Q1. IS ZAI BACKED BY ANY SCIENTIFIC EVIDENCE TO BE EFFECTIVE TO ELIMINATE CORONAVIRUSES?
ZAI is designed to replicate the dry heat conditions recommended in independent clinical studies , ,  to eliminate not just coronaviruses, but most bacteria and fungi. In , the authors investigated five disinfection methods; 1) dry heat disinfection, 2) alcohol spraying disinfection, 3) steamer wet heat disinfection, 4) high temperature and high-pressure disinfection and 5) ultraviolet disinfection, and they concluded the dry heat disinfection is most efficient and effective in both eliminating viruses as well as maintaining the filtering efficiency of the masks above 95%. The recommendation is to carry out dry heating at 70 degree Celsius or more for 30 minutes. For ZAI, we use a 45 minute duration to remove any doubt of under-sterilisation.
 Experimental research on safe and rapid regeneration of disposable medical masks, Journal of Microbiology and Infection online version, Fudan University Shanghai Medical College, February 9th 2020.
 Stability of SARS coronavirus in human specimens and environment and its sensitivity to heating and UV irradiation, Biomed Environ Sci, SARS Research Team, Institute for Viral Disease Control and Prevention, September 2003.
 Developing home-disinfection and filtration efficiency improvement methods for N95 respirators and surgical facial masks: stretching supplies and better protection during the ongoing COVID-19 pandemic, Journal of the International Society for Respiratory Protection, Columbia University, 37(1), 2020.
Q2. WHY IS ZAI NOT REGISTERED AS A MEDICAL DEVICE?
We choose to pitch ZAI as a lifestyle device designed for dry heating to produce the conditions recommended by clinical studies using a human safe electrical voltage. This is not a medical device as the components are already readily available commercially and have been used safely in the market. We want ZAI to be available to deal with the current COVID-19 pandemic.
Q3. WHAT ARE OTHER BENEFITS OF USING ZAI?
• ZAI allows for proper handling and storage of used masks.
• ZAI not only sanitizes up to two used masks concurrently, but can also dry the masks and make them more comfortable for use.
• The use of ZAI is simple and intuitive and it is powered by USB.
• ZAI is portable; it can be used on the go. It is low cost and durable; it is affordable and can be used for a long time.
• ZAI allows masks to be reused. This can mitigate the shortage of masks. With the drastic reduction in the disposal of masks, ZAI helps to make our environment more friendly.
• Apart from coronavirus, the heat treatment will also remove most bacteria and fungi.
Q4. IS ZAI SUITABLE FOR SOME N95 MASKS WHICH CANNOT BE FOLDED?
The isolation pouch of ZAI is available in different size. A bigger one can be used to put in a conical mask without having to fold it. However, the heating time is recommended to be set to 60M instead of 45M.
Q5. CAN ZAI BE CLEANED ROUTINELY?
Yes. The user can use wet wipes to clean all surfaces of the isolated pack and the heat mat. The heating element is carbon fiber and the heat mat (but not the USB connector) can even be washed if that is preferred.
Q6. HOW IS ZAI COMPARED TO A UV TREATMENT APPROACH?
ZAI uses a dry heating approach which renders it suitable to be used by the general public. Currently, use of UV-C light in the 260-285nm wavelength range must be restricted to controlled environments. Robots are used to sanitize empty rooms with UV-C as it is harmful to the eyes and skin of humans. UV equipment is also highly delicate and expensive, and require more research to achieve efficiency, cost, reliability and durability. UV-C treatment requires masks to be free from cosmetic, oil, food and other contaminants.
Q7. IS ZAI A LOCAL INVENTION?
Yes, ZAI is the brainchild of Dr Tan and Dr Lim. An Israeli team has reported a reusable N95 type of mask with a built-in heat sterilisation capability, further supporting the scientific basis that heat sterilisation is effective in sterilising masks.
Q8. I HAVE THE WASHABLE CLOTH MASK. DO I NEED ZAI?
Yes, ZAI can help to dry and sanitize the cloth mask too, so you can use it instead of washing your cloth mask. This is useful especially when you are on the go. Do note that cloth masks (woven masks) are not the same as non-woven masks (surgical and N95 masks) in terms of filtering efficiency. You should wear non-woven masks (if possible) if you will be in contact with high number of people, or if you work at the frontline. See reference *
* A cluster randomised trial of cloth masks compared with medical masks in healthcare workers, ncbi.nlm.nih.gov, 5(4), 2015.
Q9. DO I NEED TO BRING THE FULL ZAI PACK AROUND WITH ME?
Our recommendation is that you can leave the filament of ZAI (heat pad and USB timer) where your charger or powerbank is. You only need to bring along the aluminium foil bubble insulated pouch with you for mask storage over the day. For example, it is much better to keep your mask in the pouch while you are eating rather than leaving it on the table or stuffing it into your pocket which are not good practices to stop the transmission of coronaviruses.