Over the past few years, there was a rapid increase in the production and usage of Internet of Things (IoT) devices, which have flooded the computer, communication and consumer electronics (CCC) market today. IoT products and devices include laptops, smartphones, smart gadgets, smart watches, smart and digitalised vehicles, almost all of which are used extensively in our daily life, shaping the way we work, talk, and engage with each other. Undoubtfully, IoT devices have brought many advantages to mankind, not to mention improving our quality of life. Nevertheless, radiation hazards caused by these devices may still be a concern among the general public. This article presents the latest international safety standards on human exposure to electromagnetic wave and discusses how we can stay safe with IoT.
In 2020, Institute of Electrical and Electronics Engineers (IEEE) Standards Association published C95.1-2019/Cor 2-2020 - IEEE Standard for safety levels with respect to human exposure to electric, magnetic, and electromagnetic fields, 0 Hz to 300 GHz - Corrigenda 2. At the same time, the International Commission on Non-Ionization Radiation Protection (ICNIRP) published another set of guidelines for limiting exposure to electromagnetic fields (100 kHz - 300 GHz). Their purpose is crystal clear – Safety First, to lay down a concrete standard for adoption by CCC manufacturers before messy electronics could evolve. As compared to the previous standards and guidelines, the new version is providing a more accurate, detailed and better future-proof limits based on contemporary biological rationale and scientific researches on dosimetry. It documents the exposure limits of electric and magnetic fields, namely the strength of electric and magnetic fields, and power density for both the controlled (occupational) and uncontrolled (public) environment. As far as harmful implications are concerned, high electric field may give rise to the feeling of electric shock and induce pains; whilst high magnetic field could be absorbed by human body and lead to temperature rise in body cells, or adverse effect to body cells.
Though both limits exhibit a slight difference where the limit set by IEEE is more stringent than the ICNIRP limit in the low frequency region, it is advised that the limits from both standards should be adopted throughout the applicable frequency spectrum so as to identify the minimum exposure level that may cause harms. Hence, in case there is any doubt on high radiation from IoT device, the measurement of radiation exposure against the limits can be conducted with reference to IEEE C95.3. When any exposure to high radiation is anticipated, a hierarchy of controls should be applied to mitigate or reduce the possible exposure, e.g. reduce the power density, avoid being exposed to the radiation, minimise the duration of exposure, or simply select IoT that fulfils the aforementioned standards.
This article is contributed by Ir George Chan with the coordination of the Safety Specialist Committee.