Frequently asked questions

Directives intérimaires concernant la pratique professionnelle en clinique dentaire en situation de pandémie (phase 3)1
(Interim directives on the return to regular activities in dental clinics – the Directives)

Are the Directives final?

No, these are interim measures. Since the situation and our knowledge of the COVID-19 virus is constantly changing, the guidance presented in these Directives could be amended.

We see many Anglophone patients in our practice and we find it really important to have the patient triage questions found in the appendices available in an English version. Will we be receiving the Directives in English?

We are currently working on a summary, which will be translated into English. It will be sent to you as soon as possible. The relevant appendices will be included in this summary.

Patient triage

Dental procedures

If a dental hygienist has produced aerosols by using an ultrasound instrument during a cleaning, does the dentist need to wear a protective gown to examine the patient?

As described in leaflet 4, it is considered safe to conduct an oral exam using standard universal protection measures, without a protective gown.

Certain parents are wondering if they will be able to accompany their child in the treatment room.

A parent can accompany his or her child in the treatment room. Refer to the established protocol in leaflet 4 for the instructions that apply in such cases.

Personal protective equipment

We have been told that the new O2 masks are superior or equal to N95 masks. Have O2 masks been approved?

We have just received a message about O2 masks and are taking the necessary steps to learn more about them and check their certification. We will provide you with more details as soon possible.

There is a great deal of information on social media about P100 masks, which are said to have double filtration power. Can we use these masks in our practice even if they are made for industrial use?

The Directives will be amended soon to allow the use of P100 masks. However, P100 masks will need to be worn with a procedural mask to cover the integrated valve and filter dentists’ exhalation.

We are receiving many offers for KN95 masks. Are these all approved and certified? Have certain suppliers been approved by the Order?

The KN95 masks approved for use in Canada are listed on the Health Canada website. Click HERE to access the list. There are many distributors selling these masks who may contact you, but none of them have been certified by the Order.

Do we have to do a fit test when using KN95 masks, as described in table 4 on page 31 of the Directives?

Certain KN95 masks do need to be tested, but those approved for use in Canada do not require a fit test.

What resources are available to help with fit testing for N95 masks?

There is a lack of reliable resources to conduct fit tests at the moment. Discussions are ongoing with dental equipment suppliers to set up a list of resources. More information will be provided to you once it is available.

We hear about protective gowns of categories 1, 2, 3 and 4. Are there different levels of quality of gowns and standards for each category?

Gowns do seem to be divided into categories by manufacturers, but there are currently no particular standards associated with their use in dental clinics. Washable, handmade gowns are also authorized.

Once the recommended ventilation period has been followed, does an employee need to don a new gown to disinfect the room for the next patient?

Once the aerosols have landed on surfaces, employees do not need to wear a new gown to disinfect the room, unless the patient treated was a confirmed case of COVID-19.

Many of the healthcare workers we see on television wear caps. Yet caps are not mentioned in the Directives. Since aerosols can also land on our head, should we be wearing caps?

After careful review of the situation, it was not found necessary to make this measure mandatory. You can, however, wear a cap if you wish.

Ventilation and filtration

We were not able to consult our ventilation expert before the date of reopening for clinics. As a result, we are not sure whether our clinic complies with the requirements in the Directives. Can we still treat patients?

Yes, but you must first take certain precautions. If you need to perform an aerosol-generating procedure and you do not know the parameters of your ventilation system, you can assume that it provides two air changes per hour (2 AC/H). This means you need to wait 138 minutes from the time you stopped generating aerosols to the start of the next treatment (see table 3 in leaflet 5).

Our expert does not understand the requirements mentioned in the Directives. Who can he or she speak with for clarifications?

The Order has consulted ventilation experts who developed a simplified calculation tool to help you check the air filtration in the rooms you will need.

How does this tool work?

This calculation tool can be used to enter the size of the room and the HEPA filtration rate (AC/H) to determine the required wait time between each patient from the moment aerosol production has stopped.

The formula used in the table is based on six air changes, including one supply of new air – that is, 10 to 15 percent of new air.

You can consult the AHAM website for technical data on many air purifiers. If you know the type of appliance for which you need information, you can find it under the “Brand” tab. Or you can search under “Tobacco Smoke CADR,” which corresponds to the AC/H in the calculation tool.

If you don’t know the number of decibels produced by the appliance, visit this website Bruit et Société (in French only) for comparative data on noise levels

How can I consult the tool to estimate the time between the last aerosol production and the next patient?

To access this tool, if your dental clinic is in red zone, please click HERE.

To access this tool, if your dental clinic is in green, yellow or orange zone, please click HERE.

If you still have questions after consulting this tool, please forward them to

The Directives indicate that closed rooms do not need to be airtight. What does this mean exactly? Instead of a door, can the room be closed off by a curtain that lets air in and out?

The door should generally be made of a solid material (e.g., plastic, polyethylene), which can be cleaned.

Compliance with the directives

Will inspectors from the Order come and check if our facilities and protocols meet the directives?

Inspectors from the Order could come to inspect clinics once the gradual opening has been completed.

1 The Directives were issued by the Ministère de la Santé et des Services sociaux (MSSS), upon the recommendation of a working group set up by the MSSS. The 59-page guidance document was made public on May 22, 2020.