Why 50-53 degrees?
After many years working with medical experts and testing different temperatures on industry personnel representing a broad spectrum of end users in the most hostile of work conditions, this temperature maintained sufficient energy to absorb a body's heat for several hours, yet was not too cold to be considered uncomfortable by the wearer. Testing on temperatures higher than 50-53 degrees were found ineffective for cooling over a light layer of clothing and did not possess enough watts of energy to be effective in absorbing body heat and reducing heat build up and core temperature.

Will 50-53°F degrees give my dog a false sense of cool?
No. The term "false sense of cool" is nebulous. One may assume the wearer may not be aware or understand that this temperature is completely safe for prolonged direct skin contact and will not harm soft tissue, cause constriction of superficial blood vessels or damage as can the temperatures of frozen ice or gel. The United States Sports Academy Sports Medicine Laboratory (Lehman 1990) studied soft tissues and optimal healing temperatures for prolonged cryotherapy. Their findings deemed the optimum healing temperature for prolonged cold therapy application is between 46°F and 54°F. Therefore, a 50-53°F temperature is certainly safe for continued use.

Why doesn't the vest continue to feel as cool after 30 minutes?
An energized vest will initially feel cool when you first put it on. Then as the body begins to expel heat into the cooling packs, the body heat begins melting the energized Heat Transfer Formula. You also begin acclimatizing to this temperature almost immediately as the body reacts positively. A body exposed to "too cold" temperatures (like ice or gel) reacts negatively by shivering to create rapid heat.

How come I still sweat when I'm working?
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 wanes considerably for all wearers in all conditions. If the percentage of humidity in the work environment is over 50-53%, you will notice more sweating than in less humid conditions where evaporation of sweat may go unnoticed (as in arid, desert like environments). However sweating 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 velocity (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 do I know its working?
Although the vest does not feel cold and you may only feel cool, most probably you are not sweating profusely and are not as hot and uncomfortable as you normally would be in that same situation, working without the cool vest. If you are wearing protective apparel and not wearing this cool vest, you will quickly notice the heat buildup that occurs inside this protective apparel. The heat buildup that occurs inside 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 apparel can be non‑porous offering 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 50-53° 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 unit?
The unit's cooling duration will differ among people and situations. When there remains a small clump of white energized Heat Transfer Formula left (about the size of a 5p piece) one or more cells of the vest are ready to be re-­energized.

If the bag breaks will the chemical hurt me or my dog?
No. The Heat Transfer Formula is an inert, non-toxic, non-carcinogenic, carbon based chemical that is virtually odorless and has the greasy consistency and feel of castor oil. It also weighs less than water of the same volume so the cooling pack will be positively buoyant. In its liquid state, if the cool pack should leak onto clothing or your skin, you should immediately remove the vest and wash the clothing and/or your skin with mild soap and water.

How do I clean the cool vest?
You may wash or wipe the packs with mild soap and water solution, isopropyl alcohol or any anti-microbial cleanser. The cooling pack that contains the Heat Transfer Formula is comprised of a medical grade polymer specifically designed to encapsulate this formula. 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.

Do I have to wear both packs?
No. However wearing both packs allows the body to expel twice as much heat. This would be especially important when wearing layered clothing and protective apparel that is either impermeable or possesses minimal porosity. The anatomic design of the cooling pack accommodates breathing apparatus and other equipment.

Why does it take longer to charge in a refrigerator or freezer than ice and water?
When the cooling pack is submerged in a container filled with ice and water, the pack is completely surrounded on all sides by a colder temperature. When the pack is laid on a shelf, only one side is touching the shelf, while the open side is exposed only to cooler air. Water is the beat thermal transfer medium while air is very poor at transferring cool or warm energy. The quickest method to charge the cooling pack is the ice and water method. This is also the feature that makes this technology man-portable for in-field use when electricity is impractical.

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

I left the cool vest in the boot of my car last night and it was still charged this morning, How come?
If the temperature outside is 50-53F or lower, this will cause the cool vest to either remain energized or begin to energize. Only when something that is warmer than an energized pack (e.g. the human body) comes into thermal contact with the pack, does the pack begin to absorb heat, begin to melt and return back to its liquid un-energized state.

Is the carrier fire retardant?
Yes, we can supply F.R. carriers and F.R. cooling packs.

How does this vest differ from using ice packs?
Greatly. 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 open the pores to sweat, inhibiting the body's natural ability to regulate itself. Also these temperatures usually cause a tremendous amount of condensation when melting and require a freezer at extremely low temperatures in order to make the ice or gel change its phase.