Many people view heat only as a nuisance factor or a ‘normal’ occurrence to be tolerated, rather than as a modifiable risk factor influencing health and learning. This perception needs to change.

Young people are at the forefront of climate action and South Africa is no exception. As protest action takes place around the country to coincide with the global #ClimateStrike movement this month, it is worth pausing to consider how South Africa’s 15 million school goers – more than a quarter of the population – are already being affected by climate change in this region.

South Africa is warming at twice the global average and is now considered to be a climate change ‘hot spot’, with rising temperatures, droughts, flooding, and unpredictable weather systems set to become the new normal. Consider, for a moment, what this means for children at school.

It’s a sad reality that many schools in the country continue to teach children in classrooms made out of converted shipping containers or prefabricated sheeting with corrugated iron roofs. Most container classrooms have poor insulation and little natural ventilation. A study in Johannesburg, which has a relatively mild climate, found that temperatures reached as high as 47.5°C in the containers and the large majority of students reported experiencing heat-health symptoms every day, including drowsiness, poor concentration and thirst. And overcrowded classrooms mean that the children themselves generate a considerable heat load. Some schools in South Africa have as many as 50 children in a class, making for intolerable conditions. Heat exposure can increase irritability, aggression and violence, a major concern given the rates of physical and sexual violence in schools in SA, both pupil-on-pupil and between teacher and pupil.

Not surprisingly, educational performance suffers under these conditions. In a recent review involving 18 studies, the authors calculated that students in classrooms with an indoor temperature of 30°C scored 20% lower on tests than those in classes around 20°C. In fact, the performance of adolescents appears to be more heat sensitive than the performance of adults in occupational settings. Added to this is the fact that many adolescents live in housing that is poorly resistant to heat. In informal settlements and some formal low-cost housing developments, for example, indoor temperatures may be 4 – 5°C warmer than outdoors – conditions hardly conducive to completing homework, preparing for examinations and quality sleep.

In classes with poor ventilation, levels of CO2 or stuffiness rise together with temperature, and children experience symptoms characteristic of the ‘sick buildings syndrome’. These symptoms affect concentration and student learning, and even school attendance and rates of asthma attacks. Window opening is a key means of removing heat and CO2. However, in towns and cities with high pollution levels, such as Witbank, one of the most polluted towns in the world, doing so would increase exposure to outdoor air pollution. Greenhouse gasses and other pollutants in themselves have substantial health consequences and are increasingly viewed as ‘secondary smoke’ exposures for children, no less harmful or unkind than smoking cigarettes in an adolescent’s bedroom.

There are major equity issues at stake here. Adolescents who have attended well-resourced schools with temperatures carefully controlled for optimal concentration will compete for jobs or places at university alongside those who wrote school-leaving examinations in temperatures above 40°C and were drowsy and probably poorly hydrated. It doesn’t help that key examinations are generally written in the summer months in South Africa.

Beyond the question of rising temperatures, climate change will increasingly affect water quality and availability at schools, with further implications for the health of children. Droughts may threaten water security in schools, dependent on boreholes or rivers for their water, while floods can contaminate water with infectious agents and toxins. Most water and foodborne infections, particularly those caused by bacteria, are heat sensitive. Bacteria thrive in warmer temperatures. Without adequate sanitation facilities in schools, close contact between school children makes the transmission of such infections all the more likely. Finally, high temperatures raise exposure to environmental toxins, which is worrying as many schools in South Africa are located near areas with high levels of toxic substances, such as major roads, mine dumps and industrial operations.

What can be done about this? Long-term initiatives to make the built environment more heat resistant are clearly critical, especially replacing containers and prefabricated buildings with properly ventilated brick classrooms. While the Department of Basic Education mentions environmental factors such as ventilation and the hazards of non-brick structures in its school infrastructure standards, these are yet to be fully addressed. Provision of safe water and sanitation in schools also remains an ongoing challenge.

But in the meantime, there are a number of cheap, simple interventions that could help to make hot classrooms more tolerable and reduce symptoms of heat stress. This means thinking beyond air conditioning, which is both expensive and unsustainable.

Possible interventions include the provision of cold water at regular intervals, and the application of damp cloths to the body, which cools as the water evaporates (a method once used by the ancient Egyptians). Schools could also consider substituting closed shoes with sandals, using light-coloured, loose clothing, and forgoing the wearing of blazers in the summer. Adapting school hours during the hottest seasons, is another possibility, with either earlier starting times or a longer lunchtime break and later finishing hours. Planting trees in schools would provide shade and cooling, and other health and environmental benefits. A ‘cooling room’ could be created in the school, where, for example, fans are installed on the walls, the roofs are painted white, plants are hung on the walls and trees are planted nearby. During extremely hot days, pupils could spend time in the cooling room during breaks or after school, and the room could be used for examinations.

Despite their relatively low cost, these interventions may be challenging to implement, however, and we need to anticipate scepticism among stakeholders. Many people view heat only as a nuisance factor or a ‘normal’ occurrence to be tolerated, rather than as a modifiable risk factor influencing health and learning. This perception needs to change. The holding of classes outdoors in shaded areas on hot days may be viewed by some as a symbol of failed school infrastructure in South Africa rather than as a heat-reducing measure. A supportive policy framework for heat-health interventions in schools, and a firm commitment from education and environment ministries will be important steps in laying the groundwork for action.

Aside from its obvious immediate benefits, climate change adaptation in schools may be an under-recognised but important strategy for countering inequities in South Africa. Young people in this country bravely took a stand against apartheid. For local youth activism against environmental destruction, there is still a long road ahead. Safeguarding schools against the health and education impacts of heat may just be a good place to start.