Wife just popped by, asked me not to ride my MB to work (.75 mile, one-way) 'cause of the 151 number media's put on current air quality here, now that yesterday's front has pushed out the HOT humid air we've suffered with for weeks for much cooler (but maybe toxic?) air.



So just how bad is too bad for us to ride? Anything meaningful for age groups?

I'm mid-70's, commuting doesn't get me breathing hard but I do tend to huff & puff when I'm riding for recreation, which I fully expect to do tomorrow when I have more time before my afternoon's second half-day-at-work this week.

I'm in Southern California, the land of brushfires. If I can smell the smoke, or if ash has reigned down on my car's windshield overnight I won't go out for a bike ride or any other aerobic activity.(the windshield is dark against the car's interior in the AM and the ash is white). I've never had a problem interpreting air quality due to fires with that method.

https://www.airnow.gov/sites/default...re_02_14_0.pdf

50 has enough of an effect on me that I start wondering what the AQI is. At 150, I'm inside popping prednisone.

Its 115 where I am right now and it was bad enough for me to drive to work this morning instead of riding in(7mi). Not sure what the cutoff is, but apparently 115 is above it, if I have a car sitting in front of me!
I guess as consolation I can be happy I am not in the worst of it in my region.
A couple hours north in S MN is 170, Green Baw WI is 190, Cedar Rapids IA is 156, MPLS is 160,etc.


After a couple weeks of unrelenting high heat and high humidity, its a nice temp and terrible air.
Oh well- there is always tomorrow!

See the chart in my link above. 115 is considered unhealthy for sensitive groups,

I'm in NorCal and we get our share of smoke days. I have found that Purple Air is better for tracking air quality, I always use the LRAPA conversion, and generally I won't ride outside if it's over 150. But I have no particular lung/breathing issues.

The advantage of Purple Air over Airnow.gov, for me, is the sheer number of sensors. It allows me to determine where exactly the smoke plumes may be, how they may be moving, etc, and the data are in real time. A couple years ago, we used the data to revise a route for the Monthly C&V ride, heading North into clear air rather than our usual route, where the air was bad.

Surely there has to be an easier source than a 20 page pdf.

I'm vaguely remembering Canada has the best smoke map, anyone have a link? I wonder if it's headed our way.

I usually only see those warnings after going for a couple hour ride. I don't know what they mean.

Don't you have an Iphone? Just open up the weather app and scroll down until you see the air quality section. Click on that section and it opens to an air quality map. You don't have to wait till your wife sees it on a news show and tells you to stop riding.

The chart appears in the first couple of pages.

I bought one of their sensors. It was remarkable to watch what would happen when the yurt people on an adjacent properly would fire up their wood stove. I think they enjoyed incinerating wet phone books.

Which one did you get? It's almost important enough to me to spend that much on a sensor. I never thought about tracking our neighbor's ridiculous burning activities.
Our backyard neighbor used to burn wood in the middle of summer, even on hot days. I fantasized about renting a firetruck and dumping water down their chimney. At that time, we used an attic fan for cooling. It worked pretty well until they covered the neighborhood in partially combusted wood smoke. Fortunately, the person who liked to make smoke is gone now.

Here's Purple Air's map of the US today. I'm gonna guess there are wildfires in Saskatchewan, and the smoke plume is blowing in to the Midwest from there. Probably gets in without paying the tariff.




Weather Underground's 'Wundermap' has an Air Quality layer that I'm pretty sure uses the Purple Air sensor grid, but there are also standalone apps that give you access to the same data.

I remember a couple years back, watching as the numbers for where we live in San Mateo go from green to yellow to orange as the wind shifted and smoke from the fire in Big Basin crept up the Pacific side of the Santa Cruz mountains and then blew in through the Crystal Springs gap. It had been a warm day, so all the windows were open. When it hit 100, we closed everything up.

Everyone's different, of course.

Grew up in the SoCal region, back when. There were certainly days when the smog (or fire smoke) was hazy enough that it could be smelled. On those days, I skipped the "heavy lifting" type activities and tried to stay indoors as much as possible. But then, I've never had asthma or allergies, and generally have been able to ignore the sort of limitations on lung exposure most others have had to worry about.

That said, generally over ~100 AQI is when I really start paying attention. On a sub-1mi jaunt on a bicycle, I wouldn't have any trouble simply taking it easy and ensuring I get there without bad impacts on the lungs. Still, the AQI means the stuff's in the air, and any breathing is going to be inhaling the particulates and compounds. No way around that unless you have a respirator on.

I think the AQI system generally suggests that anything over 50 is where people should begin to worry, particularly those with "lung" challenges, those without solid cardiovascular, the aged, etc. So, yeah, generally speaking 150's one of those measurements that ought to concern most people.

I got the Flex. So far, it has worked really well.

WU has PM 2.5 and PM 10 numbers on the wundermap. Is that actually usable?

For wildfire smoke, I'd just use the PM2.5. I believe that's what's indicated. I don't know if there's a conversion applied. Comparing Purple Air and WU, the numbers near me are currently within one or two units, while the uncoverted PA numbers are about 15 units higher.

Thanks, I was confused because I thought our aqi was less than 30 and the PM 2.5 is 88. But it turns out our AQI is 80.

I thought AQI = 2.5 pm index

Here in California's elbow we frequently get smoke from forest fires in late summer filling the valley, and I think most of us don't ride if it's beyond remind-you-of-camping level. That's somewhere in the orange level. But the AQI doesn't tell you specifically what's in the air.

Back in the before-covid 2010's there was one particular fire driven by unusual weather that blew smoke into San Francisco and the bay area, which is rare. The precious baby tech bros bought up all that year's available N95's. Since then, that level of solution sometimes comes to mind. But I've never actually done it.

The AQI is a composite index. It was pretty fast to look it up but I think the explanation is better just left as extra credit if you care Technical Assistance Document for the Reporting of Daily Air Quality | AirNow.gov

10 minute average, over the entire continental United States, doesn't mean much when the air in your face is closer to an AQI of 200 than 0.

I had a neighbor once who liked to burn stuff too. First time I noticed it was when he lit off an old tarpaper shed on the corner of his property that was upwind of mine.

Years later some fireworks he'd set off caused a power outage when they shorted a transformer located at the corner of his property.

We faced off at 2:00 AM out in the street, I knew by then it was beyond time to move.