We have a nearby factory polluting air with formaldehyde and when the wind occasionaly brings it to us we sense the smell and are forced to close the windows to not let it in. When the wave subsides we can open the windows again. It would be convenient to have an outdoor sensor giving an alarm when the level starts rising to give us time to close the windows before it starts to get in and notifying us when the level is back to normal so that we can open the windows again.
Are there such solutions available on the consumer market? I know there are industrial solutions but those are expensive and not available to individuals.