Particles and gases: different control questions

Define the question before choosing equipment

A room can have airborne particles, a noticeable smell, settled material and an ongoing outdoor source at the same time. Before asking “Which filter fixes this?”, identify which problem is being addressed and how the result will be evaluated. Household air-cleaner selection, restoration work-area control and building re-occupancy are separate decisions.

Health Canada’s household guidance describes particle removal and notes limits for gas removal. Read the actual device information: a high particle-removal rating should not be interpreted as a rating for every gas or odour. Labels, maintenance requirements and the room in which the device will run all matter.

Keep ratings connected to their purpose

Do not compare a marketing “covers up to” area, nameplate airflow and CADR as though they are the same measurement. Ask which setting produced the rating and whether that setting is practical for the room and use. Noise can affect how long a device is actually operated, so clarify the relevant operating setting.

Use the worksheet for arithmetic only

The airflow worksheet calculates volume and an ACH assumption that you supply. It does not recommend an ACH for your household, identify a contaminant or size a negative-pressure enclosure. Its output is a question to bring to the responsible professional, not a purchase specification.

If equipment is proposed for restoration, ask for the stated purpose, placement, exhaust/air path, affected work boundary and verification method. Keep manufacturer performance information with the project record rather than relying on a number from an unrelated room calculator.

Ask about ongoing sources and completion

• Is smoke still entering from outdoors or another part of the building?
• What source treatment is included in the work scope?
• What does the equipment remove, and what does it leave unaddressed?
• How will filters/media be handled and replaced?
• What evidence supports the completion or occupancy decision?

References and scope

1. Using a portable air cleaner — Health Canada.
   Household particle filtration and device selection; not a restoration containment design.
2. Improve indoor air quality in your home — Health Canada.
   Source control, ventilation and limits of filtration/testing; ozone generators are not recommended in homes.

Source links checked September30,2026. General guidance and original planning questions do not establish the condition, exposure risk or clearance of a property.