On May 31, 2025, Canada’s new Biocides Regulations come into force, replacing earlier guidance documents with a more robust, unified framework for evaluating biocide performance. In this series of articles, we compare the previous 2020 efficacy guidance with the new efficacy requirements for biocides—highlighting what has changed and what these changes mean for manufacturers.
Many of the requirements outlined in the new guidelines were already followed by Health Canada in practice; however, Health Canada has now clarified these steps by providing detailed explanations. Consequently, while many items mentioned herein are not entirely new, they have been explicitly clarified in the updated guidelines.
Although Health Canada’s new guidance document is more flexible regarding accepted testing quality systems and test methods compared to the US EPA guideline, it strives to align more closely with US EPA efficacy requirements.
Efficacy Requirements Based on Intended Use Areas and Surfaces
In the new Health Canada guidance document, the definition of “Intended Use Areas and Surfaces” has been removed. In the 2020 guidance documents, these areas were defined as follows:
- Domestic (i.e., for use in residential settings);
- Commercial, which includes:
- Industrial/Institutional (i.e., for use in commercial settings such as schools and office buildings);
- Hospital/Healthcare (i.e., for use on non-critical medical devices, environmental surfaces, and inanimate objects in healthcare facilities such as hospitals, dental clinics, and nursing homes);
- Food Processing (i.e., for use in food processing settings such as food processing plants and other commercial food preparation environments);
- Barn (i.e., for use in animal housing settings such as farms, poultry plants, veterinary clinics, and kennels).
In the new guidance, disinfectants are categorized into three major classes:
- Limited: Effective against either Gram-positive or Gram-negative bacteria.
- General: Effective against both Gram-positive and Gram-negative bacteria.
- Hospital: Effective against both groups, including resistant nosocomial organisms.
This classification implies that while the efficacy test requirements for disinfectants intended for commercial, residential, and animal settings remain similar, those for healthcare settings require different criteria.
Classification of Claims Based on Intended Pathogen
Before initiating an efficacy test, it is essential to determine the type of pathogen that the disinfectant claims to destroy (kill), inactivate, or reduce. These pathogens include:
- Germs
- Viruses
- Mycobacteria
- Specific bacterial spores
- Fungi, mould, and mildew
- Other non–spore-forming bacteria (e.g., Escherichia coli)
Health Canada treats non–food-contact and food-contact sanitizers similarly to other claims. To support a claim against a specific pathogen for both food-contact and non–food-contact applications, the sanitizer must meet the general sanitation claim requirements for each category.
In the new guidelines, “germs” is considered a type of general claim; however, its exact definition is not clearly provided. In contrast, the previous guidance defined “germicide” or “kills germs” as follows:
“Disinfectants with efficacy as a general/broad-spectrum disinfectant or a hospital/healthcare disinfectant can be registered with the label claims ‘germicide’ or ‘kills germs’.”
Our understanding is that the “germicide” (or “kills germs”) claim remains unchanged for registrants. If Health Canada were to remove the “germicide” or “kills germs” claims, then “germs” should not have been listed as a general claim.
Required Number of Test Substance Batches and Carriers
The number of test substance batches and carriers required for the various claims remains unchanged except for the “broad-spectrum virucide” claim. Previously, this was a major difference between EPA and Health Canada efficacy requirements. In the new guidance, three batches of test substance are required for testing Limited, General (broad-spectrum), and Hospital/Healthcare disinfection claims, while the number is reduced to two batches for all other claims—including broad-spectrum virucide.
Additionally, the number of carriers for broad-spectrum virucide claims has been reduced from five in the previous guidance to just one in the new guidance. We believe that such a low number of carriers may not adequately demonstrate the reproducibility and repeatability of the test against viruses.
Representative Test Organisms for Each Claim
The new guidance is largely in line with the previous document, except for broad-spectrum virucide. In the updated guidelines, Poliovirus and Adenovirus have been removed from the list of representative viruses. Instead, Rhinovirus, Feline Calicivirus, and Human Astrovirus have been added.
Performance Criteria for Efficacy
The only notable difference between the previous and new guidance regarding performance criteria is in the AOAC Use Dilution Method against S. enterica. This method has been modified to align with US EPA SOP MB-05: Standard Operating Procedure for AOAC Use Dilution Method for Testing Disinfectants.
The new guideline includes a footnote for hospital and general disinfectants stating:
“If tested on the same day, the performance standard of 59/60 must be met. If batches are tested on different days, a performance standard of 58/60 will also be considered, in line with US EPA’s requirement described in SOP MB-05.”
However, the guideline does not clarify that this criterion applies to S. enterica. In contrast, the acceptance criteria for S. aureus and P. aeruginosa are 0–3 positive and 0–6 positive, respectively. Furthermore, in MB-SOP-05-16, the acceptance criteria for S. enterica have been revised from 0–1 to 0–2.