Utilities

<p>So, does the solution lie within the facility HVAC systems? In most cases no, for the simple reason that most buildings were engineered to provide general comfort and not to provide disease abatement. Education and conscious effort is key for prevention of COVID-19. The best practices regarding containment will remain with sanitation of surfaces, exercising judgement across the board, and plain common sense (Hand washing, avoid Handshaking, surface sanitation, use masks and social distancing). The best prevention still lies with good personal hygiene, sanitation, a conscientious effort to avoid public or private gathering if sick and to a minor degree, the facility systems. Coronavirus is still a developing story at the time of this writing, so I hope some general guidelines help in establishing priorities and strategy for engineers at Hotels or Hotels turned in hospitals or coronatine rooms/areas.</p><p>While above help but you still need people to operate and maintain your hotels/ facility. Digitization is the first step, not only can control contamination, but also can seek support from the best engineering resources available from team B/outside help. Make your facility connect remotely for monitoring, controls, and automation.</p><p>Let&rsquo;s understand, how much is the story unfolded for this virus till date, according to the WHO (World Health Organization), &ldquo;The COVID-19 virus spreads primarily through droplets of saliva or discharge from the nose when an infected person coughs or sneezes, etc.&rdquo; Talking and breathing can also release droplets and particles. Droplets generally fall to the ground or other surfaces in about 1 m (3 ft), while particles (aka aerosols), behave more like gas and can travel through the air for longer distances, where they can transmit to people and also settle on surfaces. The virus can be picked up by hands that touch contaminated surfaces (called fomite transmission) or be re-entrained into the air when disturbed on surfaces. However, if the droplet got a chance to evaporate, since the base of the droplet is water, then it would become droplet nuclei that might circulate in HVAC system. How to avoid/controls this circulation into air?</p><p>Any air cleaner that removes particles has some potential to get rid of coronavirus? Not sure it&rsquo;s true.</p><p>The question is, which filter is effective enough that it will have a significant impact on how likely people are to get affected by the airborne route?</p><p>Even HEPA filters that have been tested in the laboratory with viruses will have some level of penetration. Not much &mdash; 2 percent. But if anything gets through, and if it's a very virulent pathogen, that doesn't mean that you're perfectly protected against infection by that filter. Same thing with UV. There's UV susceptibility of coronaviruses ... it's maybe somewhat less than the net of influenza, but still susceptible. So, if you were treating contaminated air or contaminated surfaces with UV, can expect to reduce the concentration of coronavirus on it by some amount. It cannot be confirmed that HEPA filers or UV lamps disinfect COVID-19.&nbsp;</p><p>Some of the best practices can be applied if not all are below related to HVAC system to prevent or control this contamination:</p><p><strong>Ventilation</strong>: One thing that reduces risk is having 100 percent outside air system and Negative pressure in guest room shall help to prevent spreading outside to corridors/ common areas.</p><ul><li>Run 24x7 PAHU&nbsp;(Pre-cooled Air handling units) for thermal comfort</li><li>increase outdoor air ventilation by&nbsp;opening window&nbsp;if outside air quality is good</li><li>Disable&nbsp;demand-controlled ventilation (DCV)</li><li>Further&nbsp;open&nbsp;minimum outdoor/fresh air dampers, as high as&nbsp;100%, thus eliminating re-circulation of air</li><li>Negative pressure shall help to prevent spreading, 100% exhaust and run FCU/AHU at lower speed/VSD controls.</li></ul><p>&nbsp;</p><p><strong>Humidity</strong>: Increased/higher humidity may not let the droplet evaporate so less chances of circulating into HVAC System, this may help to prevent the droplet from drying out and floating freely in the air.</p><p>&nbsp;</p><p><strong>Air filtration:</strong>Although, it CANNOT be confirmed that HEPA filers or UV lamps disinfect COVID-19, however a good care to be taken to avoid contamination.</p><ul><li>Improve&nbsp;air filtration to the MERV-13 or the highest compatible with the filter rack, and seal edges of the filter&nbsp;to limit bypass.</li><li>If one doesn&rsquo;t have&nbsp;MERV 13 or better filter, please&nbsp;do not change filters at all, chocked filers are better to avoid small particulates, more its chocked, better it is for particulates reduction.</li><li>Keeping surfaces clean is also important, and there are plenty of UV devices around now that are used mainly in healthcare environments to disinfect surfaces during unoccupied periods. One of the things that been told by some people who've been doing it for years it keeps the coils pretty much like new. Use UV lights&nbsp;in return ducts if you can&rsquo;t avoid re-circulation of Air.</li></ul><p><strong>Some additional measures to do:</strong></p><ol><li>Create Isolation room in hotels: Use separate HEX and AHU for such areas with separate controls and automation</li><li>Use additional damper actuators to avoid re-circulation of air across different areas</li><li>Coronatine area to be negative pressure area, use automation and controls to create negative pascal, keep minimum 02 AC/H.</li><li>Don&rsquo;t switch of the area/ room&rsquo;s ventilation &amp; exhaust even if you need to switch off air-conditioning for hotel during shut down. Let&rsquo;s it run and disable the ventilation control.</li><li>Run boiler to produce hot water on secondary side above 50C+ to avoid infections.</li></ol><p>&nbsp;</p><p><strong>Some actionable during the facility shutdown (if no choice left):</strong></p><ul><li>Run the Condenser water through cooling tower to avoid formation of algae, molds/ fungi at least once a day for 4 hours or completely shut down the condenser system and drain the water from cooling tower.</li><li>Run Chilled water pumps for at least 02 hours in a week to ensure no formation of algae.</li><li>Run FCU and AHU fan at least once a day for 02 hours to create air changes.</li><li>Keep the ventilation and exhaust/ specially toilet exhaust fans On 24x7 with minimum 02 air changes per hour.</li><li>Keep the U-trap of AHU filled with water to avoid cross infections.</li><li>WC flush and urinals to be cleaned daily.</li><li>Run the Boiler for hot water above 50C+ at least once in 15 days with a water drain for 15 mins for both washbasin and shower.</li><li>Cover the bed sheets and mattress with vacuum plastic covers to avoid smells and moisture.</li><li>Fabric and carpet to be cleaned with hot air once in a week.</li></ul><p>Remote monitoring and retro commissioning (Air and water balancing) is required by an experienced team once you start back in business or recommissioning the system after COVID-19.</p><p>&nbsp;This document is by no means definitive or attempts to deal with all aspects of COVID-19 treats. As the situation is always evolving, this allows the hotel team to adopt measures to be better manage the health risk. Local Authorities and WHO directives will have to be followed where applicable.</p><p>Precautionary measures although not proven in its entirety to eliminate COVID-19, are still better than NO measures at all. I'm happy to connect and contribute my best to help the engineering community. Feel free to connect for more</p><p>&nbsp;</p>