Hong Kong’s property prices continue to soar, with many individuals working hard to achieve homeownership success. However, after completing renovations on their new residences, they discover the issue of excessive indoor formaldehyde levels.
There are various methods for formaldehyde removal, and in recent years, photocatalytic services have emerged in the market. While these services can effectively eliminate formaldehyde in ideal conditions, they also bring about negative effects on the environment and personal health.
Therefore, before opting for such services, it is crucial for individuals to assess the effectiveness and impacts of photocatalysis, enabling them to make informed consumer decisions.
Major Hidden Dangers of Photocatalytic Formaldehyde Removal
High Dependence on Ultraviolet Light
Photocatalytic formaldehyde removal, as the name implies, requires sufficient light (solar energy/ultraviolet light) to activate the catalyst surface, inducing chemical reactions to decompose formaldehyde and other harmful gases into harmless substances. However, its application effectiveness is significantly limited in environments with insufficient light. With Hong Kong’s towering skyscrapers blocking natural light, it remains uncertain whether it can function effectively in the absence of adequate light sources.
Limited Efficacy
Experts point out that although photocatalysts can decompose some volatile organic compounds, including formaldehyde, not all volatile organic compounds can be effectively decomposed. Additionally, photocatalysts require time to undergo chemical reactions and do not show immediate effects; continuous operation is necessary to maintain formaldehyde removal effects. Moreover, surface coatings may wear off due to friction, diminishing the formaldehyde removal efficiency, which is not permanent. In comparison to photocatalysts, indoor ventilation and methods like activated carbon show more significant and rapid results, unaffected by external environmental factors, making them more reliable formaldehyde removal methods.
Secondary Air Pollution
When using photocatalytic formaldehyde removal, it may lead to the generation of secondary pollutants such as formaldehyde acid, more toxic compounds formed after formaldehyde decomposition, posing greater threats to human health. For example, dust generated after spraying can cause respiratory sensitivity, itching, and other symptoms. Furthermore, if indoor air contains other pollutants like dust, dirt, nitrogen dioxide, benzene, etc., it might affect the efficacy of photocatalysts in formaldehyde removal and even lead to more severe air pollution issues.
Is Photocatalyst Effective for Formaldehyde Removal?
Many formaldehyde removal companies promote photocatalyst solutions, claiming that under light exposure, catalytic reactions can decompose harmful pollutants. Johnson Group’s General Manager, Mr. Keith Wong, explains:
“Photocatalysts rely on UV or visible light to generate reactive oxygen species that theoretically decompose formaldehyde. However, their actual performance depends heavily on light intensity, reaction rate, and environmental conditions. In indoor spaces with insufficient lighting or ongoing formaldehyde emissions, the real effectiveness is often below expectations.”
In addition, when the oxidation process is incomplete, photocatalytic reactions may generate by-products even more harmful than formaldehyde itself. Some products attempt to block VOC release by “sealing” surface pores on building materials — a temporary fix that wears off over time. Once the coating is damaged or peeled away, formaldehyde releases again, posing renewed health risks.
Recommended Methods for Effective Formaldehyde Removal
Apply SafePRO® Formaldehyde (VOC) Remover
Compared to photocatalysts, choosing natural non-toxic VOC materials is undoubtedly a more effective approach. Most conventional odour solutions consist of applying fragrances to mask the problem. SafePRO® Formaldehyde (VOC) & Odour Remover is a scientifically developed technology formulated specifically to eliminate unpleasant odours, without relying on strong perfumes and harsh chemicals.
Through triple-action technology (chemical neutralization, enzymatic decomposition, and surface absorption/sealing), it effectively breaks down formaldehyde molecules without relying on UV light, leaving a long-lasting protective layer. It is especially suitable for Hong Kong’s humid residential environments.
