I have spent the majority of my adult life working and playing outside. Which is to say that I’m no stranger to extreme weather.
I’ve trained and raced bicycles in Miami’s concrete jungle mid summer. I’ve climbed south facing cliffs in the New River Gorge in July. I’ve hiked around the Utah and Nevada deserts in the midday summer sun. I even worked inside unconditioned warehouses in the middle of Mexico during the summer.
During and just after high school I installed above ground pools in some of the hottest hollers in West Virginia. I was the young buck of our crew so this meant I had the honor of spreading the sand that forms the pool bottom. This step happens after the pool walls are raised and let me be the first to tell you radiant heat ain’t no joke.
I didn’t think it could get any hotter than working inside the walls of an above ground pool. Then I spent a summer cleaning pools in Nashville, TN and had to reconsider what I understood as “oppressively hot”.
Over all this time working and trying to perform at my limit in extremely hot conditions I can only recall a couple of times when I felt sick from the heat. I’ve always respected hot weather but it’s never really been something I considered when making outdoor plans.
But a couple of weeks ago, that all changed.
When I’m not working behind the computer on business stuff I’m working on building a house for my family. And when I say I’m building a house I literally mean that I alone am building a house. No help, no crews, no boom trucks. It’s just me and my tools.
Why on earth would someone want to take on such an insane and monumental task? I could rattle off a few logical reasons, saving on labor, total design freedom… but here’s the truth.
If you’ve seen the 1999 movie Fight Club you may remember a scene where the main character, Tyler Durden, played by Brad Pitt is driving a car with 3 passengers, 1 in the front (the narrator played by Edward Norton) and 2 in the back (Ricky and the Mechanic), into a head on collision with a semi truck. Just before impact he turns around and has the following exchange…
Tyler: “Guys, what would you wish you’d done before you died?”
Ricky: “Paint a self portrait.”
The Mechanic: “Build a house.”
When I saw that scene 23 years ago I decided that I too, just like the mechanic, wanted to build a house before I died. So, there you have it…
Fight Club made me do it.
But I don’t want building the house to be the death of me. And a few weeks ago it nearly was…
No breeze is no good
It was just another typical hot and humid eastern NC day and I was working inside what will be our laundry room which happens to be on the second floor.
I was sweating profusely and had fully soaked my cotton Carhartt work pants and synthetic Patagonia work shirt. Sweat was puddling on my arms and pouring off my head. I noticed that I was overheating, a familiar sensation that for me starts with a mild headache, queasy stomach and complete loss of appetite.
I knew I’d have to cool down soon so I decided to stop work for the day. But for some reason (that I would only later come to understand) I decided I had to clean up before stopping and cleaning up meant some heavy lifting and several trips up and down the stairs.
My condition deteriorated rapidly.
Get cool now
Heat induced delirium made my memory of what happened vague. But I remember clear as day as I was screwing a sheet of plywood over an open door frame (something I never typically do) the survival instinct kicked in and my inner voice said,
“Dude, you have to get out of here NOW.”
I lurched down the stairs and just before I reached the bottom I realized I was losing consciousness. My heart was racing at nearly 190 bpm, my lower back around my kidneys was burning, tunnel vision had fully set in and sounds were inaudible.
Somehow I made it through the front door and into the open air where a light breeze was blowing. I immediately felt better but was now certain the contents of my stomach where about to be in the front yard. This slight clarity was all I needed to realize that I was in the first stages of a heat stroke.
I stumbled like a drunkard to the water hose, stripped every article of sweat soaked clothing from my body, and proceeded to bask in the cooling glory of tepid groundwater.
Thankfully for the sake of our neighbors we’re building on a lot with plenty of privacy but in all honesty, at that point I would have done the same thing with a crowd of onlookers.
The situation was that dire.
I continued feeling better as the water poured over me but it would take three full days before I felt like I was back to “normal”. I could barely eat during that time and my head was constantly pounding. If I tried to go outside during that time I felt totally vulnerable to the heat, like my internal cooling mechanism was offline.
A hard lesson learned
To take another line from Fight Club, I’d just had a near life experience. One of those moments that makes you truly appreciate how fortunate you are to not feel like death is knocking on your door. These are precious moments that we have to learn from and boy did I learn a lot about what I experienced that day, from what caused my condition to how I’d be able to manage continuing work in it.
So what was the root cause of this heat related illness and why hadn’t I experienced such distress in previously? Quite simply a lack of moving air inside the house. In nearly every other previous instance I had some breeze to aid in cooling my body.
When I was finally able to return to the jobsite I took note of one of the temperature gauges I keep around. The air temperature inside was 98° which is obviously hot but not insanely hot. However, the relative humidity inside the jobsite was 82% and there was no breeze or moving air.
This meant that I’d been working in an environment with a heat index of a staggering 151° and a wet bulb temperature of 93°. According to climate scientists from NASA the human body can withstand a maximum wet bulb temperature of 95° for about 6 hours. I’d been working 4 hours already. Time was not on my side.
Those 2° would have bought me another couple hours but it doesn’t take a scientist to figure out what my body already knew and was desperately trying to tell me… if you lose consciousness in here we’re going to die. We don’t want that. So get outside NOW.
Don’t be scared. Just be smart.
I don’t want to come across as alarmist because there were some unique environmental factors that made my situation very different from what was going on just outside. Mainly that lack of moving air inside the house. I have since learned that addressing this alone is enough to let me continue working inside the same space that nearly did me in just a few weeks prior.
I purchased two large 24″ high powered drum fans that can move on their highest setting 8,540 CFM. Anytime I’m inside the house working at least one of these in pointed directly at me. If I move to new location, so does the fan. If I’m upstairs I’ll usually place one at the bottom of the stairs pointing up to force some of the cooler air on the first floor up to the second.
The primary way our bodies cool themselves is through sweating. But sweating alone doesn’t help if it can’t evaporate. It’s the evaporation of sweat that cools the body and that is precisely what WASN’T happening to me that day. I knew this when I saw the sweat beading on my arms but what I didn’t know was just how fast I would overheat.
By simply placing a high powered fan in front of me wherever I’m working I’ve been able to continue on in relative comfort under the following conditions
These conditions result in heat indices 117°, 111°, 103° and 110° and wet bulb temps of 84°, 83.5°, 82°, and 82.1° respectively. Not exactly room temp but well within the range of what the human body can tolerate.
The human body: A robust cooling machine
If you’ve ever spent time in a desert environment then you’re well aware of how much better we tolerate “dry heat” even when the air temps get over 110°.
In these conditions we barely realize we’re sweating because the sweat evaporates so quickly, which keeps us feeling cooler despite what the thermometer says.
When I was laying asphalt shingles on our roof last summer I wondered why I could tolerate the extreme heat with relative ease when the temps on the roof were consistently over 110° and the relative humidity was high. The answer again lies in the microclimate.
Though the air above me may have had humidity levels over 50% the air near the roof and around my body was much, much drier, sometimes getting as low as 11% RH!
So just for fun I placed my temperature gauge in a hot sunny spot that would be similar to those working conditions. Take a look…
115° is hot no matter how you slice it but with a RH of 32% we’re looking at a corresponding heat index of 138° and a wet bulb temperature of 88°. Oppressively hot but manageable especially when you consider there’s almost always a nice steady breeze outside. Drop the RH down to the lowest I’ve seen on the jobsite (11%) and those values change to a heat index of 111° and a wet bulb temperature of 73°!
How’s Fonzie? Cool. Be like Fonzie.
I have two primary reasons for sharing all this information.
- Our summers are getting hotter.
- The onset of serious heat illness can happen very fast.
Reason one isn’t speculative. It’s true our summers are getting hotter. I gathered average temperature data for the month of July from the Coastal Carolina Regional Airport weather station (station ID KNCNEWBE18 for the weather nerds) between 1973 and 2022. Here’s what I found.
Here’s a PDF version too. Monthly Average Temperature for July in New Bern, NC
Regardless of whether you believe this is a natural phenomenon or caused by humans this data is clear. July’s in Pamlico County are getting hotter. And after my highly unpleasant experience I’m now acutely aware of how temperature, humidity, and wind impact how we feel and how are bodies respond when subjected to these conditions. On a 98° day a 30% increase in humidity results in conditions going from uncomfortable to nearly unmanageable, even for someone like me, young, athletic, and well adapted to hot weather.
So let’s say you’re out fishing and it’s full sun, hot, humid and breezy. These conditions may be unpleasant but probably won’t be life threatening. Anyone who’s spent time on the water around here knows that sometimes the wind just dies and the water gets slick as glass. Those unpleasant conditions just turned potentially fatal so it’s time to get that boat moving and generate your own wind!
If you’d like to learn more here are some helpful links I’ve found.