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London Build

20 Jul 2022

Too Hot to Work: Working Safely on a Construction Site During a Heatwave

Too Hot to Work: Working Safely on a Construction Site During a Heatwave
© Thanakorn Suppamethasawat
During a heatwave, there are a number of health and safety hazards that construction workers need to be aware of ' but when does it become too hot to work and how can we protect the wellbeing of employees?

During the'height of the summer, temperatures can soar, making working conditions more difficult. Amidst a rise in construction projects which were previously put on hold due to the pandemic, more construction workers are at risk of the side effects of working in hot conditions, not to mention the heat given off from equipment and construction processes. And those hazards become even more of a risk as temperatures increase.'

But what can be done to keep construction projects ticking along without it impacting the health and wellbeing of staff?'There are'hazards that workers need to be aware of during a heatwave'' here are a few of the ways that construction workers can stay safe, whatever the weather.'

Too hot to work: What do the government guidelines say about working in a heatwave?

The'Health and Safety Work Act 1974'states that employers must provide their staff with a healthy, safe work environment ' and during hot and dry conditions, this means controlling the risks that employees may face as a result of working in hot temperatures or exposure to the sun. There's no set maximum'temperature for working'outside in the UK, but employers are implored to use their discretion to provide a reasonable temperature for staff to work in and take action when necessary. It can be difficult to assess air temperature, since humidity, wind speed and clothing or PPE can all affect the temperature someone experiences. However, having equipment on site to assess the conditions more specifically, such as a wet bulb globe thermometer or the electronic equipment to measure humidity on site, can help ensure you're not missing anything.'

The'HSE site'defines that'thermal comfort'is between 13 and 30 degrees, and when more strenuous work is required, these temperatures should fall on the lower end of the spectrum. Construction companies need to take regular risk assessments to ensure that staff working in hot temperatures, or those who are exposed to the sun throughout the day, are protected against heatstroke, sunburn, heat rash and dehydration.'

What are the risks to our health in a heatwave?

Issues can arise when the temperature and humidity rises, and the first thing that people will notice is the physical effects.'Exposure to higher temperatures'can increase sweating, change blood flow and cause an increase in heart rate. But changes in temperature can also increase irritability, decrease concentration and have an impact on performance, making it harder for people to do their jobs well. What's more, manual work such as that found on a construction site will add to that heat and increase the burden the heat is placing on the body.'

Construction workers are more likely than most to be outside regularly, and when they are continually exposed to sunlight and UV radiation, they're put at an increased risk of skin cancer and burns ' particularly fair-skinned people and those who burn easily.'

Heat exposure can lead to several illnesses and conditions, including a heat edema which is a swelling that occurs, most typically in the ankles, when someone isn't acclimatised to the conditions. You might also notice heat rashes appear on the skin, cramping caused by a salt imbalance from excessive sweating, and exhaustion which can manifest as dizziness, visual disturbances, nausea and headaches. In more serious cases, the individual may experience'heat stroke which is a medical emergency'and can lead to a loss of consciousness, confusion and even convulsions. Heat stroke requires immediate medical attention, because delaying treatment can have serious consequences that can result in fatality.'

Who is most at risk when working during a heatwave?

It's not just working outside that puts all construction workers at risk, but there's the presence of heavy machinery, lifting materials and driving that increase temperatures and heat stress even more. Heat can be a real concern for workers whose job involves driving, not least because they become a hazard to themselves and those around them if fatigue sets in or they pass out from the heat. Employers should provide vehicles with air conditioning or avoid driving altogether if the temperatures are very high.'

Working in sweltering conditions all day is not only uncomfortable for staff but it's also incredibly dangerous and can lead to severe situations where the'health and safety'of individuals and those around them is put at risk. If a construction worker is using dangerous equipment or tools and falls ill from heat, the consequences can be dire. Employers have to be sure that the environment for their workers is safe and that means regularly assessing the temperature to make sure employees are not at risk of heat-related conditions and illnesses.'

How can employers protect construction workers during a heat wave?
  • Making sure staff are'drinking plenty of fluids'and are taking regular breaks to fully hydrate is essential on a hot day. Staff need to have access to free, cool water at all times.'
  • Staff need to be'dressed appropriately'not just for the job at hand but also for the weather. This means wearing engineered fabrics that will wick sweat away from the body and reduce heat load on the body, while also wearing clothing and'suitable PPE'equipment that will'protect against UV rays'and on-site equipment. A nape protector, or a wrap-around sun visor, will help to protect the face and neck, and all staff should be supplied with head coverings.'
  • Prevent staff from overdoing it in the heat. It's important that staff pace themselves and'take more breaks'than normal, with the understanding that jobs will naturally take longer to complete due to the stress of the heat.'
  • Supple'sun creams'so that people who are'exposed to the sunlight'all day can protect themselves as much as possible, especially'fair-skinned people who tend to burn more easily.'
  • Where possible,'reschedule outdoor work'to cooler times of the day and avoid working in the sun when it's at its highest and therefore hottest.'
  • Introduce shading'so that staff have somewhere to rest up and cool off during the day. This may be an area inside with air conditioning where possible, or a tented area with ample shade from the sun. If possible, introduce shading in areas where employees are working too.'
  • When staff aren't working, encourage them to remove their PPE so they can encourage heat loss and cool off more quickly.'
What are the signs of heat exhaustion?

One of the primary ways of protecting against on-site hazards is by knowing the warning signs of heat exhaustion and other heat-related conditions. These illnesses can range considerably in severity and shouldn't be taken lightly under any circumstances. The warning signs to be aware of, and watch out for in all colleagues, are:

  • Heat cramps which are typically caused by poor hydration; in these instances, staff should take a break, drink plenty of water and elevate their feet
  • Heat exhaustion: staff should go somewhere cool, rehydrate and rest
  • Heat stroke ' call 999 and seek medical advice immediately

As part of the thermal comfort risk assessment, employers should evaluate the environment and continually reassess throughout the day as temperatures and conditions change, and different work activities take place. Protecting staff against the dangers of higher temperatures isn't a one and done task ' it's something that needs to be taken into consideration throughout the project and on a frequent basis.'

Staff should be rotated regularly to give everyone equal break time and a rest from the sun, and physically demanding work should be rescheduled to a cooler time. Similarly, managers need to make sure that staff are continuing to use equipment safely and are still wearing the required PPE to keep the site safe.'

Working in hotter temperatures may not have been as much of a concern several decades ago, but as the climate crisis pushes up temperatures year on year, it's something that construction workers in the UK need to place more focus on in order to keep staff safe.'

There are many risks associated with working outdoors in hot temperatures, and since construction workers are more likely to be working outside, they need to take precautions to avoid heat-related issues arising.

An'employer's failure to keep the work environment safe is a breach of health and safety'regulations, and could even'result in prosecution and fines. Everyone needs to heed the relevant guidance to stay cool, hydrated and safe at all times.'

Source: Charles Tack for PBC Today