Why is indoor air quality so essential for our health!

Talking with Thermal Control Business Update, Ketan Sheth, Product Manager – Air side products & Sensors, Belimo Automation India Pvt. Ltd., mentions that energy optimisation and a good combination of IAQ is a must for all the buildings.

 

Healthy indoor air is vital for the safety and comfort of human beings and healthy buildings. At Belimo Automation, we took a survey to enquire about the fundamental aspects in the context of indoor air quality. We also reached out to credible institutes, consulting engineers, auditors and some researchers. The findings indicated nine foundations for a healthy building. Based on the nine foundations, we arrived at the seven significant parameters in a building to take care of healthy indoor air. From the viewpoint of indoor air quality, safety and security are important parameters. It was Covid which reflected upon the importance of safety and security in the health plan.

 

Other vital parameters involve IAQ measurement and monitoring of HVAC systems. From a control point of view, visibility and monitoring IAQ is necessary to measure the precise amount of air exchange needed to deal with contaminated air. This involves a fair amount of air dilution to combat contaminated air and to strategise the airflow pattern.

 

IoT parameters 

When we talk about the IoT, the parameters which need to be analysed are temperature and relative humidity. The recommended average relative humidity for your indoors is 40 to 60 per cent. There is a persistent link between indoor air humidity, perceived IAQ, and associated health effects. The CO2 and other VOCs are also polluting the air. It is of paramount importance to maintain temperature and humidity, which constitutes an important aspect. Other things that need to be considered are restricting the spread of the virus, proper filtration and conditioning of the outside air before air exchange to prevent contamination. The freshness of the air CO2 level in the atmosphere has to be diluted, increasing production efficiency.

 

Many studies have found that when the humidity is between 40 to 60 per cent, it reduces the risk of virus transmission. Hence, humidity is a major constraint in the spread of the virus. Hence, the visibility of parameters is of significant value regarding the awareness of IAQ. In this context, making the IAQ level visible to the people is pertinent. This would increase the awareness level.

 

To this effect, Belimo can contribute quite reasonably as it has an excellent range of sensors in terms of measuring temperature, relative humidity, CO2 in the duct, and the measurement that can be displayed in the rooms by the sensors. Even the accuracy of sensors and deviation in it can be checked out. While talking about the IoT’s seamless integration with any automation system, BMS or the PLC automation system can depict performance values. These can be ascribed directly to the cloud platform for analysis and monitoring of the controls.

 

The second aspect is that contaminated air must be removed. Adequate airflow as per the design based on the number of occupancies is a must. This helps in regulating the precise amount of air needed in the zone which contains contaminated air. Here, CFM (Cubic feet per minute) and the number of ACH (Air Change per hour) for air ventilation need to be measured to achieve better control.

Consequently, contaminated air should be diluted, as the higher the concentration, the longer the duration of the contaminated air in the room. To deal with such issues, a major solution that Belimo can contribute is the VAV solution. Also, for accurate temperature, relative humidity and CO2 measurement, there is a fan optimiser, which is also effective for energy saving. If IAQ is necessary, then energy efficiency is also essential.

 

A good combination of IAQ and energy optimisation is necessary for all buildings. Other essential aspects incident to it are proper air dilution and the airflow patterns. Airflow in each room should be carefully designed and adjusted because – most of the time, either there is a lack of CFM or more of a CFM, so it needs to be adequately controlled. Under-floor air distribution is also an excellent way to maintain airflow in the room. But in Indian situations, we work primarily in overhead areas, using diffusion efficiency of the duct air. The efficiency of the diffuser also depends on the accuracy of controls.

 

Demand control ventilation 

Generally, the designs are always created considering the buildings always have more pressure than outside pressure. The measurement requires a high-pressure measurement and quick control on that. It results in better and more precise control of room pressure. As soon as there is a pressure drop, there is a heightened sense of virus spread. So, pressure control in areas is crucial. Here comes the role of the VAV solution for the demand control ventilation with cascade control. One can observe the supply with a highly accurate sensor which helps achieve precise room pressure control.Yet, one of the more important aspects is the rapid response time from the actuator to maintain the required amount of air inside the room to achieve that required pressure. There are fast-acting actuators, which act within two seconds, four seconds, or seven seconds to reach the amount of pressure. Hundreds of thousands of buildings worldwide incorporate Belimo actuators into their HVAC systems. Belimo damper actuators are designed for various HVAC applications, ensuring performance, reliability and lower power consumption. When the humidity is between 40 to 60 per cent, the virus is less likely to spread in that range. 

 

Similarly, the temperature between 20 to 24 degrees Celsius is highly safe and healthy; it does not promote or does not support the spread of virus transmission. The right combination of good humidification and low energy consumption must be found, which should be integrated into the design criteria. However, proper maintenance is also one of the biggest tasks, which is very important for maintaining the hygiene of the humidifier and the rest of the air conditioning system. We must always start with an accurate measurement of temperature, relative humidity and the dew points in the room.

 

Filter selection

 The filter selection is very important based on the application and specific arrangement. The filter plays a vital role, and MERV13, MERV8 and other such technologies assumed importance after Covid came into the picture. The UV objects that obstruct the virus’s spread are also installed in the ducts. The return air filters are also crucial from the point of absorption of the contamination. Moreover, the filter maintenance should also be based on the usage, accounting for the dust accumulating. The automatic filter logs for maintenance replacement are essential. Of course, there are other ways to monitor filter clogging, such as dynamic filter monitoring. Filter banks or sensors are also available for communication and monitoring in terms of raising the alarm and using the technology from the BMS point of view.

Conclusively, the air may be contaminated, so we need to treat it specifically regarding CO2 levels by bringing in outside air to dilute the CO2. The ventilation standard codes have to be strictly followed. Consequently, it should not be compromised at the cost of energy efficiency. The solution is the thermal management solutions, quality of air from generation to distribution till the final delivery, and precise control of the zone using VAV solutions. The IoT and reliable sensors help achieve reasonable control to arrive at the solutions. Investing in new technology is the key to success. We must adhere to this as a global initiative in terms of essential parameters of healthy indoor air.