June 4, 2024
SINGAPORE – As heatwaves around the world last longer and ultraviolet (UV) indices hit extreme levels, some schools in Asia have been forced to close for the well-being and safety of students and staff.
According to the Meteorological Service Singapore, the highest UV Index reading in Singapore in 2024 was recorded at 1.30pm on Feb 15. It measured 14, just one point away from the maximum level of 15 on the UV index.
In 2024, the highest daily temperature of 36.4 deg C was recorded at Paya Lebar on April 26.
In Singapore, the classrooms in most primary and secondary schools are not equipped with air-conditioners.
But some schools were not caught off-guard by the heatwave, as measures have been in place to help reduce the impact of soaring temperatures on staff and students.
Dri-fit polo tee second uniform in Beatty Secondary
Since 2020, Beatty Secondary School has had a second uniform for students comprising a polo tee made of a dri-fit material with moisture-wicking properties.
It is one of a few schools here to have an official second uniform that is more casual and comfortable to wear.
“The formal uniform is quite restrictive (of my) movement, and I can feel it sticking to my body when I perspire. Coupled with the tie, it can feel constricting in this hot weather,” said Secondary Two student Lucas Tan, adding that the hot weather makes him feel drowsy and tired in school.
When he is wearing the formal outfit, he is constantly perspiring, and “it’s very hard to stay focused during lessons”, he added.
He said that the polo tee material is more breathable and helps sweat to dry faster too.
Before the school allowed students to wear the school polo tee every day from April, students had to be in full uniform on Mondays. This meant wearing the school shirt and tie.
Mr Harman Johll, the school’s principal, said that after observing students and teachers during lessons, he wanted to help them manage the humidity and heat.
“It is important for us to try to understand what the classroom environment is like. The weather is getting warmer, and the polo tees allow for more thermal comfort,” he said.
Teachers in Beatty Secondary also have corporate polo tees made by the school, which were usually worn for school events. Now, amid the heatwave, they are also able to wear them for daily teaching.
The school’s senior teacher for English language, Ms Toh Ji Rong, said that compared to when she first started teaching 17 years ago, the weather these days is much warmer.
She finds the school’s polo tee comfortable to wear without it being too casual.
“As teachers, we need to project that professional image. So for those of us who aren’t PE (physical education) teachers, we can’t dress down to the extent of wearing T-shirts, but polo tees are more suitable,” she said.
Greenery and blower fans in Yu Neng Primary
In 2005, after almost three years of refurbishment works had been completed, Yu Neng Primary School in Bedok North had little greenery.
That year, the school embarked on a quest to turn its campus into a garden.
Its operations manager, Mr Lim Yew Chai, said that the school began the task of greening up the school with trees and plants that suited the school’s landscape.
While the school did not say how large an area its greenery covers, The Straits Times saw that most outdoor spaces that were not used for walkways or for play and exercise were converted into green spaces.
Among its variety of greenery, the school has a rubber tree, mango tree and a towering palm tree. Mr Lim said the school’s plants and trees were selected based on the ease of maintenance and how well they grew.
“Every tree has a purpose, and some of the trees have become iconic. Over time, they have become part of the school’s unique identity. When you come in and see our tall palm tree, there is a wow factor,” said Mr Lim.
He added that the greenery provides a lot of shade and areas for pupils to rest and refresh themselves.
“When they go to these green areas, it provides them with therapeutic refreshment of sorts.”
Head prefect Ashton Choo, 12, said he appreciates the school’s ample greenery and that it is part of the school’s identity.
“We have eco gardens where we can admire all the different plants and enjoy the cooling shade. It feels like the plants belong to the school. Without them, the school doesn’t feel normal,” he said.
Mr Ng Yeow Ling, who joined the school as principal in December 2020, said walking on the third level of the school feels like walking along a tree-top trail because of how close it is to the canopies of some trees.
“(With) hindsight, I saw the wisdom in making the school so green and nurturing this symbiotic relationship with nature so close to us,” said Mr Ng, adding that the greenery provides natural shade and helps to lower surrounding temperatures.
In parts of the school where nature’s cooling powers do not reach, technology steps in.
In 2015, a well-wisher donated 10 blower fans to the school. In recent years, they have been put to greater use because of rising temperatures – they are placed in areas such as the canteen, hall and walkways.
When ST visited the school in April, pupils were seen standing in front of the blower fans in the canteen to get instant relief from the humidity and heat during recess. Mr Lim told ST that the blower fans are able to circulate cool air and generate wind reaching up to a distance of 10m.
Ashton said that the blower fans are popular with his schoolmates – and himself, too.
“The air is very powerful and very cold, so it helps us to cool down very quickly. If I see no one there, I will usually stand in front of it for a short while to enjoy the fresh air,” he added.
Cool paint and sunshades in Tampines Secondary
Tampines Secondary School has been able to use cool paint, optimised ceiling fan placements, sunshades on windows, and ventilated chairs to help students and staff feel cooler and more comfortable.
In April 2018, the school was used as a pilot test bed for the Building and Construction Authority (BCA) to explore improving thermal comfort and energy efficiency in an existing building.
Testing was conducted in the school using two adjacent classrooms – a reference classroom which was left unchanged and a test classroom which implemented the innovations.
Cool paint, which reflects incoming solar radiation away from the surface, was applied to the roof of the test classroom. This resulted in a maximum reduction of 12 deg C in the roof surface temperature and an average reduction of 1.8 deg C in the indoor ceiling surface temperature.
Eight smart direct current (DC) motor fans were installed in a staggered fashion in the test classroom, compared with the six alternating current (AC) fans, positioned in a two-by-three grid in the reference classroom.
The optimised placement of the smart DC fans improved airflow speed at the front of the classroom, and distributed the air more evenly around the classroom.
Most windows at the school were fitted with rain diverter devices to prevent rain from entering classrooms. The rain diverter at the test classroom was modified into a perforated panel to act as a sunshade.
The sunshades led to interiors that were up to 1.2 deg C cooler in floor temperatures.
Ventilated chairs with small holes in the back rest were found to increase surface heat transfer by 37 per cent. Those placed in the test classroom kept students more comfortable as they improved ventilation and helped the wicking of moisture from students’ bodies.
Over eight weeks, the innovations were monitored for their effectiveness on thermal comfort and energy efficiency. The BCA, in collaboration with the Ministry of Education, published a report on its findings in 2018.
All the innovations trialled in 2018 have since been implemented in Tampines Secondary School.
According to the BCA report, results at the school demonstrated how thermal comfort could be enhanced without resorting to air-conditioning, which should be considered as a last resort.
Mr Cheong Tien Beng, vice-principal of the school, told ST that through these measures the school is able to promote an environment that is sustainable and environmentally friendly.
“These technologies not only help to enhance indoor thermal comfort for a conducive teaching and learning environment but also help to reduce the overall energy consumption,” he said.