About PDF)

First Draft Specification—November 2009

EPA issued an initial draft specification for weather-based irrigation controllers in November 2009. For more information, please review:

Draft Specification for Weather-Based Irrigation Controllers Supporting Documentation

• Draft Specification for Weather-Based Irrigation Controllers Cover Letter (PDF) (2 pp, 441 K, About PDF)
• Draft Specification for Weather-Based Irrigation Controllers (PDF) (5 pp, 52 K, About PDF)
• Draft Specification for Weather-Based Irrigation Controllers Supporting Statement (PDF) (12 pp, 87 K, About PDF)
• Examination of SWAT Protocol Utilizing a Performance Analysis of Weather-based Irrigation Controllers (PDF) (111 pp, 4.5 MB, About PDF)

Stakeholder comments on Draft Specification for Weather-Based Irrigation Controllers

Interested parties had the opportunity to submit comments until January 18, 2010

• Comments: Draft Specification for Weather-Based Irrigation Controllers (PDF) (105 pp, 4.3MB)

Public Meeting on the Draft Specification for Weather-Based Irrigation Controllers

On December 4, 2009, EPA held a public meeting in San Antonio, Texas, to discuss the Draft Specification for Weather-Based Irrigation Controllers. In addition, WaterSense held two webinars on December 16, 2009. For more information, please review:

• Meeting Summary (PDF) (13 pp, 76 K, About PDF)
• Draft Specification for Weather-Based Irrigation Controllers Presentation (PDF) (28 pp, 831 K, About PDF)

Notification of Intent

On April 19, 2007, EPA hosted a meeting with stakeholders to discuss the technical issues and specification development process for weather-based irrigation control technologies. For more information, please review:

• Meeting Summary (PDF) (24 pp, 96 K, About PDF)
• Meeting Agenda (PDF) (2 pp, 26 K, About PDF)
• EPA's Notification of Intent (PDF) (14 pp, 193 K, About PDF)
• Weather- or Sensor-Based Irrigation Control Technologies Notification of Intent Stakeholder Meeting Presentation (PDF) (18 pp, 2.4 MB, About PDF)
• Overview of Notification of Intent and Technical Issues Presentation (PDF) (44 pp, 4.6 MB, About PDF)

• Climate-Based Irrigation Controller Protocol Presentation (PDF) (18 pp, 983 K, About PDF)

Certification and Labeling

On September 15, 2008, EPA hosted a webinar to familiarize irrigation manufacturers of weather-based irrigation controllers with the WaterSense certification and labeling process. For more information, please review:

• Meeting Summary (PDF) (6 pp, 39 K, About PDF)
• WaterSense Certification and Labeling Presentation (PDF) (26 pp, 193 K, About PDF)

Pre-Rinse Spray Valves Background

Background Materials

Final Specification

EPA released a final WaterSense Specification for Commercial Pre-Rinse Spray Valves on September 19, 2013. The specification was sunset on January 1, 2019.

• WaterSense Specification for Commercial Pre-Rinse Spray Valves (PDF) (5 pp, 163 K, About PDF)
• WaterSense Specification for Commercial Pre-Rinse Spray Valves Supporting Statement (PDF) (10 pp, 281 K, About PDF)

EPA’s Response to Public Comments

Interested parties had the opportunity to submit comments on the WaterSense Draft Specification for Commercial Pre-Rinse Spray Valves until early April 2013. In addition, on March 20, 2013, EPA held a teleconference and webinar with stakeholders to discuss the draft specification. For more information, please review:

• Response to Public Comments Received on the February 2013 WaterSense Draft Specification for Commercial Pre-Rinse Spray Valves (PDF)  (14 pp, 226 K, About PDF)
• Comments: Draft Specification for Commercial Pre-Rinse Spray Valves (PDF)  (33 pp, 329 K, About PDF)
• Meeting Summary (PDF)  (7 pp, 60 K, About PDF)
• Draft Specification for Commercial Pre-Rinse Spray Valves Presentation (PDF) (39 pp, 1.1 MB, About PDF)

Draft Specification for Commercial Pre-Rinse Spray Valves and Supporting Documentation

EPA issued a WaterSense Draft Specification for Commercial Pre-Rinse Spray Valves on February 7, 2013. The draft specification and supporting documentation are found below:

• Draft Specification for Commercial Pre-Rinse Spray Valves Cover Letter (PDF) (2 pp, 36 K, About PDF)
• Draft Specification for Commercial Pre-Rinse Spray Valves (PDF)  (22 pp, 999 K, About PDF)
• Draft Specification for Commercial Pre-Rinse Spray Valves Supporting Statement (PDF)  (12 pp, 130 K, About PDF)

Pre-Rinse Spray Valves Field Study

To ensure the efficiency and performance of high efficiency pre-rinse spray valves before developing a specification, EPA conducted a field study to assess pre-rinse spray valve water use, energy use, and performance. Information regarding the scope and results of the pre-rinse spray valve field study are found below:

• Pre-Rinse Spray Valve Field Study Report (PDF) (136 pp, 1.5 MB, About PDF)
• Pre-Rinse Spray Valve Research Study Scope (PDF) (6 pp, 72 K, About PDF)
• Pre-Rinse Spray Valve Research Needs Meeting Agenda (PDF) (2 pp, 24 K, About PDF)
• Research Needs Meeting Presentation (PDF) (41 pp, 323 K, About PDF)
• Research Needs Meeting Attendee List (PDF) (1 pp, 10 K, About PDF)

Notice of Intent

In July 2009, EPA initiated specification development for commercial pre-rinse spray valves. For further background information, please review the notice of intent to develop a specification for pre-rinse spray valves:

• Pre-Rinse Spray Valves Notice of Intent (PDF) (6 pp, 134 K, About PDF)

Spray Sprinkler Bodies Background

Background Materials

EPA’s Response to Public Comments

Interested parties had the opportunity to submit comments on the draft specification through February 2017. On January 18, 2017, EPA hosted a stakeholder teleconference and webinar to discuss the development and content of the draft specification. For more information, please review the following documents:

• Response to Public Comments Received on the WaterSense Draft Specification for Spray Sprinkler Bodies (PDF) (16 pp, 401 K, About PDF)
• Comments on the Draft Specification for Spray Sprinkler Bodies (PDF) (32 pp, 366 KB, About PDF)
• Spray Sprinkler Bodies Draft Specification Public Meeting Summary (PDF) (6 pp, 63 KB, About PDF)
• Spray Sprinkler Bodies Draft Specification Public Meeting Presentation (PDF) (42 pp, 2.4 MB, About PDF)

Draft Specification for Spray Sprinkler Bodies and Supporting Documentation

On November 17, 2016, EPA released its WaterSense Draft Specification for Spray Sprinkler Bodies. For more information, please review the documents below.

• Draft Specification for Spray Sprinkler Bodies Cover Letter (PDF) (2 pp, 232 K, About PDF)
• Draft Specification for Spray Sprinkler Bodies (PDF) (9 pp, 331 K, About PDF)
• Draft Specification for Spray Sprinkler Bodies Supporting Statement (PDF) (14 pp, 641 K, About PDF)

On December 7, 2016, EPA held an informal information session at the Irrigation Show and Education Conference in Las Vegas, Nevada. At the conference, EPA also presented a technical paper on the development of a test method for spray sprinkler bodies and shared the results of performance testing. 

• Spray Sprinkler Bodies Draft Specification Public Meeting Presentation (PDF)(24 pp, 2.1 MB, About PDF).

A report detailing the methodology and results of our product performance testing is also available:

• Pressure Regulating Spray Sprinkler Body Final Test Report (PDF) (31 pp, 565 K, About PDF)

Notice of Intent for Landscape Irrigation Sprinklers

In July 2014, EPA issued a Notice of Intent (NOI) to develop a specification for landscape irrigation sprinklers. The NOI outlined the performance criteria WaterSense proposed for both high-efficiency nozzles and pressure-regulating sprinkler bodies, and identified issues that still need to be resolved.  WaterSense solicited public comment on the NOI, analyzed the public comments, conducted additional research, determined a path forward for this product category, and briefed stakeholders on the developments.

• Landscape Irrigation Sprinkler NOI (PDF)(11 pp, 321 K, About PDF)
• Landscape Irrigation Sprinkler NOI Comments (PDF)(57 pp, 1.5 MB, About PDF)
• Landscape Irrigation Sprinklers: WaterSense Specification Update (PDF) (9 pp, 0.5 MB, About PDF)

In November 2015, WaterSense decided to move forward with developing a draft specification for spray sprinkler bodies with integrated pressure regulation, but put on hold developing a specification for high-efficiency nozzles. If you have questions on these decisions or on information included in the documents listed above, please contact us at watersense-products@erg.com.

Soil Moisture-Based Irrigation Controllers Background

Background Materials
EPA’s Response to Public Comments

EPA invited all interested parties to comment on the draft specification, through February 1, 2020. On November 20, 2019, EPA held a teleconference and webinar with stakeholders to discuss the draft specification. EPA also presented the same information during a session at the Irrigation Show in Las Vegas, Nevada, on December 5, 2019.

• Comments on the WaterSense Draft Specification for Soil Moisture-Based Irrigation Control Technologies (PDF) (34 pp, 919 K, About PDF)
• Response to Public Comments Received on the WaterSense Draft Specification for Soil Moisture-Based Irrigation Control Technologies (PDF) (30 pp, 362 K, About PDF)
• Draft Soil Moisture-Based Control Technology Specification Public Meeting Presentation (PDF) (59 pp, 4 MB, About PDF)
• View Webinar Recording (Registration Required)
• WaterSense Draft Specification for Soil Moisture-Based Irrigation Control Technologies Public Meeting Summary (PDF)(15 pp, 348 K, About PDF)

Draft Specification

EPA released a draft specification for WaterSense labeled soil moisture-based irrigation control technologies on November 7, 2019.

• WaterSense Draft Specification for Soil Moisture-Based Irrigation Control Technologies (PDF) (8 pp, 294 K, About PDF)
• WaterSense Draft Specification for Soil Moisture-Based Irrigation Control Technologies Supporting Statement (PDF) (18 pp, 615 K, About PDF)
• WaterSense Draft Specification for Soil Moisture-Based Irrigation Control Technologies Cover Letter (PDF) (2 pp, 117 K, About PDF)

The University of Florida’s Soil Moisture-Based Irrigation Controller Final Test Report (PDF) (17 pp, 3 MB, About PDF) details their performance testing of SMSs. The WaterSense Draft Specification for Soil Moisture-Based Irrigation Control Technologies references this report as it provides supporting data for criteria included in the draft specification.

Specification Update for Soil Moisture-Based Irrigation Controllers

In December 2017, WaterSense provided a specification update to document progress made to date and describe remaining research needs.

• Soil Moisture-Based Irrigation Control Technologies: WaterSense Specification Update (PDF) (9 pp, 515 K, About PDF)

Notice of Intent for Soil Moisture-Based Irrigation Controllers

In May 2013, WaterSense issued a notice of intent (NOI) to develop a specification for bypass-type soil moisture-based control technologies.

• WaterSense Notice of Intent (NOI) to Develop a Draft Specification for Soil Moisture-Based Control Technologies (pdf) (233.7 KB)

Point-of-Use Reverse Osmosis Systems Background

Background Materials

EPA’s Response to Public Comments

EPA provided a response to the public comments received on the draft specification and specification update.

• ​​​​​​​RO Systems Specification Development Public Comment Response (pdf) (364.48 KB)
• RO Systems Specification Development Update Public Comments (pdf) (1.06 MB)
• RO Systems Draft Specification Public Comments (pdf) (2.01 MB)

Specification Development Update

On February 22, 2024, EPA released an update regarding specification development to inform interested parties of the development status and solicit final comments on updated requirements to the product packaging and documentation criteria. For more information, please review:

• WaterSense Specification Development Update: Point-of-Use Reverse Osmosis Systems (pdf) (192.94 KB)

Public Meeting on the Draft Point-of-Use RO Systems

On January 12, 2023, EPA hosted a public meeting on the draft point-of-use RO systems specification. For more information, please review:

• RO Systems Draft Specification Public Meeting Presentation (pdf) (2.8 MB)
• RO Systems Draft Specification Public Meeting Summary (pdf) (424.27 KB)
• View webinar recording

Draft Specification for Point-of-Use RO Systems

On December 1, 2022, EPA released a draft specification for WaterSense labeled point-of-use RO systems. The draft specification and supporting documentation are found below:

• WaterSense Draft Specification for Point-of-Use Reverse Osmosis Systems Cover Letter (pdf) (170.98 KB)
• WaterSense Draft Specification for Point-of-Use Reverse Osmosis Systems (pdf) (261.17 KB)
• WaterSense Draft Specification for Point-of-Use Reverse Osmosis Systems Supporting Statement (pdf) (577.79 KB)

Notice of Intent

In January 2022, EPA initiated specification development for showerheads. On February 16, 2022, EPA held a public meeting to review the Notice of Intent and answer questions. Register to view a recording of the webinar. For more information, please review:

• Point-of-Use Reverse Osmosis Systems NOI (pdf) (670.04 KB)
• RO Systems NOI Public Meeting Presentation (pdf) (2.66 MB)
• RO Systems NOI Public Meeting Summary (pdf) (269.77 KB)
• RO Systems NOI Public Comments (pdf) (2.74 MB)  - (comments received through May 24, 2022)

Pool Covers Background

In September 2018, WaterSense issued a notice of intent (NOI) to develop a specification for pool covers to help reduce water waste in swimming pools. After research and consideration, WaterSense made the decision to not develop a specification for pool covers. Instead, WaterSense developed a guide to promote water efficiency in the design and management of pools. 

• Pool Covers NOI (PDF) (22 pp, 777 K, About PDF)
• Pool Covers NOI Public Meeting Presentation (PDF) (60 pp, 3 MB, About PDF)
• Pool Covers NOI Public Meeting Summary (PDF) (11 pp, 448 K, About PDF)
• Pool Covers NOI Public Comments (as of May 2019) (PDF)(35 pp, 4 MB, About PDF)