Smoke Readers & Zoning Ordinances

Welcome to Our Series on Regulating Smoke


One thing I’ve noticed as a city attorney over the years – where there’s smoke, there is likely to be fire, but also heated complaints to city hall. Hard to tell which burns hotter from some of the meetings I have attended. Smoke can be the result of residential heating, recreational activities or industrial activities. Whatever the source, smoke is a frequent topic of city regulation.

This article is the final segment in a 4-part series of LMC Codification blog entries on city ordinances and smoke regulation. This week's focus is on zoning ordinance standards regulating smoke and ambient air standards.

Smoke in Zoning Ordinances

Cities commonly regulate smoke as part of their zoning ordinance. Frequently, these rules are found in a “performance standards” section that regulates all types of nuisance conduct that may result from uses, such as noise and vibrations.

In reviewing these ordinances, I find that cities generally follow three methods of smoke regulation, including the Ringlemann chart, adoption of current Minnesota Pollution Control Agency (MPCA) standards and use of something called “State of Minnesota Pollution Control Standards, Minnesota Regulation APC 1 15.” For this blog entry we will discuss each method in detail.

Minnesota Pollution Control Standards:

Many cities simply adopt MPCA standards as their performance standards for zoning uses. Typical language is as follows:

SMOKE AND PARTICULATE MATTER. The ambient air quality standards of the Minnesota    Pollution Control Agency shall apply to the release of airborne materials.

Generally, MPCA standards are found in the Minnesota Rules ch. 7009 (available at this link: https://www.revisor.mn.gov/rules/?id=7009). The MPCA standards appear to be based on federal standards. According to the MPCA, cities may adopt more stringent local standards for smoke.

The Ringlemann Chart:

Ringlemann was a French scientist born in 1861. His practice of measuring smoke by using cards of various colors from white to black is still used today. More his smoke chart can be found on the CDC website at: http://www.cdc.gov/niosh/mining/pubs/pubreference/outputid330.htm.

Ordinance provisions using the Ringlemann chart typically look like this:

Smoke: Measurement of smoke shall be at the point of emission. The Ringlemann Smoke Chart published by the United States Bureau of Mines shall be used for the measurement of smoke. The following table indicates for the various zoning districts the acceptable level of smoke emissions. These provisions, applicable to visible gray smoke, shall also apply to visible smoke of a different color but with an equivalent apparent opacity.
Zoning District Maximum Level of Emission Exception
R-1, R-1x, R-2, R-3, R-4, and Developing Residential Areas Ringlemann No. 0 None
B-1, B-4, CDC, M-3, MRD Ringlemann No. 1 Smoke of a Shade Equal to No. 2 on the Chart may be Emitted for a Total of Eight Minutes during any one hour period.

Cities using the Ringlemann chart are using a legal and legitimate standard for measuring smoke. However, cities using the chart may run into practical difficulties related to enforcement should they have a true smoke problem use on their hands.

The problem with the Ringlemann chart is that it is speaking a different language from the current MPCA standards. Smoke at Ringlemann No. 1 does not automatically equate to a similar smoke measurement under MPCA standards. As a result, it may be difficult for a city to understand (without expensive professional evaluation) how their standards relate to mandatory state standards.

In addition, cities needing to take a Ringlemann measurement may have difficulty finding a suitable “expert” trained in measuring smoke this way. Smoke measurements these days are typically obtained by certified “smoke readers.” Smoke readers are generally trained to measure smoke using MPCA and federal measurement standards. This is because most smoke reading programs are designed to help people become “in-house” smoke readers for private industries that may be facing federal penalties for emissions violations.

Minnesota Regulation APC 1-15

A substantial number of cities also have this language adopting Minnesota Regulation APC 1-15 as their standard for smoke regulation:

The emission of smoke by any use shall be in compliance with and regulated by the State of Minnesota Pollution Control Standards, Minnesota Regulation APC 1-15, as amended.

This language is potentially problematic because it is outdated. These standards have not been current since the mid-80’s and have been superseded by the current Minnesota Rules. If faced with an enforcement issue, the city may have difficulty obtaining a copy of these standards and reading them in concordance with current standards. In addition, certified smoke readers might not be familiar with these standards.

Conclusion

This concludes our 4-part series on smoke regulation. Far from being an ephemeral topic – smoke is a frequent and lasting concern to Minnesota cities. Ordinances on smoke touch many areas of resident lives – from business endeavors to private recreational uses. Recent changes in technology – related to both methods of heating (such as the new popularity of outdoor wood boilers) and methods of measuring smoke may prompt cities to review their ordinances. In addition, recent law changes related to tobacco products regulation may require ordinance redrafting.