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1. Introduction
   • VOCs and air pollution
   • VOCs and asphalt
2. Code of Practice objectives
3. Summary of results for 2023
4. Progress since first reporting period (2017)
5. Conclusion & Next steps
6. Contact

List of tables

Table 1: recommended VOC limits

Table 2: Quantities of liquefied asphalt manufactured in 2023 and resulting VOC emissions

Table 3: Products manufactured in 2023 exceeding the Code’s recommendations and resulting VOC emissions

Table 4: Total quantities of liquid asphalt products reported in 2017, 2019, 2021 and 2023 and resulting VOC emissions and VOC EI

List of figures

Figure 1: progress of emission intensity towards meeting the 2023 target

1. Introduction

On February 25, 2017, a notice of the issuance and publication of the Code of Practice for the Reduction of Volatile Organic Compound (VOC) Emissions from Cutback and Emulsified Asphalt (the Code) was published in the Canada Gazette, Part I. This Code includes reporting every 2 years from cutback and emulsified asphalt manufacturers. The objective of this progress report is to provide a summary of the data submitted by industry in 2024, for the 2023 calendar year. This is the 4th and final report following publication of the Code. In this report, results from the first progress report, covering 2017 activities (in other words the baseline year), are compared to the 2023 data to assess progress towards meeting the Code’s objectives.

VOCs and air pollution

VOCs are volatile organic compounds that participate in the formation of ground-level ozone through complex reactions with nitrogen oxides (NOx), in the presence of sunlight. They also contribute to the formation of particulate matter via complex chemical reactions involving emissions of other smog precursors, including sulphur dioxide (SO₂), NOx and ammonia (NH₃).

Particulate matter and ground-level ozone are the 2 principal components of smog. Smog is an air quality issue that poses serious health and environmental concerns in Canada. Particulate matter and ozone can be transported by prevailing winds over long distances, making them not only a local urban issue but also one that can extend into many smaller communities and rural areas. The 2013 Canadian Smog Science Assessment (co-authored by Environment and Climate Change Canada and Health Canada) concluded that both particulate matter and ground-level ozone need to be treated as having no safe levels.

VOCs and asphalt

Cutback asphalt and emulsified asphalt are liquefied asphalt products used in various road construction, maintenance and repair applications, such as plant mix, road mix, surface treatment and maintenance mix. These products are prepared by mixing asphalt cement with a petroleum solvent to produce cutback asphalt, or with emulsifiers and water (and sometimes a small amount of petroleum solvent) to produce emulsified asphalt. During paving operations, the petroleum solvent or the water evaporates after the liquefied asphalt is applied, leaving the asphalt cement behind. This evaporation of petroleum solvent results in VOC releases into ambient air. The use of cutback asphalt generates more VOC emissions than emulsified asphalt, as it contains larger quantities of petroleum solvents.

As of 2016, many jurisdictions in Canada and the United States have adopted practices to reduce VOC emissions from this sector. These practices involve either restrictions on the use of cutback asphalt during the ozone season (typically the summer months); a prohibition of the use of cutback asphalt throughout the year; or limiting the VOC content in cutback and emulsified asphalt products.

2. Code of Practice objectives

The objective of the Code is to protect the environment by reducing VOC emissions from the liquefied asphalt sector by at least 40% over a 6-year period. The Code describes recommended practices that should be implemented to meet the Code’s objectives, including maximum VOC contents by volume of cutback and emulsified asphalt products during and outside of the ground-level ozone season (table 1). This season runs from May 1 through September 30. There are no recommended practices in the Code for emulsified asphalt products used outside of the ozone season.

Table 1: recommended VOC limits

Additionally, the Code recommends manufacturing, importing, selling and using low VOC-emitting alternative products instead of cutback asphalt, and promotes the consideration of low VOC-emitting products during contracting discussions. Consideration should also be given to adding a commitment to follow the Code in contracts issued for paving or maintenance operations in Canada.

3. Summary of results for 2023

The following summary presents the information received for the 2023 reporting period. Please note that due to rounding, figures throughout this document may not sum precisely to the totals provided, and percentages may not exactly reflect absolute values.

A total of 9 liquefied asphalt manufacturers submitted reports to Environment and Climate Change Canada for the 2023 calendar year. According to the data, 271.1 kilotonnes (kt) of liquified asphalt were manufactured, which resulted in 4.7 kt of VOC emissions following application.

As indicated in Table 2, most liquefied asphalt produced in 2023 was emulsified asphalt, accounting for 90% of the total manufactured. In contrast, cutback asphalt represented only 10% of the total quantity but was responsible for 46% (2.2 kt) of the resulting VOC emissions, a decrease from 55% in 2021.

Table 2: Quantities of liquefied asphalt manufactured in 2023 and resulting VOC emissions

Reporters provided data for 224 liquefied asphalt products manufactured in 2023. The data required to evaluate compliance with the Code’s recommendations was provided for 214 products. Of these, 181 products met the Code’s recommendations while 33 did not. The 33 products that exceeded the Codes’s recommendations represented 8% of the total quantity of liquefied asphalt manufactured in 2023 and 46% of the total VOC emissions (table 3).

Table 3: Products manufactured in 2023 exceeding the Code’s recommendations and resulting VOC emissions

4. Progress since first reporting period (2017)

Not all manufacturers are captured by this report and some manufacturers did not report for each reporting period. As such, emission intensity (EI) expressed in kg per tonne of asphalt is used to evaluate the progress towards meeting the Code’s objective, rather than total emissions.

The following table provides the total quantities of liquid asphalt products reported for 2017, 2019, 2021 and 2023 with the resulting VOC emissions, VOC EI and VOC EI percent reduction for each year.

Table 4: Total quantities of liquid asphalt products reported in 2017, 2019, 2021 and 2023 and resulting VOC emissions and VOC EI

The graph below shows the overall EI of liquefied asphalt products in 2017, 2019, 2021 and 2023, along with the 40% reduction target for 2023. For comparison, a trendline representing the progress for manufacturers who reported all four years has also been added.

Figure 1: progress of emission intensity towards meeting the 2023 target

5. Conclusion & next steps

In 2023, the VOC emissions intensity (EI) of liquefied asphalt products manufactured in Canada was 17% lower than in 2017. This reduction falls short of the Code’s target of a 40% decrease over the same period.

Emulsified asphalt, which contains little to no VOCs, is a viable alternative to VOC-based cutback asphalt that is widely used in the paving industry. In 2023, it accounted for 90% of the liquefied asphalt reported to be manufactured in Canada, and 54 % of VOC emissions from liquified asphalt products. Cutback asphalt, on the other hand, despite making up only 10% of production, contributed the remaining 46% of the sector’s VOC emissions.

To support further progress toward meeting the Code’s target, ECCC will engage with the paving industry to identify where cutback asphalt is still being used and address barriers to transitioning to emulsified products for these applications. The department will also consult with key industry stakeholders, including procurement decision-makers and paving companies, on strategies that could be put in place to accelerate progress towards meeting this Code’s objective.

In addition, in 2025, ECCC will carry out a compliance promotion campaign aimed at municipalities to ensure procurement officials are aware of the Code’s recommendations and encourage them to include its requirements in paving contracts.

6. Contact

If you have any questions regarding this report, please contact us by email at Produits-Products@ec.gc.ca.