Spirometry testing for medical surveillance for designated substances during the COVID-19 pandemic

Spirometry tests assess how well the lungs work by measuring the volume of air that is inhaled and then forcefully exhaled, and the rate at which this occurs.

These tests may be performed:

  • in office settings
  • away from workplaces
  • as part of a more comprehensive set of pulmonary function tests

The process of forceful exhalation during testing may spread droplets by the person taking the test. Medical practitioners and associate staff overseeing these tests may be at risk of exposure to COVID-19 if an infected person is tested, even if they have no obvious symptoms of COVID-19 infection.

Because of this risk, some professional organizations have recommended that pulmonary function testing be limited for urgent purposes.

The Ministry of Labour, Training and Skills Development acknowledges the usefulness of this advice in preventing the spread of COVID-19. The ministry also acknowledges the importance of ongoing medical surveillance for workers exposed to designated substances.

Employers must continue to meet their duties to provide workers with the medical examinations and tests in accordance with Ontario Ontario Regulation 490/09 – Designated Substances made under the Occupational Health and Safety Act and the Code for Medical Surveillance for Designated Substances.

An employer who opts to have this testing performed in their workplace must take all precautions reasonable in the circumstances to protect workers involved in providing testing to other workers. Any decision to defer spirometry/pulmonary function testing during the COVID-19 pandemic for public health reasons must be made:

  • by the examining physician, as based on their professional judgment
  • in consultation with the worker

The administration of a respiratory questionnaire is recommended when making this assessment. Any spirometry/pulmonary function testing that is deferred remains legally required and should be performed at the earliest opportunity.


The Ministry of Labour, Training and Skills Development’s Code for Medical Surveillance for Designated Substances (Code) sets out the Medical Surveillance Program requirements for the following designated substances: asbestos, benzene, coke oven emissions, isocyanates, lead (inorganic and organic), mercury (alkyl and non-alkyl compounds) and silica.

It applies to employers that are required to provide for medical examinations required under subsection 20(4) of Ontario Regulation 490/09 – Designated Substances.

Worker participation in medical surveillance programs is not mandatory. In accordance with subsection 28(3) of the Occupational Health and Safety Act (the Act), a worker must consent to participate. It is recommended that the benefits and limitations, if any, of medical surveillance programs be communicated to workers to assist in this determination.

Medical surveillance programs established in accordance with this Code may assist in the detection of exposure-related adverse health effects for appropriate medical follow-up, including removal from exposure, and may direct the need for immediate evaluation of primary exposure control measures. They help protect the health of workers by:

  • Providing direction to examining physicians concerning the medical examinations and clinical tests used in the determination of a worker’s fitness for working in exposure to the designated substance;
  • Identifying workers with conditions which may be aggravated by exposure to the designated substance and establishing a baseline measure for determining changes in health;
  • Evaluating the effects of exposure to the designated substance on workers;
  • Enabling remedial action to be taken in the workplace when necessary; and
  • Providing health information targeted to the individual worker.

In accordance with section 29 of Ontario Regulation 490/09, physicians conducting medical examinations or supervising clinical tests of a worker are governed by this Code in making a determination of whether a worker is fit, fit with limitations or unfit to continue working in exposure to the designated substance.

Physicians conducting medical examinations and/or supervising clinical tests of a worker must be competent to do so because of knowledge, training and experience in occupational medicine.