During and after the pandemic we are going through, responsibility for the application of Indoor Air Quality standards will be fundamental.
By Eng. Gabriel Jiménez Álvarez*
The COVID-19 crisis will be for our HVAC guild what 9/11 was for security companies in terms of challenges and opportunities, with the mitigating factor that the impact of COVID-19 is practically all over our world.
Our level of opportunity goes hand in hand with our level of responsibility and preparation as a guild to meet indoor air quality standards and good practices (term known as CAI in Spanish and IAQ Indoor Air Quality in English) from the design, assembly, operation and maintenance of air conditioning systems in all applications, and even think beyond because the minimums that the current standards ask us will be in many cases insufficient in the face of the new reality, for this we need suitable professionals of the best qualities with the appropriate experience for each project, who have the criteria to implement solutions beyond the only normativity, in design, assembly and operation of the systems.
All of us who work in this market have had the opportunity to know the reality of many systems in hospital and commercial applications and it is regrettable to say that a good part of these systems do not meet the current cai standards or much less the new requirements for this new era; and in this as a guild we must make a mea culpa because we are responsible for action or omission, the permissiveness before poor practices in CAI will not be acceptable, it is also fair to say that many of the current shortcomings are the product of financial pressures where the CAI was sacrificed to maintain CAPEX or OPEX costs according to the situation of each project, lower levels of filtration, less outside air, not investing in air recuperators, insufficient spaces for proper equipment maintenance, etc., are some examples of these "savings" that sacrifice air quality.
These purely financial criteria also affect the CAI during the useful life of the systems, since it stops investing in adequate maintenance, in change of filters, in updating of obsolete equipment, etc. And what about the importance that traceability and monitoring of compliance with good practices for a minimum air quality will now take? Well, we all know that when the projects are delivered they are operating well, but after a few months the reality may be different. In my view, if the country and our region do well, the current and new IAC standards that emerge will become mandatory and monitored.
Many of us in our Latin American countries at some point have come across air systems that serve public places and even hospital systems with obvious flaws:
• Closed outdoor air intakes or total lack of these, pursuing an energy economy at the expense of indoor air quality and was something that was often allowed to pass, now it is clearer that these shortcomings put us all at risk, injecting outdoor air, as you know, is key to dilute pollutants, in hot weather this strategy is mistakenly used as a way to save energy. In climates such as Bogotá, applications also suffer from low air quality, as it is common that the systems are not designed for cold outdoor conditions and the great solution is to turn them off, or you have a bioclimatic solution that may be insufficient to the new reality.
• Condensate trays with permanently posed water, remember that the coils of our systems have the ideal condition in temperature, humidity and low light level for the growth of bacteria and fungi and to prolong the life of the viruses that arrive here, this is also a point to improve.
• Poor filtration levels and inadequate maintenance are common, lack of adequate filters, low frequency of change and even total absence of filters.
For those who do not know, the importance of a good level of filtration is now greater in this new era of viruses such as COVID-19 with long survival times in the air and on surfaces, because viruses, according to studies, do not survive alone and require to transport some micro particle in suspension such as a fomite or microdroplets of saliva.
Merv 14 Upward Filters are effective in trapping these means of transport and thus minimizing the risk. Current standards do not require in most applications leaks higher than Merv 8 which barely filters coarse dust, I consider that this will be one of the first changes to be implemented in public places, where a minimum Merv 14 filtration must be implemented, this in commercial applications is uncommon, some LEED projects have these levels because it gives points to recognize that they generate better air quality. This will have a cost that we must all assume directly or indirectly, the operating costs will rise, but not doing so will generate greater cases of contagion before any new airborne virus and in this case the cost will be in treatments and in some cases life. As always it is better to prevent than to cure.
Restaurants are also one of the guilds that must update their systems, an important requirement will be to separate the air from the table area from the air of the cooking area, and in both areas provide adequately filtered air. Currently in most restaurants the air of the table area reaches the preparation area by the suction generated by the extraction hoods; few restaurants have the well-known Make-Up systems that were originally created to prevent the hood from "stealing" the air conditioning in air-conditioned restaurants. Our new reality requires us that we now have an outdoor air injection system filtered into the kitchen area, separated from the system in the table area, because as we have already seen in different publications and on social networks, viruses such as COVID-19 airborne on micro droplets or particles for at least 10 minutes in the air or it can be longer, and various studies are being done on this.
Today, and for a long time we have various technologies and strategies to achieve the air quality in indoor environments that the new reality requires, this was previously a luxury of few projects and / or few industries but I consider it should become an imperative in any public place.
Technologies such as UV lamps in coils and photocatalysis purifiers should become mandatory in any air handler that serves a public place such as offices, supermarkets and obviously clinics and hospitals. Technologies such as photocatalysis that generate a plasma with natural particles and natural ecologies that clean the air become key, since they kill all kinds of viruses, bacteria and fungi including the entire family of coronaviruses, these not only act in the coil but in all the air that passes through these elements, which is known as active filtration, because it acts not only in the place where the purifying element or filter is; of this, various brands have begun to appear and it is key to use brands with the right support to achieve the expected results.
Schools and universities are also buildings where the application of CAI regulations will be key, currently many of these in hot earth have mini split equipment solutions, which only serve the thermal part but leave much to be desired in air quality, because to begin with there is no outdoor air management. We get used to the fact that when children enter the garden they will get sick, but this can no longer be normal; schools must implement systems that comply with CAI standards, and also have at least technologies such as purifiers by photocatalysis, and this actually applies to all spaces, restaurants, bars and nightclubs, offices, warehouses, or any place where we share the air we breathe requires this type of elements or other technologies or strategies that achieve the equivalent.
The universe of application of these recommendations is in practically every building we know. Where will it not be necessary to have a minimum CAI for activities of daily living? There is a lot of work that will be generated for our guild, but of the same size will be the responsibility for the result; we will be singled out tomorrow as heroes or villains.
Conclusions
We are facing a new world where all the places we previously attended unsuspectingly will have to generate confidence to return, just as the security systems and procedures at airports changed after 9/11, to get back on a plane with confidence ... so they must change our parameters for CAI, in order to re-enter the interior spaces we share.
But eyes that do not see heart that does not feel. Most users do not know what the air systems of a building are like, they hardly see the grids or the interior equipment. It is our responsibility to be the eyes in today's world so that the world has the sensitivity of the importance in the quality of air in indoor environments, we are a key part for the public to return with confidence to the different indoor environments; it is our duty to act as a guild and disseminate to our customers the good practices of CAI, invite them and help them update and improve their systems for the present and for the future; today as never it is evident how we are all connected: how to take care of the other is to take care of myself.
We have the great opportunity to make known to the world the importance of our systems for this new era, where the CAI will be an imperative, because just as airports changed forever after 9/11, our world will never be the same after Covid-19. Nor can our planet afford to stop again as is currently happening; we have the technologies and knowledge to generate safer indoor environments in the face of a new threat, which, combined with new rules of coexistence, will allow us to continue living a life similar to the one we had previously.
* Eng. Gabriel Jiménez Álvarez. Aciem escalafon 1. ASHRAE CHD HFDP HBDP. Founding partner of HVAC Consulting S.A.S.
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