The issue becomes where to draw the line. In the case of air quality alerts, are rides canceled when the air quality reaches “Unhealthy for sensitive groups”? “Unhealthy” (with the recommendation that outdoor activity be limited, perhaps this means reducing the length of your ride?), “Very Unhealthy”? Keep in mind that if conditions are not favorable for you, you can opt not to ride. In addition, the leader has the option not to ride, but if one signs up to lead a ride, they should honor their responsibilities. Such is the spirit of the Club cancellation policy. The key here is that personal responsibility and discretion of each individual rider has to be considered. In my opinion, a much greater risk to us is traffic, but that is a risk that we have to reckon with each time we clip in.