Per the EPA:

> Upgrading to a filter rated MERV 13 or higher can be especially important during smoky periods to effectively remove fine particle pollution from smoke in the indoor air.

* https://www.epa.gov/wildfire-smoke-course/preparing-fire-sea...

The carbon is for the smell. The EPA also points to this California list, which include "mechanical" types which do not use electronic measures:

* https://ww2.arb.ca.gov/list-carb-certified-air-cleaning-devi...

The main challenge is the resistance to airflow (US: inches w.c.) that can be a problem with for HVAC equipment, which is why you want a large surface area, e.g.:

* https://electronicaircleaners.com/docs/aprilaire_2416_2216_a...

* https://www.aprilaire.com/whole-house-products/air-purifiers...