VietNamNet Bridge – A handmade cooling device – one of the best selling products for low-income earners in cities can cause negative impacts on users’ health and household appliances, engineers and health experts warns.

Cheap but unsafe: A student demonstrates a handmade cooling device designed to cope with summer heat. -- Photo thanhnien.vn

The handmade cooling devices became popular in big cities like HCM City and Ha Noi last summer when Duong Ngoc My, a senior student studying automobiles at the Ha Noi University of Industry, developed the invention to cope with rising temperatures.

The device comprises a mini fan, a 60ml water bottle, a piece of foam and uses a USB connection for power.

From a 62sq.cm rectangular box, My makes an air conditioner equivalent to 2000BTU. A regular air conditioner sold on the market ranges from between 9,000 to 12,000BTU. Two kilos of ice (VND6,000 or $0.27) is enough to produce cool air for a 10sq.m room for four or five hours. In practice, this can reduce room temperature by around six or seven degrees Celsius.

Following My’s example, people rushed to make similar “air-conditioners” at home or buy them at prices ranging from VND100,000 ($4.50) to VND400,000 ($18.00).

In HCM City, citizens have been using a styrofoam box, mini fan and L-shaped waterpipe to make a similar air cooling device. Such devices can cost between VND200,000 ($9.00) and VND450,000 ($20.00) to manufacture.

Dr Tran Van Thinh from Ha Noi University of Science and Technology told Khoa hoc và Doi song (Science and Life) newspaper that handmade cooling devices are simple to make but could pose risks to the user’s health.

The device works on a similar principal to that of steam fans, which were popular for years, he said.

However, when using handmade cooling devices, users cannot adjust the temperature.

More importantly, Thinh said the ice-run devices have the potential to spread viruses and bacteria if the frozen water used is contaminated. Viruses and bacteria are major contributers to summer diseases, particularly among young children.

He added that uncontrolled humidity released from the devices could also damage electrical equipment and circuits.

However, students and low-income earners who have been quick to adopt the handmade cooling devices said that they were satisfied with their devices.

At least, they helped relieve summer heat which is so often the bane of many city-dwellers’ lives.

VNS