Eco Office | Livecast Review on Indoor Air Security


During the lunch break on April 8, Shanghai Roots & Shoots invited two guests to answer the question regarding the use of air-conditioners asked by those office workers who have returned to work or about to return. These two guests are Mr. Qian Yingchu (Founder of Harvency Building Commissioning; Guest tutor of Tongji University) and Mr. Sam Michael (Executive Director, AtmosAir Asia).

Under the context that the topic of Covid-19 prevention keeping closely related to every individual’s health, folks remain uncertain about the usage and disinfection of air-conditioners. Such as…

Question 1: Does “no use of air conditioner” really mean safety?

Qian: Indeed, the government had issued a guideline about epidemic prevention in public places, which discourages people from using air conditioners. Well, if you do want to use air conditioners, you would have to use the fresh air system by which the indoor and outdoor air can be exchanged and the outdoor air would contribute to dilute the foul air. Besides, we need to be flexible in thinking about this question. For example, air conditioners are relied upon by the windowless rooms located very inside of a building to refresh the air.

Sam: At present, it is feasible to control the operation of air conditioners well. And you don’t turn off air conditioners in summer, because you cannot work in a building without cooling systems.

Question 2: Whether the air conditioning system and the fresh air system are the same system?

Qian: Plainly speaking, the fresh air from outside is processed by the air conditioner before coming inside and any contaminants within it are filtered. This means the fresh air system is an integral part of the central air-conditioning system. The fresh air system and the core part of the air conditioners are closely integrated.

Sam: The fresh air helps to dilute indoor air pollutants. Therefore, people are supposed to use the fresh air system reasonably, rather than keep closing it for “energy conservation”.

Question 3: Whether the cleaning and thorough disinfection of the pipeline and the vent can ensure safety?

Qian: Although the cleaning team’s cleaning and disinfection work for the air-conditioning system is essential during the Covid-19 crisis, office workers also need to be familiar with their offices’ air conditioners per se. How about the effectiveness of cleaning? Of course, we would advise the lessee to invite professional teams for inspections. The sensor used for monitoring air quality can be installed on the internet of the property management’s intelligent system, enabling the lessee to know the air quality at any time.

Sam: The virus can also be spread easily by virtue of sneeze or cough during interpersonal contact, which indicates little relevance to the condition of the pipeline. One breathes about 6,000 liters of air per day in an office. Hence, the source of the air we breathe is what we need to concern with, just as important as the source of the water we drink or the food we eat. We can learn more about air filtration and fresh air system by consulting the property management team.

Qian: Yes, only the concern from the demand-side could drive the change of the supply-side.

Question 4: Is it safe to open the window when using the toilet? Can feces spread the virus?

Qian: We would advise not to open the toilet’s window if it can be opened. This is not only out of the concern of privacy protection but also because the opening of windows will impact the operation of the whole building’s fresh air system. Normally, the virus will be washed away by the water closet thanks to atmospheric pressure. However, opening the window will sabotage the system result in the spread of the virus into other parts of the building.

Sam: The fresh air system plays a protective role in the toilet, while the opening of windows will disturb the operation of the system.

During the live cast, we also learned that the high concentration of CO2 will affect the efficiency of office work. The stuffy, uncomfortable, or ablush feelings are probably all derived from the concentration of CO2 in office. With regard to the temperature of air conditioners, 24-26 centigrade in summer and 18-30 centigrade in winter are optimal for energy conservation and comfortableness.

We also need to refer to relevant indexes to decide whether the windows and the fresh air system should be opened for improving the indoor air quality. For instance, the air quality of Shanghai is bad in winter, thus the opening of the windows is not recommended. PM 2.5 index denotes the outdoor air quality, which can be referred to. If the index is lower than 12, the windows can be opened.

Admittedly, we are supposed to be concerned with the virus due to the Covid-19 pandemic. The significance of air quality cannot be forgotten in the meantime. For individuals, the mask that can not only filter particulate matter but also protect the wearer against the virus. It provides dual-protection.

Shanghai Roots & Shoots started the Eco Office Program in 2006, providing a new method of environmental education as well as helping offices to find some effective and easy ways to reduce waste and lower their carbon footprint. By conducting Eco Office audits, suggesting environmentally-friendly habits in the office, and using data-driven scientific processes to identify challenges and find solutions, we help employees to raise their level of environmental awareness, reducing operating costs and environmental impact from the ground up.

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