Illinois Code Update

All politics is local. On a national level, model codes are heavily debated and managed in a detailed manner. However, local adoption and modification is a different story. Local and state agencies typically do not have the resources to give code development the full support it requires and frequently defer to a model code for the bulk of their regulations while adding some changes for local needs. Illinois maintains its own plumbing code¹ and in the last Illinois Register of 2018² (Volume 42, Issue 52), there were some proposed changes that caused quite a stir among ASSE International members:

1. Removal of ASSE 1017 compliant temperature actuated mixing valves for hot water distribution systems,
2. Changing the definition of hot water to 160°F (71.1°C) and above, and
3. Requiring the hot water distribution temperature to be 160°F (71.1°C) throughout the system up to 12in (30.5cm) away from the fitting for non-residential applications.

These proposals stem from several deaths over the past few years that have been linked to pneumonia due to Legionella pneumophila contracted at the Illinois Veterans Home in Quincy, Ill. While there are several means of preventing opportunistic pathogens from invading our water supply, raising water temperature to destroy the cell walls (i.e. scalding bugs) is a common practice.

Many agencies and manufacturers, including ASSE International and the International Association of Plumbing and Mechanical Officials (IAPMO), have submitted public comments to the Illinois Department of Public Health, and have given public testimony during the Feb. 4 meeting in Springfield, Ill. All comments and testimonies underscored the conclusion that these proposals were inappropriate. However, let’s look at this in a positive light – at least this has opened an industry-wide conversation about where appropriate changes to the Illinois Plumbing Code can be made.

The primary argument for removing the ability to install an ASSE 1017 compliant valve is to assist with pathogen prevention. Typical residential installations set an ASSE 1017 compliant master mixing valve at 120°F (49°C) for hot water distribution within a home, resulting in a slightly reduced temperature at the point-of-use (POU). Downstream of that would then be an ASSE 1016 / ASME A112.1016 / CSA B125.16 compliant automatic compensating valve for individual showers and tub/shower combinations. Homes that have a bidet or a fast-filling fitting for a bathtub require a ASSE 1070 / ASME A112.1070 / CSA B125.70 compliant water temperature limiting device, but those are not the norm.

Where the Illinois code proposals are correct is in removing the ability to use an ASSE 1017 valve for controlling point-of-use temperature. ASSE 1017 valves are not intended for protection against scalding or thermal shock; they are only intended for temperature control where the inputs have a steady state temperature. ASSE 1017 devices can adequately respond to changes in incoming temperature when it increases at a rate of < 1°F/min (<0.55 °C /min) – far less than what is required to protect against thermal shock.

Regarding changing the definition of “hot water” to 160°F (71.1 °C) for non-residential use, such a change would be a large shift in practice. Water at that temperature might prove dangerous for users who do not have downstream mixing valve capabilities already installed, and for anyone who performs plumbing maintenance. One appropriate alternative is to use an ASSE 1017 valve to assist with killing opportunistic pathogens – elevate the water temperature for a given amount of time and then mix it down to an appropriate design temperature for the hot water distribution system. Time and temperature are both critical for disinfection, as the same scalding concepts for exposure to the cells on your skin apply to the cell walls of the bacteria.

At the time of writing, the next opportunity to engage is at the Plumbing Code Advisory Council (PCAC) meeting on March 12 at the Illinois Department of Natural Resources, where there will likely be more discussion on these and other comments. The IDPH will need to formally respond to each of the comments submitted, just like most other regulatory processes, and then the public has another opportunity to respond. The dates for the next steps have not yet been set, but we will be paying close attention.

1. Illinois Administrative Code, Title 77: Public Health, Chapter I: Department of Public Health, Subchapter: Water and Sewage, Part 890: Illinois Plumbing Code. http://www.ilga.gov/commission/jcar/admincode/077/07700890sections.html
2. Illinois Register, 2018, Volume 42. https://www.cyberdriveillinois.com/departments/index/register/18register.html