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Pondering Heat Stress and Dosimetry

Stay hydrated, get some shade, and take breaks.

The original dosimeter was made to detect radiation exposure. The original types, disposable, worked by making it apparent how much chemical change had resulted from ionization. Modern radiation dosimetry uses electronic sensors to achieve the same purpose, but are more accurate and reusable. (See OSHA: “Ionizing Radiation”: Dosimeters.)

There are also dosimeters for noise. They detect how much loud noise a worker is subjected to over time, in order to help protect their hearing. (See OSHA: “Occupational Noise Exposure”.)

And there is dermal dosimetry, which isn’t broadly developed, but is meant to measure how much of some environmental contaminant or toxin gets deposited on a worker’s skin. (See OSHA: “Dermal Exposure”.)

But I haven’t found much about heat dosimetry. (See OSHA: “Heat Illness Prevention” for general information about occupational heat stress.)

The labor problem of extreme heat may require the creation of a new type of dosimeter. This might be called thermal dosimetry, but that already refers to quantifying how much heat a medical patient receives in therapeutic hyperthermia—the use of heat to treat cancers.

Heat dosimetry would need to monitor a person’s time in environments that harm their body’s ability to regulate temperature. It’s a complex problem, which has been avoided in favor of self-monitoring and following general guidelines (access to shade, water, and breaks; monitoring environmental conditions generally, including sunlight and the heat indexed temperature).

It is somewhat complicated by the concept of acclimatization. People who are exposed to hot environments see their bodies adapt to be better suited to work in those environments. A gradual increase in exposure over a week or two makes the body better at sweating and maintaining body temperature in hot environments. (See CDC: NIOSH: “Heat Stress Acclimatization”.)

Would a theoretical heat dosimeter need to be calibrated or toggled for acclimatization? Only to a point. There are limits to how well the body can adapt to extreme heat and humidity, and so at levels beyond those, measuring strict exposure time would be enough.

Heat is a combination of several factors. Air temperature is the most obvious, but sun exposure and humidity are very important as well. There is also the surroundings, what the person wears, general fitness, and acclimatization. Finally, the type of activity the person engages in has a major effect in how rapidly they heat up.

If a heat dosimeter existed, it would need at least three components. One would monitor sunlight, another ambient temperature, and the third would measure humidity. Some reference values would be needed, but calculating the heat index with an adjustment for sun exposure would probably add up to a basic dose-check that could be used.

Unlike other exposure dosimeters, the big difference with heat is rapid recovery time—if the person has not been overexposed. While radiation, noise, and toxins provoke absolutely cumulative harms, heat exposure (up to a limit) can be tolerated with rest and removal from bad conditions. That’s an argument both in favor and against using dosimetry: it’s a recoverable condition, and regular breaks with relief from the heat are sufficient protection, but if only vitals are monitored, waiting for warning signs may be harmful.

On the other hand, measuring symptoms might work better than the traditional dosimetry approach. Monitoring the heat stress symptoms of the person may prove a better fit than trying to treat the problem like typical exposure dosimetry. That would include heart rate, body temperature, and hydration level.

Measuring acclimatization is important as well, and could probably be derived from the other measures. A person’s level of acclimatization can vary from day to day, depending on other stresses they may be under (including how much sleep they’ve had, dietary fluctuations), so acclimatization shouldn’t be treated as a binary.

Better heat-monitoring tools are definitely needed. Whether it’s practical or desirable to monitor exposure to environmental heat remains to be seen. Monitoring vitals directly, rather than exposure, has the benefit of alerting to other conditions and issues. Having regular breaks and access to adequate shade and cold water are enough to prevent most heat issues up to a point. Beyond that point, measuring heat doses may be important.

There are other alternatives to working in hot environments. Night work or temporarily and partially conditioned environments may be possible, but come with their own challenges. Night shifts cause sleep-related stresses and has some extra costs associated with it. Partial conditioning of a work environment requires extra labor and costs. How those costs stack up against working with heat isn’t clear.

For example, installing fixed poles for stretching tarps or canopies over a field to provide shade during fieldwork might be a practical mitigator for farms. Roadwork can benefit from night shifts, as it reduces traffic woes as well.

All that being said, it’s likely some companies have or will explore heat dosimetry. And it’s likely that at least some workers would benefit from it, even in the presence of direct monitoring of their vital signs and health. It will be interesting to see what the devices look like and how they operate.

It’s sure that the world is getting hotter from climate change, and we have to keep looking for ways to adapt.

Earth Day 2022

Another year in the books for the planet we all call home.

Please register to vote ( Please vote for candidates who will fight carbon pollution.

Month after month, year after year, we read about the climate crisis. The greenhouse effect was taught to me in school so long ago I barely remember the teachers’ names. And every year more carbon goes up, while many politicians still do not take the problem seriously.

Even as we face catastrophe, we learn the fascinating bits: how tree rings can tell us wet and dry years, or how layers of sediment in the oceans hold tiny shells that confess the atmosphere of their day, as do bubbles trapped in polar ice. (See Wikipedia: “Paleoclimatology”: Proxies for climate.) And it feels like sitting in a doctor’s office, being told of the scans and chemistries used to diagnose us, the doctor waving a slide rule as they tell us our odds of survival from a cancer or a heart attack unless we make a change.

We learn when distant cities will be underwater. How they will be flooded, first during storms, then tides. After that it won’t be flooding, it will have become part of the sea. There are maps showing the water moving in, from a centimeter every few years to a centimeter every year and beyond, if the carbon keeps flowing. The waters will skip the hills and makes them islands, for awhile anyway. If the waters keep going up, the new islands will be drowned. We see an artist’s rendering of what a mall looks like under ten feet of water.

The other disasters: major hurricanes, tornadoes, wildfires, the arctic vortex, droughts and floods. The own-goals: deforestation, methane leaks. And all the tips for reducing our carbon footprints. Less meat, reusable bags, changing lightbulbs, recycle, buy used. The media talks them up and then moves on to the latest politics, celebrity. We forget long enough to feel better, partying between hangovers.

The people making decisions aren’t worried, because they’re not paid to cut carbon. They’re paid to make sales. There are few jobs on the planet where the compensation goes up if the carbon goes down. They are renewable electricity generators, mostly. But the world has not put a price on carbon pollution. If it did, most everyone would earn more by cutting carbon, and the crisis would end. That’s the theory.

For those selling carbon offsets to wealthy people seeking to allay their guilt, there’s no extra money for lower carbon. Car makers don’t get a better price for making a more efficient car (though in some markets their days to sell carbon-powered vehicles are numbered). Oil drillers don’t have to pay for venting methane, as farmers don’t pay more for wasting water.

On Earth Day 2022, the situation looks the same as it has for decades. There are some modest efforts, far short of what’s needed. At the rate we are going, we will reach carbon neutrality later than needed, but we will get there. Not so optimistic, but not so pessimistic. We’re betting that knock-ons won’t turn out worse, that there’s no domino effect that will push us over a cliff.

It all feels like a missed opportunity, a lucrative one that the business community and the politicians were too dumb to take up. One that many of them agitate against out of some bizarre obligation to a sick system. There are many solutions that all miss the mark in one key area: the votes needed to pass anything.

Please register to vote ( Please vote for candidates who will fight carbon pollution.

The 2020 Climate Forums, Part 1

Some thoughts about the candidates’ answers at the first presidential climate forum.

Seven hours (minus commercial time) of candidate town halls on climate change.

What I wanted to see was realism, ideas, passion, and purpose on the issues of the climate. I saw a lot of that from almost all the candidates. Plans are something we need to see move through congress, and just because a candidate has a good plan doesn’t mean that happens. But, taken as a starting point, they are still useful and the candidates did a lot to discuss where they’re coming from.

Here’s a ranking of how I saw the candidates who participated. The ranking is in terms of the ideas they brought that differed from the pack, positive or negative, but not as an overall view of their plans. In general, all of their plans are good, particularly compared to inaction, and we need to act. The = # preceding a name means a tie.

  1. Booker
  2. = 1 Warren
  3. Yang
  4. Buttigieg
  5. = 4 O’Rourke
  6. Castro
  7. = 6 Harris
  8. = 6 Sanders
  9. Biden
  10. = 9 Klobuchar

I appreciated Booker and Yang speaking about the role of nuclear power. It’s not a perfect technology, and we should handle the waste responsibly by having a permanent repository, whether that’s Yucca Mountain or somewhere else. But it is carbon-neutral, and it cannot be ignored in our immediate and pressing need to deal with the problem of putting out too much carbon. Those who spoke against it, or who seemed to suggest that a permanent repository is a non-starter seem to deny the fact we already have a wealth of radioactive waste to store, and that even if we phased out all nuclear yesterday, we would still have the responsibility to handle that waste. They lost a point, accordingly.

Booker also spoke credibly on a number of other initiatives including farming, reforestation, and his record as mayor of Newark, New Jersey.

Warren spoke out on the need to do carbon-trade balancing—accounting for carbon in imports and exports, which is important. But she lost half a point for suggesting that all American-invented technologies related to climate would be exclusively manufactured in the USA. If we should eat local, we should also manufacture local, or at least leave the door open to it. (This will happen eventually as automation and fabrication technologies shift, but in the meantime we need to cut carbon more than we need trade protection. Licensing patents and technologies would allow us to spend the fees on other means to create jobs.)

Yang got a half-point for kind-of-implying the need for a treaty on geoengineering, which is something that is necessary and would include the fact that climate change and carbon pollution are already a form of geoengineering, as unintentional as it may be.

Buttigieg, in a question about his use of private flights in campaigning, spoke about the need for ground transportation including trains. Rail is important, so he got a point for that. The fact is that even the airlines should want us to build out rail, so they can save money on vouchers and have improved throughput by having a fully functioning, diverse transportation system. Everyone who complains about leg room or baggage fees should be in favor of rail.

O’Rourke was the only one who favored cap and trade over a direct carbon tax. There are arguments both ways, and either is useful, but I think there are some market effects possible with cap and trade that can be missed with direct taxes. On the other hand, there are hybrid approaches possible. The main downside of the tax approach seems to be that companies will seek to conglomerate on the basis of the tax rather than any inherent economic need, which can worsen an existing and awful feature of our corporate tax code. In any case, point for not bandwagoning on the tax.

Castro lost a point for suggesting that flood insurance should be subsidized in a way that suggested moral hazard. We can’t do that. We just can’t. There are other moves to make for folks who live in places that are no longer viable, but embracing it is simply folly.

Harris also spoke against nuclear power and waste. She did highlight some of her achievements as a district attorney and attorney general.

Sanders was among the candidates who stated unequivocally that some houses shouldn’t be rebuilt, and we have to face that fact. It’s part of the larger issue around rural-vs-urban and balancing freedom and subsidy in ways that make sense, some of which are climate-related and others of which are just fundamental issues we’ve never really worked out as a nation. For example, in some places farmers commute to the farm, rather than living there. On the other hand he was one of the more expressedly opposed to nuclear power. Again, it has problems, but it’s just not reasonable to condemn it given the challenge.

Biden’s main problem is this fundraiser with a fossil-fuel-tied host. That and he didn’t really seem to have a lot to say on the issue beyond a kind of “trust me” outlook.

Klobuchar lost points for her stances on nuclear power and fracking. While natural gas is better than coal when responsibly extracted, it’s not great and there’s plenty of evidence that it’s not responsibly extracted in too many cases. If the industry wants to be a bridge, it needs to show itself to be a safe one, not a rickety one. She did a good job talking about the opportunities with farms, as did several other candidates.

The climate is a big deal, and the Democratic candidates have set themselves apart from the Republicans by showing themselves to be thoughtful and studious on the issues. The challenge will come in implementing any of their plans, should a Democrat be inaugurated in 2021. But that’s always been a challenge, so long as Republicans have denied reality. It’s hard to move a couch when the other person carrying it doesn’t believe in the stairs.

In general, the 2020 Democratic candidates form a healthy slate. Most of the candidates are worth considering, and it’s hard to pick a favorite out of the pack. We will see how the debate goes this Thursday, and one hopes a few of the climate issues (maybe nuclear power, for example) can be brought up to help the candidates further explain how they approach the issue.

As to plans, they will be changed to become law. And they will be changed after they are law. Some changes good, others bad. There will be mistakes and unexpected wins, both. But we have to act on it. The Republicans fail to even propose plans on many of the pressing issues of the day, where for every single one there will be at least a few Democratic proposals.

That failure is a fundamental problem for our nation. The Republicans that cannot plan cannot lead. And yet there they are, in the driver’s seat of our nation, pressing nobs, turning buttons, and doing a whole lot of damage and nothing particularly useful. It is a shame.