I recently cleaned my home's air filters and discovered a significant increase in well-being.
Previously, staying at home during the weekend for more than 1-2 hours resulted in fatigue and dizziness,
whereas being outside or at work during the weekdays (indoor environment with commercial/industrial-grade HVAC) did not.
My carbon monoxide detector couldn't find anything so CO was not likely the cause of the problem.
Conditions also improved when the heating was turned off.
After the cleaning of air filters (edit: there was a lot of unknown black material stuck in the filters during the clean),
no such fatigue nor dizziness occurred, even with heating turned on.
So based on this experience, I suspect the difference has something to do with the concentration of leaked natural gas compared to air flowing through the filters into the house.
Is there a recommended method and tool to detect natural gas, or any more accurate cause of the problem, so that I can better detect and prove such a phenomenom (something causing unusual fatigue and dizziness over time) in any given location, especially when changing air filters myself is not an option?
Best Answer
Natural gas has a chemical called Mercaptan the human nose can detect this at ~1 part per billion so probably not that.
Excess carbon dioxide the stuff you exhale can cause your symptoms and newer tightly sealed homes can allow the carbon dioxide to build up.
You may have make up air on your furnace a small amount drawn in from outside.
Because of dirty air filters your make up air was not being drawn in, or not in sufficient quantities to purge the excess carbon dioxide.
Clean filters equals more air exchanges in the furnace and if there is a make up air line drawing in some fresh air more air reducing the excess carbon dioxide. If no make up air the higher air flow mixing the air in the room.
It could just be cabin fever as one comment suggests but I would also look to air quality.