September 5-12, 2005

Tougher limits, updated dispersion models among highlights of new Ontario air rules

The Ontario government has finalized a new, comprehensive air pollution regulation which will update the regulatory framework that has been in place in the province for over 30 years. Regulation 419/05 will replace the old Regulation 346 and will set new or updated air quality standards for 40 pollutants (up from the 29 initially proposed). Some limits will be more stringent than previously and seven substances will be subject to regulatory limits for the first time.

The new regulation, which comes into effect on November 30, 2005, will also provide a faster, risk-based approach to implementing new air standards and modernize air dispersion models in order to give a more accurate assessment of health and environmental impacts. The new regulatory framework incorporates the remaining three components of a five-point action plan for cleaner air, introduced by the government in June 2004 (ELW June 28, 2004).

Regulation 419/05, Air Pollution - Local Air Quality incorporates new or updated standards for 40 pollutants. Those that have become more stringent will be phased in over the next five years to give industry time to plan for and meet the tougher limits. The new standards will apply to all industrial facilities by 2010.

The standards are based on health and environmental impacts, and will be used to assess and manage local impacts from industries on surrounding neighbourhoods and communities. The new standard for cyclohexane, for example, is 16 times stricter than the previous standard. The substance, commonly used in plastic and resin manufacturing, has been associated with fetal developmental effects in animals. A complete list of the standards may be viewed on the Ministry of Environment (MOE) Web site,

At the same time, the government has initiated the public consultation process on the development or updating of air quality standards for an additional 12 substances. Air Standard Information Drafts for 12 new substances have been posted on the Environmental Bill of Rights registry for a 120-day comment period ending December 27, 2005. Each of these drafts summarizes key toxicological and risk assessment information and reviews other jurisdictions' standards and guidelines for the particular substances. These peer-reviewed scientific studies and other relevant toxicological information will form the basis for the future proposed air quality standard(s) for the 12 substances.

They include: n-butanol (registry reference No PA05E0020); chlorine dioxide (PA05E0021); chloroethane (PA05E0022); 1,1-dichloroethane (PA05E0023); ethylene oxide (PA05E0024); isobutanol (PA05E0025); methyl chloride (PA05E0026); phosphoric acid (PA05E0027); propylene (PA05E0028); sulfuric acid (PA05E0029); total reduced sulfur (TRS) compounds (PA05E0030); and 1,2,4-trimethylbenzene (PA05E0031).

The second major provision of the new regulation will, over time, phase out the province's current air dispersion models and replace them with the U.S. Environmental Protection Agency models, which will help give a more accurate assessment of health and environmental impacts. The air dispersion models are used to assess industries' compliance with provincial air standards.

The MOE is phasing in the requirements for new models by focusing first on sectors with air emissions that potentially present a higher risk to human health and the environment. The first group of sectors will be required to comply with the new standards using the new models by 2010; the second group by 2013; and the remaining sectors by 2020.

Regulation 419/05 also puts in place a new approach to set and implement air quality standards more quickly. A risk-based decision-making process to evaluate barriers to compliance is outlined in the regulation and will allow for site-specific considerations of technical limitations for industry, costs, risk to the local community and public transparency. If necessary, the process allows site-specific alternative standards to be set based on technology that takes into consideration timing issues, technical limitations and/or economic barriers.

The local community will be provided an opportunity for input into the decision-making process, and facilities will have to demonstrate that they are doing their best to reduce their concentrations. They will also have to tell the Ministry and the public how they will improve their emissions over time. The site-specific alternative standards will be periodically reviewed to ensure continual improvement towards achieving the effects-based standard.

The regulation, including a summary of issues raised during the public comment period and links to relevant documents, may be viewed on the EBR registry, reference No RA05E0008.

The first two components of Ontario's action plan for cleaner air are addressed by Regulation 194/05, which has been finalized and posted on the EBR registry. Regulation 194/05, Industry Emissions - Nitrogen Oxides and Sulfur Dioxide, which came into effect in late May, applies stricter limits for nitrogen oxides (NOX) and sulfur dioxide (SO2) to seven large industrial sectors: iron and steel, cement, petroleum, pulp and paper, glass, carbon black, and base metal smelting. Limits continue to be in place for the electricity sector.

This regulation addresses the plan's second component by requiring significant NOX and SO2 emissions reductions by 2010 and further reductions by 2015. This will result in a 21% reduction in NOX emissions from 1990 levels and a 46% reduction in SO2 emissions from 1994 levels for capped industries. The regulation complements the programs Ontario already has in place to reduce air pollution created by the transportation and electricity sectors.

The EBR registry posting of this regulation includes a summary of issues raised during the public comment period, the Ministry's response and the resulting modifications made to the final draft (reference No RA05E0002). The registry may be accessed through the MOE Web site,

Table of Contents  | Top of Page

  Ecolog Network