The Hidden Dangers of Heat for Live Entertainers, Cosplayers, Furry's, and Santa
Heat is more dangerous than most of us realize, especially for those spending long hours in costumes. Globally, heat causes more deaths each year than hurricanes, tornadoes, and floods combined, yet it's not treated as the deadly threat it is.
Despite its severe impact, no heat event has ever been classified as a natural disaster by the U.S. Federal Emergency Management Agency (FEMA), leading many to underestimate its risks.
One critical factor to remember is the heat index, which combines air temperature and humidity to reflect how hot it feels to the human body. While a thermometer might say it's 85°F (29°C), the heat index can make it feel much hotter – sometimes dangerously.
Did you know humans have a heat stress threshold of 85°F (29°C)? Once the heat index surpasses this, our bodies struggle to dissipate heat and cool us down, making simple tasks exhausting. When the heat index hits 95°F (35°C), our work output drops by 45%.
Heat stress doesn't just make you sweat – it forces your heart to work overtime to regulate your body temperature, which can have serious long-term consequences. Repeated exposure to heat, especially in costumes or heavy gear, puts immense strain on the cardiovascular system. Over time, this can exacerbate existing heart conditions and lead to chronic health issues. Studies show that repeated heat stress can cause or accelerate heart problems, even for people without preexisting conditions.
The result? Long-term damage that builds quietly and often goes unnoticed until it's too late.
The effects of heat stress extend beyond the heart. Prolonged exposure to high temperatures can damage kidneys, impair cognitive function, and lead to severe dehydration. Heat can cause persistent fatigue and, in extreme cases, can be fatal. The heart, however, remains the primary concern—heat forces it to pump harder and faster, increasing the risk of cardiac events.
According to the U.S. Centers for Disease Control (CDC), heat kills around 1,200 people each year in the U.S. alone, a number that's risen from 700 just a few years ago. However, experts believe the number is much higher, likely around 10,000 annually. Why the discrepancy? Death certificates rarely list heat as a cause of death.
When people die from complications exacerbated by heat – whether from heart failure, stroke, or even complications from conditions like Alzheimer's – heat is often not officially noted as the cause.
The link is clear: hot weather leads to more cardiac arrests, strokes, and diabetes complications. It aggravates neurodegenerative diseases and worsens the health of people with existing medical conditions. The consequences are severe, often deadly, and far-reaching. Understanding these risks is the first step toward protecting yourself, especially costuming in hot conditions.
Remember your last hot outdoor event this summer – maybe a day at an amusement park, an all-day family gathering, or camping. Perhaps it was something like the Renaissance Festivals, Shakespeare in the Park, theater on a stage, or a parade. It was fun in the sun, but the next day, you felt wiped out, fatigued, weak, and even nauseous. You might have thought you just "overdid it" or regretted that extra corn dog. While overexertion and that extra treat might have played a part, the real reason you felt unwell is likely the heat. Many people don't fully grasp how much heat can impact their bodies.
The human body is like a fine-tuned machine that needs to operate within a specific temperature range for optimal performance. It's a Goldilocks situation: not too hot or cold, but just right. When our core temperature gets out of the 92 ̊F to 104 ̊F (33°C to 40°C) range, it can lead to some scary and dangerous symptoms.
For example, hypothermia, or being too cold, starts when our core temperature drops to 92°F (33°C). At 80°F (27°C), our heart and lungs can no longer function. Conversely, hyperthermia, or heat stroke, begins when our core temperature hits 104°F (40°C). Our brain can shut down if it reaches 109°F (43°C).
Let's dive into a quick lesson on how our bodies handle heat. Our bodies use four main mechanisms to regulate temperature: convection, radiation, conduction, and evaporation.
First up is convection, which is the transfer of heat through air. For example, heat rises from the ground, and your body absorbs it, causing your core temperature to rise.
Next is radiation, the transfer of heat through space through invisible energy waves, like infrared light.
Think of the sun's heat. When you're in costume, your outfit absorbs this radiant heat, just like a dark T-shirt does on a sunny day.
This is especially noticeable during events like parades, Pennsic War, Colonial Williamsburg, or Renaissance Festivals.
Conduction is the transfer of heat through an object or between two objects in direct contact. For instance, heat from hot pavement is conducted to your body.
Remember, heat always moves from the hotter object to the cooler one.
Finally, evaporation is how sweat on your skin turns into vapor, helping to cool you down by carrying away excess heat. We rely heavily on this process to regulate our body temperatures.
Sweating alone doesn't cool you off – your sweat is the same temperature as your core, 98.6 ̊F (37 ̊C). Instead, it's the evaporation of sweat that cools your skin. Think of your skin as a radiator: hot blood moves to the surface, making you sweat. The wind then evaporates the sweat, cooling your skin and blood, which helps maintain a steady core temperature.
Imagine sitting on your porch on a partially sunny 70°F (21°C) day with a gentle breeze – it's relaxing. Now, picture sitting on the same porch on a 90°F (32°C) day with intense sun and a hot breeze–it's not comfortable at all. The difference is heat stress. Your core temperature and heart rate are rising. For every degree your internal temperature increases, your heart beats about 10 beats per minute faster, putting extra stress on your heart.
As your body overheats, it works harder to cool down by dilating blood vessels, which increases blood flow to the skin and makes you sweat. This can lead to breathlessness, especially for those with asthma or chronic obstructive pulmonary disease (COPD), and can also cause issues like low blood sugar for diabetics and dehydration, which might result in dizziness and fainting.
So, on that hot day, when you feel wiped out after being in the sun, it's because your body has worked hard to keep you cool even if you don't always "feel" the increase in heart rate or core temperature. This is how heat causes fatigue.
Recognizing signs of overheating, heat exhaustion, and heat stroke—such as heavy sweating, cold or clammy skin, a fast, weak pulse, nausea, muscle cramps, dizziness, headaches, or fainting—is crucial. However, these signs can be vague and quickly brushed off. Nausea? I shouldn't have eaten that corn dog. Dizziness? I was spinning fast when I was dancing. Headache? I didn't have my cup of coffee this morning.
Overheating can happen gradually or suddenly, and in severe cases, it can be fatal. Therefore, it's essential to address your core temperature rather than just the symptoms of overheating.
Our bodies generate heat as a by-product of energy production. When we're in costumes that trap this heat, it can create a high-humidity environment where sweat can't evaporate, making things worse. If your costume doesn't allow for sweat evaporation, it will make you hotter every time.
As sweat accumulates, humidity inside the costume quickly rises from 20% to 100%; at this point, evaporation stops entirely. The combination of heat and high humidity, activity, and heavy costumes, can create dangerous conditions, increasing the risk of heat-related illnesses for actors and performers. Even indoors, hot studio lights and poor ventilation can contribute to heat stress.
High-Risk Roles
Heat presents an even more significant challenge for those in high-risk roles, particularly actors and performers who wear heavy or non-breathable costumes, often for hours at a time.
Peter Mayhew, who portrayed Chewbacca in the Star Wars films, faced significant overheating issues while filming in his iconic Wookiee costume. The costume, made of yak hair and mohair attached to a knitted wool suit, was cumbersome and incredibly hot, especially during desert scenes in Return of the Jedi.
The production team had to take extra precautions, ensuring Mayhew stayed hydrated and cool between takes to prevent heat exhaustion.
Kenny Baker, who brought R2-D2 to life in the original Star Wars trilogy, also endured extreme heat. The small, enclosed space of the R2-D2 suit, coupled with the sweltering desert locations, created a virtual oven for Baker. He often felt faint and had to be removed from the suit to cool down, and the crew developed unique cooling methods to help him get through his scenes.
Michael Keaton had a similar experience while filming Batman Returns. The heavy rubber Batsuit, designed to look imposing on-screen, was nearly suffocating for Keaton, trapping heat and preventing ventilation.
His discomfort was so intense that the production team had to schedule frequent breaks and develop cooling techniques to keep him functional on set. Keaton has spoken in interviews about how grueling it was to perform under such conditions, with the risk of overheating a constant concern.
These challenges aren't limited to blockbuster film sets. Performers in theme parks, Renaissance festivals, and outdoor events, such as cosplayers and fursuiters, often wear full-body costumes that make it challenging to regulate their body temperature. Studies by the U.S. National Institute for Occupational Safety and Health (NIOSH) have highlighted the prevalence of heat stress among outdoor costumed performers, emphasizing the critical need for effective cooling measures. Reports from conventions and events frequently cite instances of heat exhaustion in performers, underscoring how serious the issue of heat stress truly is.
The dangers of heat stress are even more pronounced for costumed performers in high-risk roles. Remember the human heat stress threshold? When the heat index exceeds 85°F (35°C), work output can plummet by as much as 45%. This means that performers not only give 45% less to their performance but also put their health at serious risk.
The energy, focus, and physical ability needed to deliver a complete performance are severely compromised, turning what should be a creative expression into a potentially dangerous situation. At these temperatures, staying cool isn't just about comfort—it's essential for safety and well-being.
These photos from Midwest FurFest show Furries walking around the Dealer's Den. The maximum temperature in the thermal image above is 103.7°F (39.8°C), especially noticeable in the bright yellow and white areas like the head and armpits. Heatstroke starts at 104°F, so this furry is just a fraction away from serious heat issues and likely experiencing some heat exhaustion symptoms such as excessive sweating, headache, and dizziness. And remember, they're just walking around, not dancing or exerting themselves.
Now, check out this other furry in the Dealer's Den. The maximum temperature here is 105.3°F (40.7°C), well into heatstroke territory, which begins at 104°F. This furry is likely experiencing classic signs of heatstroke: hot, red, or dry skin, a rapid pulse, headache, confusion, nausea, and dizziness. Without immediate cooling relief, this situation can become life-threatening.
The image above shows the inside of a furry head after it's been removed—it's 92.4°F (33.5°C) inside! And that's after taking it off—imagine how much hotter it gets when it's back on. Combined with body heat and sweat, it pushes temperatures well into the 100°Fs (high 30°Cs).
You might wonder if this affects other types of costuming. Absolutely—it's not just Furries who face this issue! Take this historical costumer (right), for example. In an air-conditioned space during a photoshoot, she starts overheating at 101.2°F (38.5°C) without a cooling vest.
After putting on the cooling vest, her body temperature begins to drop almost immediately, showing just how crucial these cooling solutions are for anyone in elaborate costumes.
Let's dive into another key piece of the heat puzzle: Environmental Conditions. We've got temperature, humidity, direct sun, and air movement, but what about sneaky heat sources like hot lights or relentless sun?
And let's not forget the real kicker at conventions—the Masquerades and performing on stage.
Imagine a skier out in the snow, fully geared up in long johns, snow pants, a heavy coat, gloves, boots, and a helmet—now imagine them dancing away in that outfit with no chance of staying cool. That's what it's like for costumers and live performance actors trying to keep their core temperature down.
Think back to your last Masquerade or Renaissance Festival, when you wore your full costume and pushed yourself a bit too far. You probably felt warm and sweated buckets, and those last few minutes were a real struggle. The next day, I bet you were exhausted. You are experiencing heat stress, just like sitting on the porch in 90-degree weather—heat wears you out.
The good news? Many heat-related issues we've talked about are preventable. But some things, like health conditions and medication interactions, are not. As we age, our risk for heat-related issues increases. Got asthma, high blood pressure, or diabetes? These conditions can worsen in the heat. People with diabetes struggle with temperature and blood sugar regulation. Heart disease increases the risk of heart attacks, and asthma or COPD can make breathing more challenging. Even mental health can take a hit; there's evidence of higher rates of suicide, homicide, and violent crime on extremely hot days.
Also, remember that medication—allergy meds, antidepressants, beta blockers—can all have side effects that affect how the heat sensors in your brain handle heat. Please talk to your doctor about how your medications might interact with heat.
So, how hot is it? To find out, we need to look beyond just the ambient air temperature. Weather stations measure official daily temperatures in the shade, but direct sunlight can raise the actual temperature by as much as 15°F (8.3°C).
Some Weather Math
The heat might not be as extreme for low-humidity situations like indoor Masquerades or stage performances, but it's still significant. In a room with an ambient temperature of 70°F (21°C), adding lights and nerves (+15°F, +8.3°C), costume (+5°F, +2.8°C), and age, health, and medication (+5°F, +2.8°C) will quickly push temperatures to around 95°F (35°C)!
For a high-humidity outdoor event in the sun in Atlanta in July, the "Feels Like" temperature (Heat Index) is 101°F (38.3.°C). Factor in direct sun (+15°F, +2.8°C), costume (+5°F, +8.3°C), and age, health, and medication (+5°F, +8.3°C), and you're looking at a potential 126°F (52.2°C)! I know it sounds extreme, but hear me out.
Here's your heart temperature. Your heart is calculating this temperature while trying to cool your body.
• Low humidity situation: Feels like 70°F (21°C) but our heart is calculating it at 95 ̊F (35°C).
• High humidity situation: Feels like is 101 ̊F (38.3.°C) but our heart is calculating it at 126 ̊F (52.2.°C).
I know that 126 ̊F (52.2.°C) looks crazy...and it is. That is a recipe for Heat Stroke or death. No one should be performing in that kind of weather in a costume.
So, how can you help your body and heart stay cool? Let's explore some cooling options. Cooling vests come in various styles, each with its own set of benefits and drawbacks:
Gel Pack Cooling Vests
These vests use cooling sheets that need to be soaked and frozen. They're relatively inexpensive but can feel slimy and have limited longevity. They also tend to create condensation, which can dampen you and your costume.
Embedded Gel Cooling Vests
Lightweight and easy to use, these vests contain hydrogel crystals that activate when soaked in water. While they're among the lightest options, they typically last between 30 minutes to an hour and can be damp, which may not be ideal for prolonged use.
Ice Pack Cooling Vests
While heavier and bulkier, they are inexpensive, simple, and effective. These vests use frozen ice packs. While they provide reliable cooling for several hours, they can cause frostbite if worn directly against the skin and will make your costume wet.
Evaporative Cooling Vests
These vests work by soaking in water and then wring out. They are easy to use but have limited cooling time and can make your costume wet. If you wear a full-body costume, never wear Evaporative Cooling Vests under your costume. They will contribute to your costume's humidity and make you hotter instead of cooling you down.
Active Cooling Vests
The most advanced and expensive option, these vests use recirculating chilled fluid to keep you cool. They offer excellent cooling but are not very portable and require a power source, making them less practical for most costume activities. The wires, fans, and noise they generate make them challenging for movie sets.
PCM (Phase Change Material) Cooling Vests
PCM cooling vests, the kind that ThermApparel makes, cool through conduction, offering reliable relief even in hot, humid environments where other cooling methods struggle. The PCM packs in the vest absorb body heat as they "melt" from solid to liquid and release that heat as they refreeze, maintaining a steady, comfortable temperature.
Why ThermApparel PCM Cooling Vests are Cooling Gear are Perfect for Costumers and Live Entertainment Actors
For costumers, live entertainment actors, performers, and cosplayers, ThermApparel PCM Cooling Vests and Cooling Grear are the ideal solution for staying cool without compromising the look or feel of their costumes.
Unlike traditional ice packs that can drop to freezing temperatures and cause discomfort, ThermApparel PCM Cooling Packs melt and refreeze at 70°F (21°C), providing consistent cooling without becoming too cold.
They are safe to wear directly against your skin, so there's no need for any additional barriers or protective layers. And because the cooling packs don't produce condensation, you don't have to worry about moisture or dampness affecting costumes.
Another key benefit is that ThermApparel Cooling Vests and Cooling Gear operate without batteries, wires, or noisy fans, allowing them to remain silent and unobtrusive, even on film sets or during live events. ThermApparel PCM Cooling Packs actively support your body's natural cooling process by cooling your blood as it flows over the Cooling Pack. Your body then circulates that cooled blood throughout your body, helping to maintain a balanced core temperature and keeping you focused, comfortable, and dry throughout your performance.
Integrating Cooling Vests Into Your Costume
When integrating a cooling vest into your costume, it's essential to consider how the vest will fit and interact with your outfit. For example, a Mrs. Claus fitting for her new costume discovered that wearing UnderCool 3 added approximately one inch to her waist measurements. This extra space ensures a proper fit while accommodating the cooling vest. We recommend taking your measurements with and without wearing the cooling vest of your choice.
Our cooling solutions adapt to a wide range of costume types. Whether you're wearing a superhero suit, period costume, elaborate cosplay, or full-body mascot, you can integrate ThermApparel Cooling Vests for a comfortable fit. The low-profile designs ensure that wearers stay cool while maintaining the aesthetic integrity of their costumes.
Here are some considerations for making ThermApparel PCM Cooling Vests work with your costume.
Tight or Form-Fitting Costumes
For tight or form-fitting costumes, such as superhero suits, you may need to make small adjustments to fit the cooling vest comfortably. Adding about an inch to your measurements can help accommodate the vest. Also, consider incorporating a layer or a strategic prop to conceal the cooling packs if they are visible. In skintight costumes, cooling packs may be noticeable on your back.
Heavier Costumes
For more substantial costumes like armor, full-body suits, or historical attire, we recommend the UltraCool or RallyWrap Cooling Vests. You should plan for at least two to three inches in length and depth for your pattern to ensure the vest fits comfortably without compromising the costume's structure or appearance.
Retrofitting Existing Costumes to Include Cooling Vests
If you're adapting an existing costume to include a cooling vest, evaluate whether your current attire can be adjusted. You might need to modify the fit by altering seam allowances, adding or expanding darts, or inserting a gusset or small panel to accommodate the vest comfortably.
Extra Adjustments for Enhanced Cooling
Some costumes require more than just a cooling vest to prevent overheating. Consider additional modifications to improve airflow, such as incorporating panels or vents. Increasing airflow will significantly boost comfort. For example, adding a ventilation flap could have relieved characters like Chewbacca during long takes. Similarly, installing small fans at the base of R2-D2 would have helped circulate air inside the costume. By thinking creatively about airflow, you can significantly enhance cooling and comfort.
About ThermApparel PCM Cooling Vests
ThermApparel's PCM cooling vests fit seamlessly under costumes without adding bulk, ensuring they are discreet and photo-friendly. The low-profile design allows you to move freely and maintain the aesthetic of your costume without the cooling vest being visible or causing discomfort.
These cooling vests are lightweight and easy to recharge—they take just 30 minutes in ice water or 60 minutes in a freezer or refrigerator–and they require no electricity, cords, or fan. This makes them completely silent and ideal for long-lasting cooling during extended performances, events, or hot environments.
ThermApparel offers five different types of PCM cooling packs. Visit the Cooling Packs webpage for full descriptions. ExtendedCool and SlimCool packs are articulated to move with your body, ensuring comfort and flexibility without adding bulk.
ExtendedCool: The "Workhorse" Cooling Pack
If you're suiting up for a full day at a convention or preparing for an outdoor performance, ExtendedCool is your go-to cooling pack. It's the "workhorse" of the group, offering 2-4 hours of cooling and versatile enough to be used with our three main products: UltraCool, RallyWrap, and UnderCool 3. It moves with your body, making it ideal for costumes that require flexibility or more extensive coverage. Whether you're portraying a full-body character like Santa, a furry, or a mascot, ExtendedCool handles the heat, fitting comfortably under your costume and keeping you cool during long, demanding performances.
SlimCool: The "Secret Agent" Cooling Pack
For costumes that require a sleek fit, SlimCool is your secret weapon. Offering one to two hours of discreet cooling, it stays hidden beneath form-fitting outfits, ensuring you remain cool without disturbing the smooth lines of your costume. Whether you don a superhero suit or a corseted dress, SlimCool delivers relief without sacrificing style. For those tight-fitting costumes like spandex suits or layered looks, UnderCool 3 paired with SlimCool is your go-to combination, providing cooling comfort that moves with you while staying entirely out of sight.
Understanding ThermApparel's Choice of Fabrics
The fabrics used for ThermApparel cooling vest garments were well thought-out and tested. The vest easily stays in place with the athletic binding and lightweight, slim straps. Because of the athletic binding, the UltraCool and UnderCool 3 can stay up by themselves; there is no need to wear the straps.
All our garments use 4-way stretch Spandex because of its exceptional flexibility and comfort. They stretch lengthwise and crosswise, allowing for a greater range of motion and a more comfortable fit. This makes them ideal for ease of movement, especially for close-fitting garments.
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Enhanced comfort and freedom of movement: Moves with your body, reducing restrictions and allowing for a more natural, flexible and comfortable experience.
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Improved fit and shape retention: It hugs the body without feeling constricting and maintains its shape even after repeated stretching and washing.
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Breathability: Offers good breathability, allowing for better airflow and moisture-wicking, keeping you cool and dry.
Our breathable mesh fabric offers several benefits to enhance comfort and performance by promoting airflow, moisture management, and quick-drying capabilities. They are especially beneficial in warm climates or during physical activities when staying cool and dry is essential.
- Superior Ventilation: The open structure of the mesh fabric allows air to circulate freely, promoting excellent ventilation and airflow. This helps to keep you cool and comfortable by allowing heat to escape easily.
- Lightweight and Comfortable: The mesh fabric is lightweight, contributing to overall comfort.
- Durability: Despite its lightweight appearance, the mesh fabric is quite durable, with interlocking or spaced out yarns providing structural integrity and resistance to wear and tear.
Breathoprene with a hook-receptive backing allows for a wide range of adjustability in sizing.
- Breathoprene: A breathable and perforated neoprene material allows air to pass through, reducing heat and moisture buildup while providing support and compression.
- Hook Receptive Backing: A layer of looped fabric attached to one side of the breathoprene allows it to be securely fastened and offers a wide range of adjustability.
Sizing for ThermApparel Cooling Vests
Getting the right size for your cooling gear is key to staying cool! Measure your natural waist—ignore the hips or pant size. Think of our cooling garments like a snug hug; they should fit closely to ensure the cooling packs make contact with your back.
- Sizing is based on your natural waist measurement.
- If you're between two sizes, choose the larger size.
- Down't worry about chest or cup size, it won't affect the fit.
- Check out our sizing page for more info, videos, and tips.
Choosing the Right ThermApparel Cooling Product
ThermApparel offers a lineup of cooling vests and wraps tailored to suit various costume types and individual preferences. Our products feature low-profile designs that fit seamlessly under your costume. They provide effective cooling without adding bulk and are photo-friendly, ensuring no lumps or bumps disrupt your costume's smooth silhouette.
Our cooling packs melt and refreeze at a comfortable 70°F (21°C), making them safe for skin contact and easy to manage throughout your day.
UltraCool 3
For maximum cooling in demanding conditions, UltraCool is your go-to solution. Designed for full-body costumes or heavy outfits worn for extended periods, UltraCool features ExtendedCool Cooling Packs that deliver superior heat management. Whether performing on stage under intense lights or navigating a bustling convention, this vest provides prolonged cooling and ensures you stay focused and comfortable without any bulk.
RallyWrap
For those who need adaptable and versatile cooling, RallyWrap is the perfect choice. This flexible wrap can be worn around the waist, shoulders, or limbs, offering targeted cooling exactly where you need it. It's ideal for costumes requiring a customizable cooling solution, giving you the flexibility to stay cool whether on the go or in a static position.
UnderCool 3
UnderCool 3 is a lightweight, slim cooling solution designed for discretion and comfort. Perfect for form-fitting costumes or situations where a low profile is essential, UnderCool 3 integrates seamlessly with SlimCool or ExtendedCool Cooling Packs. This cooling vest provides effective cooling without adding bulk or altering the costume silhouette, making it ideal for maintaining your appearance while staying cool.
CoolSleeve
For quick, targeted cooling, CoolSleeve is your best bet. It focuses on the radial artery in your forearm, delivering fast relief during pre and post-cooling needs. Lightweight and flexible, CoolSleeve slips easily onto your arm, offering discreet cooling that supports your performance without interfering with costume movement.
Headband
For flexible, targeted cooling around the head, the ThermApparel Headband features FlexCool dual-sided cooling packs that mold comfortably to your head, offering heat relief without compromising your costume's fit. It's ideal for performers needing head cooling that adapts to their movements.
Grab-N-Go
Grab-N-Go packs are the perfect 30-minute cooling relief solution. They can easily be tucked into pockets, between layers of armor, or even in your corset or sports bra. Essential for costumers or live entertainment actors who need to transition swiftly between roles or scenes, they provide immediate relief without slowing you down.
Keep a set in the freezer, ready for those unexpected moments when heat catches you off guard. Designed with performers in mind, our cooling packs work seamlessly with your costume, ensuring you stay comfortable and in character throughout your event.
Heat is a real danger for costumers, and live entertainment actors, so it is essential to consider cooling when creating and wearing costumes. ThermApaprel Cooling Vests and Cooling Gear are designed with costumers in mind.
Integrating PCMs into our products ensures efficient heat regulation, while the lightweight and discreet design allows for comfortable wear under even the most elaborate costumes. With ThermApparel's cooling vests and wraps, costumers can focus on delivering their best live performance, without the distraction of excessive heat.