Add more ice packs on top, if there is room. The next layer is eggs, dairy and other perishable foods. Make sure all liquids are in sealed jars or plastic containers that don't leak. Next, layer in fruits and vegetables.
Ice packs on the bottom or side of your cooler will do a great job of keeping the sides and bottom of your cooler cold, but it won't do much for the food you're trying to chill. Put the ice packs on top.
Heat rises, cold travels down... ice should be on the top for best cooling. Buy dry ice, lasts long time for food and regular ice for drinks cooler. Drinks in water as ice melts will be nice and cold.
Cubed ice is best for more effectively chilling items, while block ice will last much longer. For most uses, a combination of both works the best. Start with one or two blocks of ice, fill the remaining space with the items you want to keep cold, and then add the cubed ice at the end.
Block ice will melt slower and keep your cooler cold for longer. Cubed ice will wrap around all those beverages, keeping every can or bottle cold. Place blocks of ice along the bottom of the cooler first. If you can't find blocks of ice, you can make your own by freezing a large container of water.
Place ice bags over as much of the body as you can. Ice packs against the neck, under the arms, and in the groin area, where large blood vessels lie close to the skin surface, will help quickly cool down a victim of heatstroke.
As we probably all remember from our school days, cold travels down and heat moves upwards. On that basis, with science in mind, you'd be best off with a layer of gel packs across the top of your contents so they continue to radiate cold down towards your food and drink.
The ice packs can be placed in the water tank at the bottom or two can be placed in the top water tank under the lid. Fill the water to the level but remember to replace the rubber bung.
Gel packs freeze at a lower temperature than ice and generally last longer than ice. The length of time it can remain frozen varies based on the size, shape, temperature exposure, and how you are packing a shipment/cooler.
It is recommended to keep the dry ice at the bottom of your cooler. If your cooler is big enough, a solid block of dry ice is recommended, but cylindrical pellets are a good substitute. Keeping the dry ice at the bottom allows the food at the top to stay cool without freezing.
Apply cold pressure strategically
If you're going to slap an ice pack or bag of frozen peas anywhere on your body, then press it against the pulse point on your wrist, neck, chest, or temples. They're the spots that release the most heat from the body, and where the veins flow closest to the surface of the skin.
The best place to position your air cooler is right in front of the window. Hotter the air, faster the evaporation and cooler the air blown out by the fan. It's also important to create good ventilation in the room to push the humidity out. In order to do this, you need to open windows in the room.
Layer items with ice packs or bags of ice. Start with a layer of ice packs or ice on top of the insulation. Place drinks and items you'll use frequently on top of this layer. Add another layer of ice packs or ice, and then put in perishable items like fruits, vegetables, dairy products, and meats.
It's convenient to pack it on the bottom, but it will last longer packed on top. Remember to minimize those air pockets when packing the cooler. You can fill in these air pockets with regular ice. Dry ice can be used with cubed or block ice.
Always keep a cloth between your skin and the ice pack, and press firmly against all the curves of the affected area. Do not apply ice for longer than 15 to 20 minutes at a time, and do not fall asleep with the ice on your skin. Commercial cold packs are too heavy and bulky for use on or around the eye.
Greater than 20 minutes of icing can cause reactive vasodilation, or widening, of the vessels as the body tries to make sure the tissues get the blood supply they need. Studies have also shown 30 to 40 minutes in between icing sessions are needed to counter this reaction.
Put the ice-packs upright in the freezer compartment of the refrigerator, so that the surface of each ice-pack is touching the evaporator plate, and close the door.
The layers in your cooler will create zones that go from really cold down at the bottom to chilled up at the top. Start your layers with block ice down at the bottom of your cooler. Then add any frozen goods and the goods you need to keep very cold, like raw meat.
Keep your cooler out of direct sunlight when possible. Ice can last up to twice as long in the shade. Some pros even use tarps or towels to cover their coolers when they can't find a shaded spot.
Use Dry Ice as Well as Regular Ice
Place the dry ice at the bottom of your cooler and then layer with regular ice over the top. The dry ice will help cool down the regular ice and will turn into gas as it melts, leaving no unwanted messes or excess water to clean up after.