Performance Coding 

As far as is possible, this code is a performance code, meaning that it does not judge systems on what they look like, but rather on the operational conditions within. For this code, that means integrating field testing into the evaluations of new systems and providing prescriptive best practice guidance in conjunction with performance requirements.

Protections for Public Health. This code is a combination of performance testing and prescriptive guidelines for venting, screening, and retention time of composted excreta and diverted urine to create easy-to-follow requirements and clear inspection points that protect public health even in the event of system failure and poor owner maintenance. The Model Code mandates that in the event of a system or maintenance failure, watertightness, screening, and venting requirements prevent public health threats. Composting toilet systems must maintain unsaturated aerobic decomposition conditions, their temperature must stay within the range of beneficial decomposing organisms, and decomposition must occur for at least one year, which is outside the survival time of pathogens.

Environmental Protection. Urine diversion can significantly remove the majority of nitrogen in domestic wastewater, and composting toilet systems can further reduce nitrogen. These systems offer high performance pollution reduction at low cost. This code brings new, lower cost options for environmental protection to homeowners.

Innovation. This code enables the installation of transformative technologies by creating a code with clear inspection points to safeguard public health even in the event of the failure of both established and novel designs. The output of the installations of a composting toilet system are subjected to biological field testing and verification to assure performance. Our hope is that this code will help launch a vigorous domestic industry in composting toilets and urine diversion systems.

Model Code - 2023 Update

The Recode Model Code for Composting and Urine Diversion Toilets is a public domain code first produced in May 2014 and revised in June 2015 and November 2023. The goal of the Model Code is to encourage the growth of an ecological sanitation industry through harmonization of urine diversion and composting toilet regulation across jurisdictions and code standards bodies.

The Model Code was integrated into ANSI/IAPMO WE Stand 2017, which was revised and updated in 2020 and 2023. Major additions from the WE Stand process include a supplementary inspection checklist (2020); guidance for urine land application through nutrient management planning, a urine tank volume calculator, and numerous language requirements (2023).

The 2023 update to the Recode Model Code attempts to integrate innovations from emerging code standards, such as WE Stand 2023 and ISSO NTR 3216, without relying on copyrighted language or proprietary developments unique to these standards. The Model Code includes all updates drawn from public domain sources, such as EPA testing standards and publicly available research. Where WE Stand or NTR 3216 updates include novel requirements, all attempts have been made to create parallel requirements in the Model Code that reflect the intent, but not the language, of WE Stand or NTR 3216.

Additionally, the 2023 edition separates the composting toilet and urine diversion sections, rather than intermingling them, as is done in the original Model Code and WE Stand. The intent of this change is to separate out urine diversion systems connected to plumbing drainage systems from dry toilet systems, as is done in NTR 3216.