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The Thermapen Instant-Read Thermometer

The Thermapen Instant-Read Thermometer

The instant-read thermometer that tops all others.

Welcome to One Simply Terrific Thing, our ongoing series highlighting the small tools and kitchen goods that make life better!

At the top of my “how did I ever live without this?” list is one of those small, unassuming kitchen tools that makes you think Oh man, I love this thing every time you use it.

It’s an instant-read thermometer, but seriously the best one out there: the Thermapen by Thermoworks.

When you need the internal temperature of something you’re cooking — how’s the chicken doing? Is the steak done? Is the chocolate up to temperature? — speed and accuracy is everything. The Mk4 Thermapen ($79 right now, usually $99!) gives you a temperature reading within 2 seconds. That means you can get that roast chicken back in the oven pronto before it cools down any more!

Other things I love about the Thermapen:

  • There’s no fidgeting with an “on” button and waiting for it to be ready; just open the probe and stick it in!
  • Hold it in any orientation and it will alter the display so the temp always reads right-side-up.
  • It has an automatic backlight so you can take temps in the dark (late-night BBQ, anyone?).
  • It’s always on when you’re using it, goes into sleep mode when you set it down, and automatically turns back on when you pick it up.
  • The battery (AAA) lasts forever. I don’t even think I’ve changed mine yet.
  • Did I mention it tells you the temperature almost instantly?

I keep ours in a drawer right next to the stove, since I am constantly reaching for it. I love how easy it is it to use, and that it takes the guesswork out of cooking meat.

Cheers to good tools!

-Cambria
“Product and Lifestyle Director


Review: Thermapen Instant-Read Thermometer for Festive Friday

The British have given us many things … tea and crumpets, double decker buses, The Beatles and the British Invasion, Hugh Laurie, Dame Judy Dench, Mini Coopers, fish and chips, American Idol, and Dancing with the Stars to name a few. There is one more that definitely belongs in this list … The Thermapen!

Made by hand in England, this is the Rolls Royce of all thermometers. I had wanted to try one for many, many years, but the cost always kept me from buying one. Instead I bought cheaper thermometers, one after the other, never satisfied with the quality or performance. If I add up the cost of all the thermometers I’ve bought over the years, I would have spent less if I had just bought a Thermapen in the first place.

A few months ago I was sent a Thermapen from ThermoWorks to review, and I instantly fell in love with it. When it comes to the equipment I use, I am extremely critical. But before I wrote a review, I wanted to put it through a series of tests.

Photo Credit: ThermoWorks.com

I used it with all kinds of meats and poultry – beef, lamb, pork, chicken, turkey and duck. I put it to use with a variety of cooking methods including, baking, roasting, grilling, frying, and poaching. I utilized it to measure the temperature of oil, caramel, cream, chocolate, and water. In each and every application is performed flawlessly.


Thermoworks Thermapen Mk4 Instant Read Thermometer Review – Buyers Guide

How to Use the Thermoworks Thermapen Mk4 Thermometer

Unlike some meat thermometers, the Thermapen Mk4 is simple to use. When you get it, you first have to insert the battery which is a 1.5-volt AAA battery. It will give you up to 3,000 hours of use without the backlight on which is good going especially as the battery is cheap. In addition, this type of battery is easier to source than the coin-type batteries which are often found in thermometers.

When you pick up the Thermapen Mk4, it will switch on and a large LCD display will come on. Immediately, it will start to measure the air temperature. If you are outdoors and want to measure the air temperature inside your grill to check that it’s correct for what you’re cooking, now is the time to do it. The thermometer works equally in the air and inside a piece of meat.

Once you have put your meat on the grill and have decided how long to cook it for, insert the probe into the meat at regular intervals, and you will get a reading in no time at all. You can measure different parts of the meat which is particularly important if you are cooking a large piece of meat. You will want all areas of the meat to be at the correct temperature. The center of the meat is going to take the longest to heat up, so you need to make sure that it is perfectly cooked. The probe is 4.3 inches long.

The temperature range of the Thermapen is -58F – 572F which means that it can measure the temperature of most foods. It will even be able to measure the temperature of a steak which has to be high in the middle. The thermometer is accurate within +/- 7F from -58F – 392F. With higher temperatures, it is accurate to 1.8F. It can read lower temperatures better than most other thermometers out there. Test it out on very cold water which is about to freeze.

It is easy to clean the probe when you have finished using it. All you have to do is wipe it down with a paper towel. It is waterproof to IP67 standards, but there’s no need to immerse it in water as only the probe needs to be washed. Remember that it isn’t dishwasher proof. However, it’s reassuring to know that if you forget and leave the thermometer outside and it rains, it won’t be ruined.

Alternative Instant-Read Thermometers

So, is there much competition when it comes to instant-read thermometers? Well, there are certainly a lot of others out there and we’ll take a look at a few of them here. Thermoworks sells another instant-read thermometer called the Thermopop, which is nearly as good as the Thermapen Mk4, but not quite. For a start, the Thermapen reads temperatures quicker than the Thermopop. While the Thermapen can read temperatures within 2 – 3 seconds, the Thermopop reads temperatures in around 4 seconds. In addition, the Thermapen is more durable than the Thermopop. The casing on the Thermapen is thicker than that on the Thermopop and is more waterproof. The Thermapen is often used in professional kitchens because of its speed and accuracy, while the Thermopop is used more at home. However, the Thermopop is a good deal cheaper than the Thermapen. It is around 1/3 rd cheaper which is a big saving if you are on a budget. However, if you do have the money to spend on a thermometer, the Thermapen is a better bet.

Thermoworks still manufacture their Classic Themapen, but it doesn’t have as many features. For a start, it doesn’t auto-rotate nor does it sense sleep and awake mode. It isn’t waterproof and the battery lasts for only half of the battery life of the Thermapen. However, like the Thermopop, it is cheaper than the Thermapen.

The Thermapro TP19 is the only instant-read thermometer that can read temperatures quicker than the Thermapen. The average speed of the Thermapro TP19 is 2.7 seconds compared to 3.6 seconds in the Thermapen. The average speed in ice is 3 seconds in the Thermapro and 3.3 seconds in the Thermapen. In boiling temperatures, the average speed of the Thermapro is 2.7 seconds, while in the Thermapen it is 3.8 seconds. The Thermapro TP19 is one of the few instant-read thermometers out there that surpasses the Thermapen on most counts.

Another thermometer to look at is the Lavatools Javelin PRO. The Thermoworks Thermapen Mk4 has a larger temperature range on both high and low temperatures. The Javelin PRO’s temperature range is -40F – 475F. When it comes to comparing the temperature speed, the Thermapen is faster by 1.1 seconds on both high and low temperatures.

The Taylor – 9867B is extremely like the Thermapen so there is no need to distinguish between them.

Should You Buy the Thermapen Mk4?

If you take grilling and smoking seriously and often, this thermometer is ideal for you. It won’t take you a long time before you wonder how you got on with your last and inferior instant-read thermometer. The Thermoworks Thermapen Mk4 reads the temperature so quickly, autorotates so you can see the temperature from every angle and lights up in low light automatically. You don’t even need to change the battery for at least 2 years. In addition, you can use the thermometer anywhere. There’s nothing wrong with using it on your stove when you are cooking in the winter. The price might be steep, but it is well worth the extra cost.


Pan-Roasting and Grilling

For relatively smaller cuts of meat like chicken breasts, pork chops, salmon fillets, and steaks, an instant-read thermometer is also indispensable. That's because common tricks like pressing on your steak with a finger to assess its internal temperature are notoriously unreliable, while overcooking your food to ensure it's cooked to a safe internal temperature isn't exactly an appealing alternative. Again, I'm speaking from experience here: I used to grill my chicken breasts until they were dry as chalk on the inside (lol, who am I kidding, I live in NYC so ergo I don't own a grill—I was pan-roasting them to a chalky doneness). I used to think pork chops required a pan sauce, since there was no way anyone would want to eat a bundle of pork fibers plain.

Short of going the sous vide route, using an instant-read thermometer is the only way you're ever going to safely eat a moist and tender chicken breast, or enjoy steaks cooked to your preferred doneness every single time, or bite into a perfectly cooked medium-rare pork chop.


Why You Need an Instant-Read Thermometer: The Thermapen, Thermopop, and Smoke

Let’s talk about measuring the temperature of what you’re cooking as well as what you’re cooking in, the type of tools you can use, and how to know what you’re using is accurate. The single most important tool a BBQer or griller can own is a thermometer. This is a device used to measure the internal temperature of whatever it is you’re cooking or what you’re cooking it in. Thermometers come in many styles: single probe and multiple probe versions, digital and dial types. The main purpose of s single probe thermometer is to check the temperature of what you’re cooking. Multi-probe thermometers are great for measuring not only what you’re cooking but the temperature of your grill or smoker (cooker) as well.

I could spend a long time talking about thermometers, the various types, how each type works, and the pros and cons of each. Instead, let me explain a few basic concepts when it comes to using them and how to ensure they’re accurate.

Today I want to take a look at two general types of Thermometers, single probe and multi-probe. Let’s start with the single probe thermometers, often referred to as instant-read thermometers. If you can only own one thermometer, it needs to be a single probe. It’s the only way you can really know when your meat is properly cooked.

Using an instant-read thermometer is pretty straightforward. You want to check the temperature in the coolest part of the meat. In general, that tends to be the thickest part of the meat. Insert the thermometer probe into that part of the meat and wait until the reading on your thermometer stops rising. This will take anywhere from 2-14 seconds, depending on the thermometer you have. It’s really just that simple.

It really is that simple with a Thermapen.

My suggestion is to get the best you can afford. It’s no secret that here at GrillGirl.com we are big fans of the Thermapen , and with good reason. Yes, at first glance they may seem expensive, but in all honesty, it’s a really great value. It’s accurate, extremely fast, last for years, has a great warranty, and is repairable.

Another great option is the Thermoworks Thermopop . The Thermopop is a great little instant-read with a lot of the same features as the Thermopen for around $29.00. Thermoworks also has instant-read thermometers for as little as $19.00. If you just can’t swing a thermometer from ThermoWorks, head to Wal-Mart and get a $10.00 something. Just get a thermometer! Every cook needs at least one!

By the way, if you sign up for the Thermoworks newsletter , you will be notified of sales and be entered to win a Thermapen, which they give away each month. (At least they do at the time of this writing.)

Multi-probe thermometers

These type thermometers typically come with two or more probes on cables leading back to the thermometer’s main unit, One probe attached to the cooking grate to measure the cooker temp and the others inserted into the meat. A great example of these types of thermometers is the Thermoworks Smoke .

A Thermoworks Smoke multi-probe thermometer.

Go out and get yourself a thermometer. A Thermopen, a Thermopop, or something else. Just go get one and start using it today.

Until next time, Happy Grilling!
Jon

GrillGirl Contributor, Jon Solberg.

Jon Solberg, Expert Outdoor Cook who Makes His Own Charcoal!

E njoys long walks on the beach and good comedy….. Just kidding! A student of all things outdoor cooking, both low and slow or hot and fast. Charcoal, wood or gas it doesn’t matter. Not a big believer in the dogma of outdoor cooking. Continually looking for different ways. Loves to restore grills and smokers of all kinds. Born and raised in Mid-Michigan and understands there’s no offseason in live fire cooking.

**Affiliate links have been used in this post, which means I could make a small commission if any products are purchased. I only recommend products that I personally use and endorse. (Robyn)


Super-Fast Thermapen® Mk4

Fast and accurate with a huge range, this is our go-to thermometer for ensuring success when bread baking in the King Arthur test kitchen, helping us know exactly when our bread is done -- no more doughy centers or sunken quick breads. This model uses advanced technology to make it even more user-friendly: The display rotates when you move it, so you're always reading upright, and an automatic backlight features adjust to dark and light environments for easy reading. A sleep mode helps preserve battery, turning off the Thermapen automatically when not in use. When the Thermapen detects motion, sleep mode turns off automatically and powers back on. We also love using it for everything from baking bread to frying, candy-making, and even grilling.

What you get
  • Accuracy is ±0.7°F from -58 to 392°F and ±1.8°F from 392°F to 572°F
  • Display scale can be switched from °F to °C
  • Auto-off can be disabled for continuous readings
  • Stainless steel probe folds back to store locked in place
  • Battery operated (1.5 volt AAA battery included), with 3,000-hour battery life
  • Fully sealed to be waterproof
  • Total range: -58 to 572°F
  • Readings in just 2-3 seconds
  • Needle-thin tip activated with just 1/8" inserted
  • Measures in .1°F increments
  • 2-year warranty
  • Made in England
More information

King Arthur Baking is an authorized dealer for ThermoWorks products. Not eligible for discount promotions.


This Thermometer Is Way Too Sensitive (Or Maybe Just Enough)

A non-digital, dial-style thermometer probe contains a spring in the probe with two metals that lengthen and shortens based on the heat (more about the trouble with that in a second). A Thermapen, on the other hand, operates using a two-wired probe, which reads the difference in voltage between the wires. This makes them more sensitive to temperature fluctuations, and that makes the digital readouts more accurate—and faster (is 3 seconds good enough for you?).

A dial thermometer's probe can often be up to 2 1/2 inches long, and in order to get an accurate reading, most of the probe needs to be exposed to temperature you're measuring. That means when you insert one of these old-school thermometers into your pork roast, you're getting a rough average of temperatures throughout the meat, rather than an accurate reading of the temperature at the very middle of the roast. The Thermapen's probe obtains all of the data in the tiny tip of the probe, which means you can tell instantly if your pork roast is still bright pink in the center.


Classic Super-Fast ® Thermapen ®

Classic Thermapen changed the world of cooking with its folding probe, huge display, and unmatched speed and accuracy. Classic Thermapen has the same Type K thermocouple sensor as the Thermapen Mk4 but without all the bells and whistles.

Super-Fast® and Accurate: 2-3 second readings with ±0.7°F accuracy
With full readings in just 2-3 seconds, Classic Thermapen is the world’s best in speed and accuracy.

Long Battery Life: 1500 hours of battery life
Always there when you need a temp check.

Auto on/off: No unnecessary buttons
We built in the auto on and off feature to eliminate buttons that trap food and bacteria in crevices.

NIST-Traceable Calibration Certificate
We are the only thermal instrument company who houses its own calibration lab.

  • High accuracy to ±0.7°F (±0.4°C)
  • Water-resistant design
  • Includes Biomaster silver ion technology to reduce microbial growth
  • °F to °C reconfigurable

Classic Super-Fast Thermapen is a professional tool (originally designed for commercial kitchens, labs and manufacturing plants) that has become the top consumer cooking thermometer for home use. Its popularity among celebrity chefs, cooking magazines, top foodies, bloggers and competition BBQ teams has made the Thermapen into an essential tool in the best-equipped home kitchens and backyard BBQ rigs.

Made by Hand in England, the Thermapen is faster and more accurate than any other cooking thermometer on the market. Competitors have tried to copy the Thermapen with mass-produced products made in China and have flooded the housewares market with slower, less-accurate knock-offs. However, when compared to true competing commercial thermocouple thermometers, the Thermapen is not only faster and more accurate, it's also less expensive!

The Thermapen's speed and accuracy will reveal more about food and cooking techniques than you ever imagined. You'll learn that temperatures are always changing a roast is never the same temperature throughout while cooking. If you want to know what's really going on, get a Thermapen.

If you want to experience speed and precision (traceable to National Standards) and you're on a quest for culinary perfection, you will want a Thermapen. Add up the expense of wasted meats alone and you'll justify the cost of this professional tool.

A Thermapen can be used for virtually anything that needs to be cooked or chilled. Use it on meats, fish, casseroles, re-heated foods, breads, cakes, deep frying and candy. You don't have to have a Thermapen to be a great cook however, more than one celebrity chef and several food writers have testified that a Thermapen will make you a better cook. AND, you can choose your own color! Order one today.

From the Blog

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The Thermapen Is the Last Cooking Thermometer You'll Ever Need

"It takes readings in less than three seconds, is accurate to less than a degree, and is designed to last for ages. It really is the best cooking thermometer we’ve ever used, and it deserves a place in your kitchen."
Read the Review

A $99 Thermometer? Why the Thermapen Is Worth It

"There is one tool in the kitchen that I simply can’t do without. Now, I really don’t believe that you must buy a bunch of pricey tools in order to cook well, so recommending a [now $79] thermometer may seem out of touch. But honestly: this incredibly useful, incredibly fast and accurate thermometer is a game-changer. "
Read the Review

Alton Brown's GEAR for Your Kitchen

"The thermometer I use most is the Thermapen by ThermoWorks, and, no, I'm not paid to say that. This particular model edges out other (cheaper) digitals because it's got a long, rotating, orientable probe, a huge readout, and circuitry that updates its information faster than any other model. " (pg. 167)

Specifications
Range-58.0 to 572.0°F (-49.9 to 299.9°C)
Accuracy±0.7°F (±0.4°C) from -58 to 392°F (-49.9 to 199.9°C), ±1.8°F (±1.0°C) from 392 to 572°F (200 to 299.9°C)
Resolution1.0°F/°C full range (user reconfigurable to 0.1°F/°C)
Response Time Full reading in 2-3 seconds (0.4 seconds per time constant)*
Probe4.5 L inches, High Performance Type K Thermocouple
Display0.55 inches (14mm) LCD
Auto Shutoff10 Minutes (user reconfigurable to disable auto-off)
Operating Range-4 to 122°F (-20 to 50°C)
BatteryCR2032 (3V) lithium coin cell x 2, 1500 hours
Dimensions1.85 H x 6.1 W x 0.75 D inches (47 H x 153 W x 19 D mm)
Weight0.25 lbs (97g)
CertificateIncludes NIST-Traceable calibration certificate

* Response time defined as five time constants for 99.3% of actual temperature.

Visit our Help Center For more information and troubleshooting tips.

Downloads

Complimentary Guidebook with every Thermapen Purchase

Order a Thermapen today and we'll throw in a copy of our new 20 page guidebook: "Using Your Thermapen: A Guide to Better Food Through the Proper Use and Care of Your Splash-Proof Thermapen" at no extra charge. The guide features basic cooking temperature principles, step-by-step instructions for customizing and cleaning your Thermapen, special considerations for getting just the right doneness with meat, poultry and fish, QuickTips, Frequently Asked Questions, diagrams, and more. Plus, there's a handy chart of food safety and chef-recommended temperatures on the back!

If you own a Thermapen and don't have a guidebook but would like one, Request a guidebook to have one mailed to you.

Available in Multiple Colors

Originally, we manufactured the Thermapen in gray only. Later we added all the food-safety color-coding versions. Many people in the food industry use color coding to prevent cross contamination by dedicating tools to specific food products. That way, a knife, cutting board or thermometer that is used for say, raw poultry, won't end up contaminating fresh vegetables like salad greens.

That was the reason we did multiple colors for the Thermapen. Of course most people buy a color variety simply according to personal preference. Even in commercial applications it seems most people buy colors so they can quickly tell who belongs to which Thermapen (blue is Fred's, yellow is Cathy's, etc…)

In 2006 we added black and orange which weren't even on the color coding system. If you have a color preference that we don't make yet, email us and we'll keep track of your vote.

Standard Color Code:
Red = raw meat, raw beef and pork.
Blue = raw seafood
Yellow = raw poultry
Green = produce
White = dairy or bakery items

What is Biomaster?

Biomaster is a silver-based antimicrobial additive that is molded directly into the plastic housing that becomes an integral part of the product to prevent bacteria growth on its surface. The controlled release of the active ingredient provides maximum antimicrobial protection for the life of the product. When bacteria come into contact with a Biomaster protected surface, the silver ions prevent them from growing, producing energy or replicating, therefore they die, inhibiting degradation, discoloration or odors. Biomaster is an additional line of defense between cleanings.* *Biomaster does not protect the user from disease causing organisms and is not a substitute for good hygiene and/or cleaning.

Classic Thermapen FAQ

1. Where can I buy the Thermapen?
You can buy it right here online. There are only a few authorized dealers, (watch out for counterfeit Thermapen look-alikes). There are a few retail outlets in the U.S. and Canada that stock the Thermapen.

2. Why don't more retail outlets carry it?
Most retailers want to more than double their money. The big name chains want the most. If a product costs them $4, they want to charge you $10. The Thermapen is already priced at "Trade Pricing". Meaning, this is the price we sell it to commercial food service users and health departments. And, we offer it to the general public at the same price. Big retail chains would have to charge you much, much more and they'd still be mad that we would take your order at a lower price. The retailers that do carry the Thermapen are not making their normal mark-up so thank them if you buy there!

3. Where can I buy replacement batteries?
The Classic Super-Fast Thermapen uses two coin cell batteries, CR2032, which are commonly found at Wal-Mart, Target, and other stores. You can also order spare batteries from us.

4. How long should the battery last?
The Classic Super-Fast Thermapen batteries are rated for 1,500 hours of use (was 100 hours). In the battery compartment you can enable and disable the auto-off feature. The auto-off feature will extend the life of the batteries. See owner's manual for details.

5. Will the Thermapen tell me when my meat is done?
Not exactly. Instead it (very quickly) tells you the actual temperature and you decide if that is "done". We can give you the USDA guidelines for food safety but you should consult your favorite cookbooks, TV shows and recipes for advice not only on safe temperatures but the best cooking temperatures for flavor and texture. Also remember that individual preference is very important.

6. Other digital cooking thermometers are cheaper. Why pay more for a Thermapen?
In use there's a big difference. Don't take our word for it. Check our Reviews page to read the many reasons written by others. Cheaper thermometers are limited by the technology that they use. These can be mass produced for just a few dollars. On the other hand, the Thermapen is hand-assembled and hand-tested and uses a professional thermocouple circuit design. This design costs more to make than the cheap thermometers.

7. Why is the Thermapen so much faster than other cooking thermometers?
The main reason is the professional thermocouple technology that we use instead of mass-produced thermistor technology. Thermocouples are recommended by the USDA for measurement of cooked meat products and thin portions. Go here to see what a thermocouple means in performance vs. a thermistor. We also use a reduced-diameter needle tip on the probe. Comparable professional meters cost $140 to $300 for the electronics and a similar probe! Some improvements were made in the sensor manufacturing process and the probe assembly in the new Splash-Proof Thermapen to make it just slightly faster than the original Super-Fast™ Thermapen.


What We Loved

There’s so much to love about the Thermapen Mk4. The AAA batteries used are easier to locate than the coin type battery used in the classic Thermapen. The fast and accurate read time of 2-3 seconds is amazing. The easy to read auto rotating display with intelligent backlight is a must have feature.

The waterproof feature is certainly a plus, but remember the unit is not dishwasher safe. The 2-year warranty on the body and the 6-month warranty on the probe is hard to beat. ThermoWorks has one of the best service departments in the business so there’s a good chance even if your Themapen Mk4 is out of warranty, it is repairable at a minimal cost.


Bonus Content

How Instant Read Thermometers Work

In general thermometers take some material that changes when it’s heated, then measure that change with some other measuring device. For example, mercury expands when the temperature goes up. Your classic mercury thermometer has a precise tube where the mercury can expand that’s marked with a specialized ruler. As the mercury expands, we read the temperature off the ruler.

In the case of digital thermometers, we’re measuring the changes to different electrical properties as temperature changes. For thermistors and resistance temperature detectors, the property is electrical resistance. For thermocouples, the property is the voltage created by the junction of two different metals. A lot of people have loud opinions about what technology does better for accuracy or better for speed. It’s easy to go down a rabbit hole here, and with the time I’ve spent in there, you can all but call me Alice. The big takeaway, in my opinion, is that the choice of sensor matters a lot less than how the engineers design the thermometer around it. Don’t get hung up on thermistors vs. thermocouples unless you have extremely specific needs. Focus on the end results.

Calibrating a Thermometer

If you’re concerned about the accuracy of your thermometer, you can test its performance in an ice-water bath. Your better class of thermometer can be recalibrated, maybe by you or maybe by the manufacturer. A cheapy might just need to hit the garbage.

This is more complicated than just fixing yourself a cold drink. You need to make a mix of ice and water that’s exactly 32°, and that takes some work. As you can see in our photos, our uncareful bath is 34°. To do it right, fill an insulated cup most of the way full with crushed ice. Fill most of the way with water and let sit for a minute to let the temperature equalize. Insert your thermometer and stir with the probe. The number on the screen should be 32° ± the manufacturer’s published tolerance ± how imperfect your ice bath is.

You can also check the result against another trusted thermometer. Get the sensors as close together as possible in the ice bath without touching the probes together. The numbers should be equal, ± the manufacturer’s tolerance for the test thermometer ± the manufacturer’s tolerance for the trusted thermometer. As you might guess from reading this, that won’t tell you much unless you have a very accurate trusted thermometer. Better to learn how to make a really good ice bath.

Boiling water is more suspect than freezing water. Where freezing temperature only changes in situations where you would die, boiling temperature changes all the time. It drops a degree for every five hundred feet of elevation gained, and moves with the local barometric pressure. There are online calculators where you can punch in your data and get an estimate of local boiling temperature, but that’s just another error term for the pile.