Conducting an Infectious Disease Risk Assessment
calendar icon April 26th, 2021
author icon Jeff Pajot
Conducting an Infectious Disease Risk Assessment

During the COVID-19 pandemic many things have changed in our society, but when it comes to occupational health and safety, not much is new.


Employers and supervisors must still have a risk management program in place to recognize, assess, control and evaluate risks in the workplace. All workplace parties have a role, and everyone must do their part to successfully identify occupational health and safety risks and implement controls to mitigate these risks to keep people within acceptable levels of health and safety risk.


What is a Risk Assessment?


A risk assessment is a written process to identify hazards, determine risk and establish controls to mitigate risk. Risk assessments also encompass risk of infectious diseases such as COVID-19. Although the Occupational Health and Safety Act (OHSA) does not say explicitly that you must conduct an Infectious Disease Risk Assessment (IDRA), this is implied in OHSA sections 25(1) and (2) where it states that procedures must be carried out, workers must be acquainted with any hazard, information, instruction and supervision must be provided to a worker, and the employer must take every precaution reasonable for the protection of a worker.


Conducting risk assessments is a part of a larger Health and Safety Management System (HSMS). The purpose of the HSMS is to provide effective systems for managing workplace health and safety risks as well as continuous improvement in occupational health and safety.


So, the question is not “should you complete a risk assessment?”, but how do you complete a risk assessment for infectious diseases like COVID-19.


Conducting Infectious Disease Risk Assessments (IDRA)


Public Services Health & Safety Association (PSHSA) has developed a new Infectious Disease Risk Assessment (IDRA) tool which has been designed for use by the broader public sector, including municipalities, school boards, colleges, universities and other public services. The purpose is to identify and assess risks, determine controls and assist organizations in developing an action plan for infectious disease hazard control in the workplace. PSHSA’s IDRA tool is broad enough to include not only person-to-person infection transfer such as COVID-19, but also all categories of infection, including animals, waste, food and insects.


The IDRA should be conducted according to the following guidelines:

  • Take a team approach that is supportive of the Internal Responsibility System (IRS).
  • Appoint a management lead with adequate knowledge to coordinate the completion of the IDRA.
  • Consult with the Joint Health and Safety Committee (JHSC) or Health and Safety Representative (HSR) and all key stakeholders, including front-line staff.
  • Ensure the IDRA is documented and the findings and recommended controls are provided to management for review, approval and action.


The IDRA Tool uses an 8-step assessment to accurately identify and control an infectious disease:

  1)  Identify the task(s) that can cause worker exposure to an infectious disease.

  2) Identify potential risks of exposure – where can exposure occur?

  3) Identify mode(s) of transmission – how can the infectious agent be spread?

  4) Identify existing controls – what is currently being done to reduce the risk of infection?

  5) Identify contributing factors – what specifically will contribute to infection in terms of exposure (e.g. workplace conditions, tasks, environment, nature of the infectious agent, effectiveness of controls)?

  6) Identify applicable legislation and standards (e.g. Public Health Ontario).

  7) Identify the level of risk.

  8) Propose controls to further protect workers.


Furthermore, when proposing controls — especially as they relate to infectious disease — it is important to consider the different types of controls available to effectively address the hazard. In the Hierarchy of Controls, examples of controls from most effective to least effective are as follows:


  • Elimination: requiring sick people to stay at home, locking-down the facility, implementing screening protocols and sending sick people home, face coverings/masks/shields.
  • Substitution: replacing current cleaning chemicals with stronger disinfectants that are effective in eliminating a particular pathogen.
  • Engineering: installing partitions to prevent droplet spread, ventilation that filters virus particles.
  • Administrative: implementing policies and procedures for infectious disease prevention (e.g. cleaning, screening, face coverings/masks/shields, inspections, incident investigation, shut-down, stay home if sick, hand hygiene, cough etiquette, physical distancing, signage).
  • PPE: use of gloves, aprons, surgical masks, respirators if close contact required with infected person. (See PSHSA’s Fast Fact on PPE in Non-Healthcare Workplaces.)


Residual Risk


The IDRA does not end at step #8. It is essential to re-evaluate your implemented controls and conduct a second risk assessment after the proposed controls are implemented, especially when the risk level is rated as “high” or “medium”. It must be determined that the risk was indeed reduced, and workers are reasonably protected. Controls should be evaluated through effective measurement using leading and lagging indicators (e.g. number of visitors screened for COVID-19 symptoms, number of times per day washrooms are cleaned, incident/injury/illness frequency).


Action Plan


In order to be effective, the IDRA must lead to action and so it should be provided to senior management for review and approval. Once approved, an action plan for implementing the proposed controls must be developed and communicated. All staff should be assigned duties and be informed of their responsibility to complete action items. The IDRA should be completed annually, or more often if circumstances change to consider new information.


Although a pandemic like COVID-19 may create fear in some people, actively assessing and analyzing risks of infectious diseases will help to control the risks and lessen the fear that workers and the public may have. We all want our communities and businesses to remain open and vibrant. Visit PSHSA’s COVID-19 Resource Centre for prevention and workplace planning resources, including the IDRA tool, at



Jeff Pajot, CRSP
Health & Safety Consultant


Jeff is a Health and Safety Consultant with the Public Services Health & Safety Association on the Government/Education Sector team and specializing in Parks and Recreation. He has 33 years of experience in Occupational Health and Safety. Jeff completed his Bachelor of Science degree in Kinesiology at the University of Waterloo, specializing in Ergonomics, and he completed his certificate in Occupational Health & Safety from Algonquin College. Jeff is a Canadian Registered Safety Professional (CRSP) and Canadian Certified Ergonomist (CCPE).

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