Summer 2013

By Sue Yost — June 10, 2013

As we wait (oh, so impatiently) for winter to finally withdraw its fangs and let us get into the familiar warm weather rhythm of grass- cutting, gardens, pools, and summer clothing, it is time to once again ponder the implications of summer temperatures, and their effect upon your performance. Summer means no more bundling up just to go out for a few minutes, no more winter tires, shoveling snow, and trying to work on aircraft outside, with cold tools, thick sluggish fluids, and frozen fingers/nose/toes (or whatever else you may have exposed). However, summer will bring its own set of problems, such as heat-induced fatigue, hot metal surfaces, asphalt and concrete ramps that accumulate heat, salt sweat that stings your eyes, and a whole list of heat related performance inhibitors.

Human factors have always been a combination of what can go wrong (errors), what will be the cause(s) (factors), and what you can do to prevent things from happening (safety nets). And since this seems to work quite well for prevention of errors due to the Dirt Dozen factors, let’s use the same approach to overheating (may as well use what works).

You all know that heat will make you feel tired, sluggish, slow you down at work, and can make you feel physically as well as mentally baffled by the end of the day. This will affect the majority of the workforce, but there will be some of you who are more likely to feel the effects of summer temperatures, and will be affected sooner. People who will suffer the most will be those who:

•   have high blood pressure or heart disease
•   have poor circulation
•   are dehydrated
•   are overweight
•   are on certain medications, such as diuretics, sedatives, tranquilizers, and antihistamines, as these affect your ability
to perspire and cool down naturally (these are the most common, but this is not a complete list)
•   Are engaged in high activity jobs, or working out in direct sun
•   Need to wear heavy protective clothing that doesn’t “breathe”

Also, when you are working into the evening, and sun goes down, it should cool off a little, but if you are outside on the tarmac, the heat that has collected there all day will start to release, and may not give you the relief that you had expected (and looked forward to) so you’ll be working at temperatures that are significantly higher than the surrounding area.

There are the common signs that you are overheating, such as sweating, headaches, feeling tired and sluggish, and taking longer to get things done. Management needs to recognize that this will happen, give you more frequent breaks, access to water, and longer time deadlines for work to be completed. But what about some of the other symptoms that you may feel?

•   brain fog due to dehydration; there will be headaches, poor balance (really nasty if you are up on a wing), poor short term memory, and impaired decision making

•   pain and joint swelling (also the result of dehydration), will affect the cartilage that protects the bone surfaces at joints, making movement awkward and painful
•   muscle pain (dehydration again); water enables the body to dilute toxins that will remain trapped when the lymph glands become blocked due to poor circulation

•   cravings: yes guys, cravings, and not ice cream and pickles; cravings can happen when you are chronically fatigued, and are most commonly for items such as alcohol, caffeine and sugars;  drink at least 4 pints of water daily, and you will notice that you will have fewer cravings, and can more easily distinguish between food and thirst requirements.

•   immune dysfunction: most common in those of you who suffer from chronic fatigue, dehydration results in excessive histamine production, which can trigger allergies, and also interfere with the body’s ability to resist infections.

The message here? Not rocket science, is it? DRINK LOTS OF WATER! This will help with a multitude of summer-related issues, including thirst, memory improvement, increased ease of movement, better energy and cooling, and the relief of hunger pangs. Water is also good ON the body, not just IN it! Dunk your head under a tap, spray water down your arms and legs, wrap a cool wet cloth around your neck, and use a spray bottle to “mist” yourself regularly. It is much easier to stay cool than to cool down. And do not grab the coldest water buried in ice at the bottom of the cooler because your stomach will cramp. Try for room temperature water. Your body cannot absorb, and use, the water you drink until it comes up to body temperature.

Also important is eating. Brekky is an important meal, feeding your fuel-hungry brain that uses up to 30% of the day’s calories. Eat proteins and carbs in combination, using whole grain and brown breads, muffins etc., to give you longer, lasting energy reserves. Protein-rich foods will also help with alertness, attention, and motivation.

Caffeine is the beverage of choice for most of you, so use it judiciously. Too much over time will make your system immune to that “jolt” that you want, and you have to use more and more to get the same feeling. Try coffee in the morning, to get going, and follow it with water or juice to avoid the dehydration that will follow, and then maybe a cup for afternoon break, when that 12-hour cycle kicks in, and your circadian rhythm is falling, again chasing the coffee with a non caffeinated drink.

Last but not least are the non-food ways to stay cool. Loose, light-colored clothing that breathes, the use of fans, removing hats during frequent breaks and at lunch to allow heat to escape from your head (40-50% of heat loss), and getting out of the direct sun.

How do you know you are suffering from a heat-related emergency? Heat cramps and exhaustion will start with muscle cramps and feeling hot and tired, progressing to headaches, nausea, fatigue, and lots of sweat. These need to be addressed and the person cooled down, but if the person is hot with dry red skin (no sweating), and has bizarre, irritable behavior, rapid shallow breathing and a rapid and weak pulse, they are suffering from heat stroke, and could also have seizures. This is a 911 emergency. Have them take sips of water at room temperature, and cool them down as much as you can while waiting for the ambulance. Put covered ice packs in the groin, armpits and around the neck to cool down major arteries.

Heat-related emergencies are just that: emergencies of varying degrees. Prevention is the best thing, but when you are stuck in working conditions where you are likely to overheat, take the time to cool down, watch for signs and symptoms in yourself and co-workers, and have lots of the safety net that can help you – WATER!!

About The Author

Sue Yost

SUE YOST is the owner and principal instructor for HPA Consultants, based in southwest Ontario. HPA conducts Human Factors training, initial and update, and also for pilots doing elementary work, and QA workshops, both classroom and online. HPA offers CARs courses, CRM, and SMS, First Aid and WHMIS. The company has added ‘Effective Auditing,’ a two-day course for anyone conducting internal or external audits, or responsible for the implementation of quality management procedures of an aviation company. Contact HPA Consultants at (519) 674-5050 or

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