Keeping Cool at the Construction Site
When people think Canada they probably aren’t thinking a beautiful sunny paradise – But for a couple of months a year, it actually does gets hot outside! Summer has arrived, and parts of the country have already seen record or near-record highs this month & meteorologists say 2020 on course to be one of the hottest years since records began
The risk is increased for workers where the temperature can reach higher than the outside air temperature such as those performing roof work, road construction or doing interior work on a building with no air conditioning and poor ventilation.
Here are some tips that both employers and employees can use to keep cool, comfortable, and therefore safe when the weather rises.
Work in Extreme Temperatures: Legislation
Legislation can be a bit vague surrounding the rules and regulations on what employers specifically must do to keep employees safe with regards to heatstroke, and often these standards & regulations will differ provincially.
Generally, there is no specific temperature federally in Canada where work can’t be performed, however, the temperature might be a risk factor for potential hazards that make work unsafe to perform. In these cases, employers and employees have a responsibility to adjust conditions, or the right to refuse work if the temperature creates hazards.
The reason for this? There are factors that contribute to exposure limit (the time a worker can safely be exposed to a condition like heat) beyond just the temperature. Some of these are:
- Relative humidity
- Exposure to other heat sources
- Air circulation & flow
- Demands of work
- If workers are acclimatized to the workload under the conditions
- If workers have proper clothing & PPE
- Amount of work compared to the number of breaks
There isn’t one magic temperature where work is canceled, but each province does have some legislation that describes temperatures suggested for different workplaces & conditions, particularly those in industrial jobs such as construction workers.
Another way employers, managers or supervisors might determine if the heat can be dangerous is to use TLV® Values. Sometimes these are used as legislation, and sometimes as guidelines provincially.
This table represents the criteria for workers’ exposure to heat stress, and are used as a guideline (and sometimes legislation) for employers to determine when work can be unsafe.
It’s also worth noting that TLV® Values are subject to change annually. Work levels are defined as:
- REST: Sitting
- LIGHT WORK: Sitting, standing to control machines, light hand or arm work
- MODERATE WORK: Moderate hand & arm work, light pushing or pulling,
- HEAVY WORK: Intense arm & trunk work, pick & shovel work, digging, carrying, pushing/pulling heavy loads and walking at a fast pace
- VERY HEAVY: Intense activity at fast to maximum pace.
What Heat Does to Your Body
Heat does more than give you a burn (that’s bad, too—we’ll get into that later) which can result in vomiting. fainting, and is the worse cases, even death.
A healthy, normal human body maintains an internal temperature of 37°C, and generally feels most comfortable with an air temperature between 20°C-27°C, and humidity ranges from 35 to 60%. As the external environment warms, the body warms, too. Your ‘internal thermostat’ will introduce more blood to your skin and produce more sweat. This means the body increases the amount of heat it loses to make sense of the heat burden.
When environments are hot, the rate of ‘heat gain’ is more than the rate of ‘heat loss’ and the body temperature begins to rise. This rise results in heat illnesses.
When your body begins to heat up too much, you may become:
- Unable to focus or concentrate on mental tasks
- Loss of ability to do skilled tasks or heavy work
Over-exposure to heat can lead to:
Heat Edema: Swelling (typically in the ankles) caused by work in hot environments.
Heat Rashes: Inflammation, which causes tiny red spots that prickle during heat exposure due to clogged sweat glands.
Heat Cramps: You might feel sharp pains in muscles in addition to the other symptoms of heat stress we list above. Cramps from heat are caused when your body fails to replace lost sweat with salt, and often happen when you drink too much water and don’t replace it with enough salt (electrolytes).
Heat Exhaustion: Caused when you lose body water and salt from excessive sweating. Symptoms involve heavy sweat, weakness, dizziness, visual disturbances, intense thirst, nausea, headache, vomiting, diarrhea, muscle cramps, breathlessness, palpitations, tingling, and numb hands & feet.
Heat Syncope: Heat-induced dizziness and fainting caused by insufficient blood flow to the brain while someone is standing. This usually happens when people aren’t used to an environment (are unacclimatized) and your body loses body fluids through sweat, blood pressure lowers & blood pools in the legs. Luckily, recovery is very quick when you simply rest in a cool area.
Heat Stroke: This is the most serious type of heat illness. Signs of heatstroke include a body temperature over 41°C and a complete/partial loss of consciousness. There are two types of heat stress, one where the victim does not sweat and the other, where they do sweat.
Heat Stroke: What Employers can do
As an employer, you have a responsibility to create the safest environment for your workers as possible.
Employers of workplaces under federal jurisdiction have the responsibility under clause 25(2)(h) of the Occupational Health and Safety Act to take every precaution reasonable in the circumstances for the protection of a worker. This includes precautions to protect workers while working in heat, or with processes that use heat.
Here are some things employers & employees can do to make work in heat more comfortable:
- Use fans or other mechanical cooling measures
- Wear light, loose-fitting clothing
- Increase break frequency and reduce laborious physical activity when peak temperatures emerge
- Drink cold beverages without salt, caffeine or alcohol, which can dehydrate you
- Implement measures to create shade—For example, umbrellas, screens or tents
Heat Stroke: What Employees can do
Here are some tips & steps employees should take to protect themselves from the heat at work:
KNOW THE SIGNS
- Recognize the signs of heatstroke, not just for yourself, but your coworkers, too. People suffering from heatstroke often don’t see their own signs, so being able to notice symptoms in others will help keep everyone on-site safe.
- Symptoms of heatstroke include:
- Dry, hot skin
- Partial to complete loss of consciousness
You Notice That Someone has the Signs of Heat Stroke—What Should I do?
These are some first aid measures you should use when you see someone suffering from heat-related symptoms.
- Call 911
- Move them to a cooler location with shade
- Stay with the person until help arrives
- Remove shoes, socks & as many clothes as possible
- Apply cool water/cloths to their head, face, neck, armpits & groin
- Do not force the person to drink liquid
6 Herc How-To Top Tips for Keeping Cool
1. Let Your Body Acclimate
Especially if you are a new worker or returning from any sort of extended leave due to illness or vacation – it’s important to let your body acclimate to work when in heat. All workers should expect work to be a bit harder in the heat near the beginning of summer, but as time goes on your body will adjust. Employers should expect and allow employees to work at a slower pace, slowly working up to 100% over 5 to 7 days so your body can adjust to the heat and strenuous activity.
2. Get an Early Start
Air temperature usually peaks between 3:00 pm and 6:00 pm, so the early bird gets the cooler worm! Try to schedule your jobs/days in a way that outdoor strenuous work can be completed early in the day. You’ll be in the best position if your days can be structured to be completed before these hot hours, but even just leaving the easier, or inside, work for these hours of the day can help you survive the heat.
Whenever you are working outdoors you should be using sunscreen. Even on cloudy and overcast days, ultraviolet (UV) rays can reach you and cause sunburn. When working outside you should reapply often with a sunscreen that is either sweat-proof or waterproof to help ensure that you don’t sweat it all off in the first few minutes of work. It’s also a good idea to wear a wide-brimmed hat to block the sun’s deadly rays.
4. Proper Clothing
When working outside doing strenuous activity in the heat, light-colored, loose-fitting and lightweight clothing is the way to go. Choosing natural fibered clothing such as cotton is a good choice as it will be more breathable and will absorb moisture well. Moisture-wicking clothing is also a smart choice, as it will draw sweat off your body which will allow your body to cool quicker – this is especially important if you work in a humid climate where sweat evaporation becomes difficult.
5. Hydrate, Hydrate, Hydrate
When working in hot weather conditions you should be drinking water or other fluids at least every 15-20 minutes. Cool water should be your main source of hydration. Sports drinks and coconut water are good options for restoring electrolytes and fresh fruits or fruit juices are good options if you’re feeling a drop in blood sugar. You should avoid coffee, soda, and alcohol as they all contain diuretics which will cause you to become more dehydrated.
If you experience any of the following symptoms you should immediately take a break to rehydrate:
- increased thirst
- dry mouth
- swollen tongue
- inability to sweat
- decrease in urine output
6. Take Frequent Breaks
Taking frequent breaks in the shade is an important step to avoid heat-related illnesses. Whenever you are feeling overheated or presenting any of the above symptoms of heatstroke, you need to take at least a 5-minute break in a shaded area. This is also a good time to rehydrate or eat some food to restore your energy.
To really cool your body temperature down, try getting inside an air-conditioned space like a vehicle or job site trailer. You can also apply a cool, wet cloth to pulse points on your body such as the neck, wrists, and elbows. If you are working indoors with no air conditioning consider setting up some portable fans to increase air circulation and cool you off. There are also a number of personal cooling devices on the market like cooling vests or neck coolers that can help you beat the heat.