American National Standards exist for a wide range of products, providing for a method of test and associated criteria of demonstrated product compliance. Such standards have been applied to the onsite wastewater treatment industry for several decades, as provided for through NSF and our expert committees.
NSF is accredited by the American National Standards Institute (ANSI) to develop and publish American National Standards. The process for developing an American National Standard must properly address consensus, due process, and openness. In the case of the NSF wastewater treatment standards, these are accomplished primarily through a committee structure, with the NSF Joint Committee on Wastewater Technology at the core.
The NSF Joint Committee is comprised of equal representation from the industry, public health, and user communities. Each has approximately 12 seats on the committee. The process often involves input from many others, as provided through sub-committees, or task groups. However, the ultimate decision and voting rights reside with the joint committee. As a consensus body, there must be committee-wide agreement in order for the standard to move forward. This ensures that no one segment of the committee is able to overly influence the outcome.
The standards available today against which NSF conducts onsite wastewater treatment system evaluations include:
NSF/ANSI Standard 40: Residential Wastewater Treatment Systems
NSF/ANSI Standard 41: Non-Liquid Saturated Treatment Systems
NSF/ANSI Standard 46: Evaluation of Components and Devices Used in Wastewater Treatment Systems
NSF/ANSI Standard 245: Wastewater Treatment Systems - Nitrogen Reduction
NSF/ANSI Standard 350: Onsite Residential and Commercial Reuse Treatment Systems
Standard 40 is for residential wastewater treatment systems having rated capacities between 400 gallons (1514 Liters) and 1500 gallons (5678 Liters) per day. The standard is not restrictive in the type of treatment technology. Any system can be evaluated.
The standard includes a wide range of product evaluation methods and criteria for residential treatment systems. Most notably is the ability of the treatment system to produce an acceptable quality of effluent. This is demonstrated during a six month (26 week) test where wastewater of required strength is subjected to the system at the rated capacity of the system as evenly dosed at periods prescribed by the standard. Stress sequences are included to simulate wash day, working parent, power outage, and vacation conditions. The effluent criteria required of a Class I system is based on the U.S. EPA secondary effluent treatment requirements for municipal treatment facilities. Testing can be performed at several test facilities.
In addition to the effluent performance, requirements also exist for product literature, including installation, operation and maintenance, and trouble shooting and repair manuals. The system must also meet minimum requirements for structural integrity, leakage, noise, electrical certification, access ports, failure sensing and signaling equipment (visual and audible alarms), flow design, data plate and service labels.
Standard 41 is for treatment systems that do not utilize a liquid saturated media as a primary means of storing or treating human excreta or human excreta mixed with other organic household materials . These would include composting toilets and similar treatment technologies. The standard requires a minimum six months of performance testing, incorporating design loading and stress testing appropriate to the three classes of systems covered: residential, cottage, and day-use park. A minimum of one system is evaluated in a controlled, laboratory setting, and a minimum of three systems are evaluated in a mature, field setting.
Standard 46, relating to components of wastewater treatment systems, applies to a wide range of products. Standard 46 currently includes performance evaluations for grinder pumps, septic tank effluent filters, chlorination devices, and UV disinfection devices.
As product users, regulatory officials, and manufacturers identify the need for additional performance evaluations for other components of wastewater treatment, the NSF Joint Committee on Wastewater Technology will develop the evaluations and add them to Standard 46.
NSF/ANSI Standard 245 has been developed for residential wastewater treatment systems designed to provide for nitrogen reduction. The evaluation involves six months of performance testing, incorporating stress tests to simulate wash day, working parent, power outage, and vacation conditions. The standard is set up to evaluate systems having rated capacities between 400 gallons and 1500 gallons per day. Technologies testing against Standard 245 must either be Standard 40 certified or be evaluated against Standard 40 at the same time an evaluation is being carried out for Standard 245, as both tests can be run concurrently.
Throughout the testing, samples are collected during design loading periods and evaluated against the pass/fail requirements. A treatment system must meet the following effluent concentrations averaged over the course of the testing period in order to meet Standard 245:
The scope of NSF Standard 240 is for the evaluation of those products used as alternatives to traditional stone or gravel trenches. The emphasis is placed on hydraulics with performance measured over time in comparison to a conventional gravel drain field tested in parallel with the gravelless trench. The standard encompassed both a laboratory test, as applied to newer technologies, and a field evaluation, as applied to technologies in use for 10 years or more.
NSF Standard 350 establishes the minimum materials, design and construction, and performance requirements for onsite residential and commercial reuse treatment systems. As the title implies, it is for both residential and commercial systems. It also encompasses both residential wastewater treatment systems, i.e. those that treat all the wastewater flow from a residence similar to the scope of NSF/ANSI Standards 40 and 245, along with those that treat the graywater portion only. Further, within the graywater portion, systems can be evaluated for treating bathing water only, laundry water only, or both. Reuse applications of the treated effluent include indoor restricted urban water use, such as toilet and urinal flushing, and outdoor unrestricted urban water use, such as surface irrigation.
The purpose of NSF Standard 360 is to establish consistent site selection, sampling, laboratory analysis, and data evaluation methods for obtaining field performance results for onsite wastewater treatment systems. It is applicable only to systems already certified to NSF/ANSI 40 (CBOD5 and TSS reduction) and to NSF/ANSI 245 if appropriate (nitrogen reduction). This then also limits the size of systems consistent with Standard 40 and 245 to 400-1500 gallons/day.
NSF protocols are similar in many ways to the NSF/ANSI Standards, but do not undergo review and approval by the NSF Joint Committee. Instead, they undergo review and approval by a smaller technical panel. The panel includes experts in onsite wastewater, and like the NSF Joint Committee, include stakeholder representation from industry, public health and user communities. Protocols are generally developed for smaller industry sectors. For more information on the Protocol Development process, download the brochure.
Protocol P150 evaluates the impact and fate of a tissue product entering a septic system. Tissues meeting the requirements of this protocol will not substantially increase sludge or scum accumulation, or substantially increase the loading of organic material and solids to the soil drain field. Testing is conducted over a six month period at one of the NSF Wastewater Technology Test Facilities.
Protocol P157 evaluates the health and sanitation characteristics of electrical incinerating devices designed to combust toilet waste. There are minimum requirements for materials, design and construction, performance, and cleanability. Actual use testing is conducted, including analysis of the ash end-product for the presence of fecal coliform microorganisms.