ASSE International Listing Evaluation Criteria (LEC) provides manufacturers with an avenue to certify unique, novel products that do not fit the scope of an existing standard. If these products gain traction and market acceptance, the LEC can then be developed into an ASSE Standard through the American National Standards Institute (ANSI) accredited standards development process. One LEC that is currently in this process of becoming an ASSE American National Standard is LEC 2004-2019, Listing Evaluation Criteria for Drinking Water Treatment Systems Using Air as a Source. LEC 2004 was developed to address water conservation in areas that experience droughts or have deteriorating access to safe drinking water. The two primary criteria for such devices are that the water shall be produced at a reasonable cost and the water quality produced shall be safe to consume. Manufacturers looking to certify to LEC 2004, and later the product standard, must comply with the above two criteria by meeting the requirements highlighted throughout the standard. The following summarize the tests listed in LEC 2004 to confirm that an air to water device meets those two criteria.
Section 3.1: Drinking Water Production Rate
This section tests the product at a specific temperature and relative humidity to determine if the amount of water produced over 24 hours is within five percent of the manufacturer’s stated value.
Section 3.2: Fill Volume and Automatic Shut Off for Tank-type Systems
This test is used to determine the total volume that the storage tank of the device can hold, while also ensuring that the shut-off valve turns the system off when the tank is full.
Section 3.3: Energy Efficiency – Drinking Water Produced per Energy Consumed
This test confirms (or denies) the manufacturer’s claims regarding the amount of water produced per energy consumed, and that the ratio is at a minimum of 3.0 L/kWh.
Section 3.4: Backflow Protection
This section requires that a device with an air gap device comply with IAPMO PS 65.
Section 3.5: Microbial Growth Protection
This section tests the device to NSF 55: Ultraviolet Microbiological Water Treatment Systems, or the United States Environmental Protection Agency (U.S. EPA) Guide Standard and Protocol for Testing Microbiological Water Purifiers, to ensure that the device prevents microbial growth.
Section 3.6: Chemical Reduction Performance Testing
This section requires that the device comply with Section 7 of either NSF 42: Drinking Water Treatment Units – Aesthetic Effects or NSF 53: Drinking Water Treatment Units – Health Effects to ensure that filtration equipment meets chemical and particulate reduction requirements. Section 3.6 is only necessary for systems with filtration equipment.
Section 3.7: Life Cycling for Systems with Upstream Connections to Potable Water
This section requires tests from ASSE 1087, Performance Requirements for Commercial and Food Service Water Treatment Equipment Utilizing Drinking Water, to evaluate systems that are subject to an upstream connection to the potable water supply when demand exceeds atmospheric generation.
The remaining sections outline the requirements for materials, installation instructions, and markings of LEC 2004 certified devices. First, material formulations must be provided for all components in contact with water, unless the product or components are compliant with NSF 42, NSF 53, NSF 55, NSF 14: Plastics Piping System Components and Related Materials, NSF 58: Reverse Osmosis Drinking Water Treatment Systems, NSF 60: Drinking Water Treatment Chemicals – Health Effects, or NSF 61: Drinking Water System Components – Health Effects. The material formulations are then used to determine what extraction testing, if any, is required. Manufacturers seeking certification to LEC 2004 must also provide instructions that include information such as drinking water production rate, energy efficiency, and instructions on replacing air and water filters. Finally, markings are required to show the manufacturer or trademark’s name, as well as the type and model number of the system.
ASSE LEC 2004 is currently being developed into ASSE 1090, Performance Requirements for Drinking Water Treatment Systems Using Air as a Source. The working group for ASSE 1090 has already met and collaborated multiple times, and the standard will continue to be refined through working group and Product Standards Committee discussions. The goal
is that ASSE 1090 will be published in 2020.
