Why isn't colder ice or gel better?
After many years working with medical and veteranary experts and testing different temperatures on industry personnel and working dogs representing a broad spectrum of end users in the most hostile of work conditions, the temperature levels maintained by CoolZone Dog's cooling vests were found to be the optimum for absorbing a body's metabolic heat for several hours, without causing cold injury side effects or discomfort. Ice and gel packs are so cold that they can cause permanent nerve and tissue damage in the form of frostbite or non-freezing cold injury if placed in direct contact with the skin or applied for more than 20 minutes. Additionally the body responds to these colder temperatures by closing off capilary blood vessels in the skin, actually reducing the amount of heat it can expell.

Why doesn't the vest continue to feel as cool after 30 minutes?
An energized vest will initially feel cool when you or your dog first puts it on. The body quckly adjusts and the temperature begins to feel normal, although the HTFx^tm UniPaks^tm, are continuing to absob metabolic heat from the body, reducing the need to sweat (humans) or pant (dogs) to maintain a stable core temperature. Heat stress is reduced because the body does not have to expend as much energy and resources (water, electrolytes, etc.) to stay cool. A body exposed to "too cold" temperatures (like ice or gel) reacts negatively by shivering to create rapid heat, and constricting blood vessels in the skin to trap heat in the body's core.

Why do I still sweat when I'm working while wearing a cool vest?
Several variables play into the complex biological equation that works hard at helping the body maintain thermal regulation. Some people may continue to sweat while wearing this vest, but usually sweating decreases considerably for all wearers in all conditions. If the percentage of humidity in the work environment is over 50-53%, even minimal amounts of sweat will become more noticable because the sweat cannot evaporate as quickly in arid, desert like environments. The amount of sweat produced will be greatly reduced as the body continues to expel heat into the cool vest easing the burden on the body's cooling mechanisms. Just as each human is unique in their DNA makeup, so is the level of tolerance to extreme heat and/or the wearing of protective clothing. These variables play an important role in understanding the thermal burden that is placed on the human body, especially noted with wearing protective apparel. And, each day the body may react differently depending upon the following:

• The type of clothing or protective apparel or equipment you are wearing, and
• the ambient temperature and humidity or heat index measurement, and
• the caloric energy your body is expending to complete the task, and
• whether you are working in direct sunlight, radiant or reflective heat, and
• whether there is moving air in the surrounding environment, and
• whether you are sufficiently hydrated, nutritionally balanced and in good health, and no contravening health problem exists to alter this equation.

How will I or my dog feel after wearing the cool vest all day?
Let's assume that you wear the cool vest because you work in a hot environment or wear some type of protective apparel. Next, we'll assume that you also generate increased metabolic heat when conducting the work, you should feel much more energetic and vigilant than under similar circumstances without wearing the cool vest. When the body's sweat and or panting response has been reduced, fewer electrolytes, minerals, salts and other nutrients are not as readily forfeited. The body has retained these nutrients for future use to promote proper muscle function, neurological activity and other bodily functions.

Why all this talk about sweat, dogs don't sweat do they?
Actually they do. Dogs are able to expel excess body heat by sweating through the pads of their feet, although their primary means of cooling is panting which also reduces electrolytes, minerals salts and nutrients, as well as generating metabolic heat through the muscle activity needed to move the diaphragm and rib cage rapidly.

How do I know the cool vest is working?
Although the vest does not feel cold and you or your dog (depending on who's wearing a vest) may only notice the fact that you don't feel overheated. Most probably you are not sweating profusely or your dog is not panting as much and is/are not as hot and uncomfortable as you normally would be in that same situation, working without the cool vest. For fire or search and rescue workers working with canines, there is the added heat stress of protective garments. If you are wearing protective apparel and not wearing a cool vest, you will quickly notice the heat buildup that occurs inside the protective apparel. The heat buildup that occurs inside personal protective equipment (PPE) is called the micro-environmental temperature. Wearing impermeable protective apparel/equipment can create a rainforest effect (with the humidity factor of 99% on the inside), as the typically non-porous apperrel offers no means to dissipate heat from the body or assist in the evaporation of sweat. If on the other hand, you wear impermeable protective apparel/equipment with the Cool Zone vest, you will immediately notice the difference. There will be a noticeable reduction in the micro-environmental temperature inside the PPE, a substantial reduction in moisture content; and your bodily heat dissipating mechanisms aren't being overworked to keep you thermally regulated. When wearing the cool vest under PPE, fogging in headgear, facemasks and other equipment is virtually non­existent.

How come I don't get as tired later in the day?
As previously mentioned, the less electrolytes and minerals that your body forfeits, the less energy you had to expel in an effort to keep yourself thermally regulated in the heat stress situation. Therefore, more energy remains stored for later use.

How do I know when to recharge the UniPak?
Due to differences in metabolism, body mass and environmental conditions, the vest's cooling duration will differ among different people, dogs and situations. As long as any of the HTF Exotherm^® in the pack is still white in color, it is still partially charged and will absorb heat from the body.

If the UniPakruptures, will the chemical hurt me or my dog?
No. A rupture of the UniPak is highly unlikely. HTFx UniPaks are constructed by an FDA registered manufacturer from an incredibly durable medical grade tripolymer film. The US Air Force has put our UniPaks through extreme durability testing, including running them over with military trucks with no ill effect. If an HTFx UniPaks is somehow cut or punctured, the HTF Exotherm inside is not toxic, carcinogenic or corrosive, and is approved by the FDA for direct contact with food. It is inert at room or outdoor temperatures. It also weighs less than water of the same volume so the cooling pack will be positively buoyant. HTF Exotherm can cause mild irritation to people or animals with sensitive skin, and should not be eaten. If In its liquid state, if a UniPak does become damaged and should leak onto clothing or your skin or your dog, you should immediately remove the vest and wash the clothing and/or exposed skin or fur with mild soap and water.

How do I clean the cool vest?
You may wash or wipe the UniPaks with mild soap and water solution, isopropyl alcohol or any anti-microbial non-abrasive cleanser. The fabric vest carrier may be washed in mild soap and water. Lay flat or air dry the carrier, as hot dryers will crimp the Velcro and elastic straps.

Why does it take longer to charge the UniPak in a refrigerator or freezer than when submerged it in ice and water?
Water is more dense than air, and able to absorb heat out of the UniPak more quickly than the thinner air in a refrigerator or freezer.

How long will a charged pack stay charged in an empty cooler or container?
If the container is adequately insulated (eg: sports cooler), a charged pack may last for several hours (e.g. 24 hours or longer). If several charged packs are packed together, one on top of another and placed in an insulated container, the inside packs may remain charged for several days, depending upon the environment and situation.

I left the cool vest in the trunk of my car last night and it was still charged this morning, How come?
If the temperature outside is 55F or lower, this will cause the UniPaks to either remain charged or to recharge by giving off the heat it has trapped. Only when something that is warmer than an the charged pack temperature (e.g. the human or canine body) comes into thermal contact with the UniPak, does the HTF Exotherm begin to absorb heat.

Is the cooling vest fire retardant?
It can be. Fire retardant carriers and inserts are available as special order items.

How does this vest differ from using ice packs?
Temperatures of ice and gel (usually 32°F and lower) can cause frostbite, ice burn, cold shock and pain. These temperatures readily cause constriction of the blood vessels so the body can't radiate heat from the skin, inhibiting the body's natural ability to regulate itself. Also these temperatures usually cause a tremendous amount of condensation in humid environments.