Eurovent to host AHU webinar
BRUSSELS, DUBAI, PARIS, 14 April 2022: Eurovent, Eurovent Middle East and Eurovent Certita Certification announced they would be jointly hosting a webinar to discuss the energy efficiency of air-handling units (AHUs) in hot and humid conditions on April 28.
Making the announcement through a Press release, the three organisations said that as a crucial part of a cooling and ventilation system, AHUs can be built to a multitude of customer specifications and operating environments. Since January 2022, Eurovent has mandated its certified manufacturers to disclose the energy ratings for hot and humid climates when the products are sold in such environments, the three organisations said.
In reaction to mounting requests to adjust energy ratings to local climates, Eurovent and its certification body, Eurovent Certita Certification have developed an energy rating for hot and humid conditions, they said. Aside from such ratings for chillers and VRF systems, the use of a separate energy label for AHUs that operate in such climates requires a deeper look to understand implications and underlying operating principles, they said.
The aim of the webinar is to provide the technical background and an overview of the new energy label. It will feature the following…
- Eurovent’s energy label for hot and humid climates: Programme origin and methodology
- Energy efficiency in hot and humid conditions: Expert assessment and analysis
- Technical panel discussion
According to the three organisations, the webinar will conclude with a dedicated Q&A session, where participants are invited to discuss any issues related to the topics. Those wishing to attend, they said, may register via this link. Registration is free, they said, adding that the event will take place from 10am to 11.30am (Abu Dhabi time).
STULZ, Mirus, ebm-papst to host webinar on harmonic mitigation in data centres
FREDERICK, Maryland, 26 September 2021: STULZ, Mirus International and ebm-papst will be conducting part 2 of a e-discussion on harmonic mitigation in data centres, STULZ said through a Press release. The webinar is on September 28, the company added.
To improve energy efficiencies in today’s modern custom air handlers, highly efficient electronically commutated (EC) fans are often incorporated for air movement, STULZ said. This is because the fan systems can improve efficiencies over conventional AC motors equipped with variable frequency drives (VFDs) by 30% or more, it said. An EC fan incorporates a brushless DC permanent magnet motor (BLDC) controlled by an integrated rectifier, inverter and smart electronics.
BLDC motors, with efficiencies greater than 90%, provide a more effective ventilation system, so that ‘free cooling’ becomes more easily achievable, which contributes to the energy savings potential, it said. Also, air distribution can be improved with multiple fan arrays allowing upstream or downstream components, such as filters or heat exchangers, to receive a more even airflow, thereby improving air filtering and heat transfer efficiency, it added.
In striving towards reliable and efficient systems, one significant factor sometimes overlooked is electrical harmonic distortion, STULZ said. One of the few things common with AC/VSD and EC fan systems is that they are both harmonic generating, non-linear loads, it said.
Without proper harmonic mitigation, non-linear loads can distort the AC power distribution and possibly expose a mission-critical facility to electrical issues, such as overheating distribution equipment and failure of sensitive equipment connected to the same electrical bus, it added.
The speakers include Dave Meadows, Director of Technology, STULZ USA; Tony Hoevenaars, President and CEO, Mirus International; and Joe Landrette, Director, VAC & Data Centers and Digital Solutions, ebm-papst. According to STULZ, the webinar, scheduled for a 2pm (Eastern Time, US and Canada) start, will be useful to electrical engineers, mechanical engineers and end-users.
Dunli launches B-Max backward-curved centrifugal fan
Hangzhou, Zhejiang, China, 27 July, 2021: Dunli has launched the B-Max backward-curved centrifugal fan, which the company said is developed for high-end HVAC unit applications. Making the announcement through a Press release, the company added that the impeller, motor and controller of the fan were designed afresh to bring customers a better experience.
Describing the characteristics of the fan, Dunli said it:
- Is a one-piece solution, where the motor, impeller, inlet ring, supporting rack and mounting plate are matched and assembled perfectly into one piece. This feature, it added, enables ease of assembly for the customer.
- Has excellent efficiency, including industry-leading static pressure efficiency, which meets ErP2020 Standard requirements; an aerodynamic efficiency as high as 75% and above; and EC motor efficiency that meets IE4 standard.
- Has an optimised aerodynamic airfoil-shaped blade design through using CFD technology; and industry-leading noise level. These two features, it added, are the outcome of 40+ reliability tests that were performed.
- Has various control functions, including 0-10VDC (15VDC)/PWM signal control; phase-missing, over-current, over-voltage, over-temperature protections and signal control and fault alarm functions; and 485 communication function with MODBUS-RTU interface to monitor working, stop, speed and malfunction of the motor status.
- Has wide range of applications, wherein it can be widely used in AHUs, data centres and precision air conditioning
Eurovent announces granting first certificate for fans
PARIS, France, 2 July 2021: Eurovent issued its first ever certificate of the Eurovent Certified Performance programme for Fans, the body said through a Press release. Eurovent added that the certificate went out to direct-driven centrifugal fans using EC motor technology.
According to Eurovent, the scope of the certification programme includes all fan types that are intended to be used as air-handling unit (AHU) components. The certification programme is based on factory audits, software/DLL checking, random product sampling and tests according to ISO 5801:2017 for aerodynamic performances and ISO 13347-2:2004 for acoustic performances, Eurovent said, adding that all tests are performed by independent testing laboratories.
According to Eurovent, the following performances are certified:
- Static pressure difference
- Motor electrical input power
- Drive/control input power
- Overall (static) efficiency
- Inlet and outlet sound power levels
Systemair announces supplying smart, sustainable HVAC solutions for Expo 2020
DUBAI, UAE, 11 October 2021: The Systemair Group, as official sponsor of the Swedish Pavilion at Expo 2020, from October 1 to March 31 in Dubai, will showcase modern climate solutions from Systemair and Frico that, it said, will ensure visitors to the Pavilion are able to breathe clean air and enjoy the cool climate in a smart and sustainable manner. Announcing this through a Press release, Systemair Group added that Systemair and Frico will also be organising several exciting events aimed at educating stakeholders on the importance of achieving optimum indoor air quality without compromising on energy efficiency.
Morten Schmelzer, Technical Marketing Director, Systemair Group, said: “As proud sponsors of the Swedish Pavilion, we want to ensure visitors can benefit from healthy and comfortable indoor climate. Keeping this in mind, we have carefully selected the products that will ensure fresh air supply, which is especially crucial in view of COVID-19. Our solution also offers a minimum of 50% lower electrical power consumption and sustainable cooling recovery as high as 65%, which is unique for the Middle East. Lastly, the products are in line with the latest high European and ISO standards, which enable the best possible IAQ with minimum energy utilisation.”
Systemair Group said it supplied 10 of its high-end Geniox AHUs with state-of-the-art control systems to meet requirements of the local ambient conditions, as well as the spatial challenges posed by the unique design of the structure. It said it also supplied a sorption cooling recovery system with special material on the heat-recovery wheel, along with fan-coil units, a Sysaqua 170 chiller and a roof fan – the DVG EC560. The pavilion features two of the latest-generation air curtains from Frico, installed in the shop and the cafeteria, it added.
According to Systemair Group, Systemair and Frico will hold a VIP keynote event and reception night during the Expo, featuring leading global experts, who will discuss trends and innovations relating to the next generation of sustainable HVAC technologies. Also in the information dissemination mix, Systemair Group said, is an exclusive workshop that will elaborate on how stakeholders can leverage advanced technical solutions to obtain healthy indoor air in their projects while saving energy in their projects.
Carel launches pCOe
BRUGINE, Padua, Italy, 22 April 2021: Carel said it has widened its range of I/O expansions in the first part of 2021 with the development of a new digital input expansion board. I/O expansions are modules that can be added to a typical air conditioning application, to increase the number of inputs and outputs available on the controller and, consequently, optimise the flexibility and modularity of the solutions, the company explained through a Press release for the purpose of making the announcement of the launch.
Carel said one of the most common uses of the digital input expansion board involves ventilation sections comprising several fans with electronic motors; in this case, the speed of the individual devices needs to be monitored in order to check their operating status and act on the other fans accordingly, if one of them fails. Carel said it has for many years now offered all of the tools needed to support large systems, such as air-handling units or dry coolers, in which the fans are equipped with electronics that communicate via Modbus®, making it possible to directly monitor their operating status.
However, units that are smaller in size and capacity have simpler and more economical fans that do not feature serial communication and provide a pulse signal based on the rotation speed, which can be read by fast digital inputs, Carel said. This is the basis for the development of its new digital input expansion board, which the company described as an ideal solution for all cases where numerous digital inputs – including fast inputs up to 500 Hz – need to be read, however, while limiting the total number of I/Os and space required, adding only those that are needed.
One typical example involves so-called “in row units” used for cooling data centres. The highly compact units do not require complex device control architecture or specific sensors for their operation, Carel said. These feature a single ventilation section with at least eight fans in parallel, which need to be monitored individually. In this case, reading the signal is a simple and effective way to verify operation, as well as being a more economical solution than installing expensive air flow-rate sensors, Carel said.
The new expansion board, Carel said, features a high number of digital inputs to ensure maximum flexibility in different applications. This is essential on units where the main controller features a limited number of inputs and outputs, while multiple digital inputs need to be connected, for example to detect alarms or various signals.
The entire range of I/O expansions, Carel said, can be integrated into solutions based on the CAREL pCO and c.pCO programmable controller platforms, or into architecture using different controllers.
ASHRAE Epidemic Task Force releases updated Building Readiness Guide
ATLANTA, Georgia, 02 February 2021: With the performance of many HVAC systems in buildings still being evaluated, the ASHRAE Epidemic Task Force has updated its reopening guidance for HVAC systems to help mitigate the transmission of SARS-CoV-2, ASHRAE said through a Press release.
“The Building Readiness Guide includes additional information and clarifications to assist designers and commissioning providers in performing pre- or post-occupancy flush calculations to reduce the time and energy to clear spaces of contaminants between occupancy periods,” said Wade Conlan, Lead, ASHRAE Epidemic Task Force Building Readiness team. “New information includes the theory behind the use of equivalent outdoor air supply, method for calculating the performance of filters and air cleaners in series, and filter droplet nuclei efficiency that help evaluate the systems’ ability to flush the building.”
According to ASHRAE, major updates to the building readiness guidance include the following:
- Pre- or post-flushing strategy methodology: The strategy has been updated to include the use of filter droplet nuclei efficiency, which is the overall efficiency of filter, based on viable virus particle sizes in the air, to assist in determining the impact of the filter on the recirculated air on the equivalent outdoor air. This allows the filter efficiency as a function of particle size, using ASHRAE Standard 52.2 test results, to be estimated based on the expected size distribution of virus-containing particles in the air. This calculation is currently based on Influenza A data and will be updated as peer-reviewed research becomes available for the distribution of particle sizes that contain a viable SARS-CoV-2 virus. Additionally, a chart has been added to help determine the time to achieve 90%, 95% or 99% contaminant reduction, if the equivalent outdoor air changes per hour is known.
- Flushing time calculator: There is now a link to a view-only Google Sheet that can be downloaded for use, to help determine the available equivalent outdoor air changes and time to perform the flush. This sheet is based on a typical mixed AHU with filters, cooling coil, with potential for in-AHU air cleaner (UVC is noted in the example), and in-room air cleaning devices. Provided efficiencies of MERV-rated filters are based on the performance of over 200 actual filters from MERV 4 through 16, but the tool also allows users to enter custom characteristics for specific filters.
- The sheet also calculates the filter droplet nuclei efficiency, based on the cited research but allows a user to adjust the anticipated distribution of virus, as desired. It also allows specification of the zone (room) air distribution effectiveness from ASHRAE Standard 62.1 to account for the impact of the HVAC system air delivery method on the degree of mixing. Default calculations assume perfect mixing. Finally, the tool allows for the target air changes to be adjusted if an owner wants to achieve a different per cent removal in lieu of the recommended 95%.
- Heating season guidance: The guide now includes data to consider for heating of outdoor air and the potential impact on pre-heat coils in systems.
- Adjustments to align with Core Recommendations: The Core Recommendations were released in January 2021, and this guidance document needed to be updated to ensure that the information provided aligned with the intent of those recommendations. This included minimum outdoor air supply and filter efficiency requirements and their role in an equivalent outdoor air supply-based risk mitigation strategy.
According to ASHRAE, the guidance still addresses the tactical commissioning and systems analysis needed to develop a Building Readiness Plan, increased filtration, air cleaning strategies, domestic and plumbing water systems, and overall improvements to a system’s ability to mitigate virus transmission.
Building for the “new normal”
As the world continues to grapple with an ever-shifting economic landscape, owing to the COVID-19 pandemic, stakeholders in the building sector across the GCC region have observed how the pandemic has triggered an evaluation and reassessment of priorities. Ashok Jha, Head FM and Retrofit Projects, Universal Voltas, points out that the unprecedented disruption caused by COVID-19 has prompted many organisations to take actions they have been putting off for some time, including launching new digital services and evolving their business models, enabling greater flexibility in their working and implementing cost optimisation measures.
However, Jha says, perhaps the most notable trend would be the move towards a greater number of retrofit projects in the region. “Because of the COVID-19 pandemic, the oil prices plummeted to one of the lowest levels and government revenues went down in the GCC region,” he says. “This has led to reduced spending across all sectors, including new construction, with the current market seeing greater push towards shallow retrofitting, deep retrofitting, energy conservation and reducing the building carbon footprint in the existing buildings to make them more sustainable.” Jha says that since the number of existing buildings in Oman, Kuwait and the UAE is very high compared to new buildings, there was also a need to address the physical deterioration of the buildings, due to functional and economic obsolescence, and to make them more sustainable. “Because of this, there is a surge in demand for the retrofitting of the existing buildings across the GCC region,” he says (see sidebar).
Andrea Di Gregorio, Executive Director, Reem, Ras Al Khaimah Municipality, also believes the region is poised to see a strong pipeline of retrofit projects. “More focus is being put in refurbishing existing buildings, to bring them up-to-speed with the latest best practices in sustainability,” he says. “We see an increase in interest from building owners in retrofit activities, and we expect this interest to further increase throughout 2021 and in the coming years.”
Energy efficiency and sustainability
Another major driver for retrofits is the move towards energy efficient and sustainable practices, which has long been heralded by experts in the sector. Jha points out that because of the detrimental impact of buildings on the environment, with occupied buildings and the construction sector accounting for 36% of the global energy consumption and nearly 40% of total direct and indirect CO2 emissions according to International Energy Agency (IEA), the UAE has begun to actively transition into smart and sustainable cities, which has turned the focus on the energy efficiency of the buildings, specifically existing ones.
In addition to its impact on overall sustainability efforts, much of the move can be attributed to growing awareness on return of investment in terms of reduced operational cost. As Jha points out, retrofitting primarily refers to the measures being taken to replace legacy energy and utility systems with new and energy-efficient technologies. “These technologies not only reduce energy consumption and decrease carbon emissions but also lower maintenance costs, improve safety, enhance productivity, boost property valuations and also prolong the useful life of the assets and the building as a whole,” he says. “In a nutshell, we can say that OPEX of the building reduces and the asset value increases. Hence, it is becoming important day by day to retrofit buildings to not only make them more sustainable for the future but also to derive economical value by reducing the operational cost and, in turn, optimise the rentals and make them more lucrative for the tenants.”
Weighing in, Di Gregorio says that sustainable buildings often result in lower life cycle cost of the building itself. “If sustainability features are carefully selected, operational savings – in terms of energy and water usage and equipment maintenance – typically exceed any incremental investments that those features require,” he says. “For this reason, in a perfect market, where developers are able to fairly monetise their investments in higher quality buildings, we would expect for tenants any rent premiums for more sustainable buildings to be exceeded by the value of operational savings.”
Jha adds that as energy prices continue to rise, the relative benefits of energy efficiency will become increasingly important, and this is leading to a huge surge in demand for equipment, such as Smart LED lights and motion sensors, air curtains and FAHUs, energy-efficient AHUs, FCUs or split units and VAV systems. This has also led to greater demand for water usage reduction through the use of low-flow fixtures, sensors, waterless urinals and low-flush WCs, and also for photovoltaic panels on rooftops to generate electricity from the solar power, among other solutions.
A renewed focus on IAQ
While the return on investment (ROI) from retrofitting for energy efficiency is becoming clear, stakeholders are hopeful that the new wave of retrofits would also accommodate enhancements of indoor air quality (IAQ), which has been typically overlooked over the past years. Di Gregorio says that he believes this would be the case. “There is increasing interest in IAQ, partly driven by COVID-19 concerns,” he says. “Some awareness and technical barriers are there; nonetheless we foresee development in this area in the future.”
Jha shares a similar opinion. He says: “Fear of pandemic is looming large in the minds of the people, and therefore, while carrying out the retrofitting of their buildings, owners are ensuring that retrofit projects also take into consideration IAQ of the buildings, where people are currently spending more than 90% of their time and also to reduce the chances of contamination through virus, bacteria, moulds and fungi.”
Di Gregorio says there is a lot of focus on safety and security from building owners, particularly in what concerns disinfection of common areas. “This sometimes adds to other measures, like filtration, turning into improved air quality,” he says. Jha adds that some of the measures that building owners are taking include Demand Control Ventilation through C02 sensors, fitting volume control dampers, ultraviolet lamps in AHUs, ultraviolet germicide irradiation and MERV 13/14 filters. He further adds that there has been an increase in the use of humidifiers and dehumidifiers to maintain humidity in the range of 40-60%, where the microbial and fungal growth is minimal.
Jha also says that the majority of the offices are allowing their staff to work from home and that people are spending more than 90% of their time indoors. “This further necessitates that apt measures are taken by the occupants to ensure proper lux levels, ergonomics and IAQ, as these will have a profound impact on their health and wellbeing and, in turn, impact their productivity,” he says. “Hence, there cannot be a better time than now to address the Indoor Environment Quality (IEQ) issues, if any.” Jha says these are the factors driving a lot of investment being done by the property owners in the built-environment to retrofit their buildings to ensure proper IAQ against the traditional retrofit, where emphasis was mainly towards energy efficiency.
Making a case for retrofits
Keeping in mind the tangible and intangible benefits of retrofitting, Di Gregorio believes there is more than enough evidence to drive building owners to invest in such initiatives. “If building owners are not thinking about retrofits, they definitely should!” he says. “Retrofit projects tend to have very favourable returns. We are observing that for comprehensive retrofits of commercial buildings in Ras Al Khaimah, the payback time is 3-5 years. And the contracting standards that are being adopted often provide forms of guarantees for the investor on those returns.”
Jha, agreeing, says that in spite of the change in the occupancy profile of buildings, property owners must continue to retrofit within the built-environment. “Retrofitting of existing buildings offers tremendous opportunities for improving asset performance in terms of utilities,” he says. “Retrofitting also offers a potential upside in the overall performance of the building through improved energy efficiency, increased staff productivity, reduced maintenance costs, and better thermal comfort.” Jha believes that such key drivers should serve as a motivation and incentive for building owners, who are on the fence about investing in retrofit projects.
Retrofitting in Kuwait, Oman and the UAE
COVID-19 has had a significant adverse impact on organisations, people’s health, their livelihoods and the economy at large in the GCC region countries, says Ashok Jha, Head, FM & Retrofit Projects, Universal Voltas LLC. However, Jha is quick to point out that while the duration and severity of COVID-19’s impact on economies and sectors will undoubtedly vary, companies and governments in the GCC region have done well to set in motion a “look ahead, anticipate, innovate and adjust” roadmap, which has led the construction sector to focus on energy optimisation and retrofitting in existing buildings, which is a key to sustainable construction.
Citing figures from Global Data, a leading data and analytics company, Jha says that Oman’s construction industry contracted sharply in 2020, plummeting by nearly around -10.3%. “The industry is struggling with challenges presented by the COVID-19 outbreak, low oil prices, and the impact of sovereign credit rating downgrades,” he says. Further compounding the downside risks to the outlook for the industry, the Omani Government has had to rationalise spending.”
Jha adds that given the limited prospects for the government to boost investment in infrastructure and other investment projects, a recovery in the construction sector is expected to be very slow. “Global Data currently expects the construction industry to fall further in 2021, with output contracting by -5.8%,” he says. “The fiscal plan by the Oman Government is intended to reduce public debt, increase the state’s reserves, and diversify revenue away from the oil sector.”
Owing to these factors, Jha believes that new construction spend will be very minimal, and more impetus will be on the retrofitting, deep retrofitting, fit-outs and energy performance optimisation in the built-environment in Oman.
Kuwait has faced similar challenges, Jha says, adding that the construction market shrunk in the year 2020 at about -9.5% approximately, as per Global Data. “The construction industry is struggling with the challenges presented by the outbreak of COVID-19, low oil prices and the impact of sovereign credit rating downgrades,” he says. “Because of this, focus is more towards existing buildings in Kuwait.”
Jha adds that within the built-environment in Kuwait, residential buildings constitute around 81%, commercial buildings are 11%, whereas government buildings constitute four per cent; the remaining four per cent includes commercial, industrial, agricultural and services. “Also, Kuwait has one of the highest per capita electricity consumption and carbon footprint globally, which further necessitates the retrofitting of the buildings to make them more sustainable,” he says. “All the above factors, along with the economic strain, is forcing Kuwait to focus on energy conservation, deep retrofitting, retrofitting and fit-outs in the built-environment with a very minimal spending on new construction.”
Sharing observations on the UAE market, in particular, Jha says that the COVID-19 outbreak, coupled with low oil prices, has led the construction output in the UAE to contract by nearly 4.8% in 2020, but that a rebound is expected in 2021, as per Global Data. “New project opportunities are expected to be minimal in the coming quarters, as the government is consolidating its widening fiscal debt and COVID-19-related force majeure,” he said. “Over the medium- to longer-term, government investment will remain focused on upgrading physical infrastructure and reforming the financing and regulatory environment.”
Jha adds that the UAE has set high targets for building retrofit, which are reflected in the UAE Energy Strategy 2050 and the Dubai Integrated Energy Strategy. “The latter targets an overall 30% reduction in energy and water use by 2030,” he says. “To support this, Etihad ESCO aims to retrofit 30,000 buildings in the next 10 years and generate 1.68TWh energy savings and around 5.64 BIG of water savings by year 2030.”
How to kill enveloped viruses in just 30 minutes
Poor ventilation in closed indoor environments is associated with increased transmission of respiratory infections. There have been numerous SARS-CoV-2 transmission events associated with closed spaces, including some from pre-symptomatic cases. The role of ventilation in preventing SARS-CoV-2 transmission is not well-defined – that is, by preventing dispersal of infectious particles in small waterdrops to minimise the risk of transmission or preventing transfer of an infectious dose to susceptible individuals.
SARS-CoV-2 is thought to be primarily transmitted through large respiratory droplets; however, an increasing number of outbreak reports implicate the role of aerosols in SARS-CoV-2 outbreaks. Aerosols consist of small droplets and droplet nuclei, which remain in the air for longer than large droplets. Studies indicate that SARS-CoV-2 particles can remain infectious on various materials, such as air conditioning surfaces in air ducts and air handlers, as well as in aerosols in indoor environments, with the duration of infectivity depending on temperature and humidity.
While HVAC coatings are often the most cost-efficient insurance for the longevity of your air-handling system, there’s much more to them than just increasing your building systems’ lifespan. The rising demand for antimicrobial coatings was triggered by the COVID-19 pandemic and tenants worried about their wellbeing from airborne diseases. In the same category, antimicrobial coatings can make a huge difference for indoor air quality and occupant safety. There are a number of HVAC coatings that drive energy savings, primarily desiccant-coatings.
Found on AHU heat exchangers, coils and in duct systems, they enable recovering heat and moisture, which then helps building owners to save on operational cost. Recent studies have uncovered an extreme antimicrobial effect of desiccant coating systems, in high relative humidity, as present in air conditioning systems. It appears the surfactants can break the exterior protein of a virus or bacteria strain. Once the protein is destroyed, the virus cannot attach to cells and transfer or alter human ribonucleic acid (RNA).
In many circumstances, once microbes have begun to proliferate on a painted surface, constant cleaning and disinfecting is required to keep growth under control, which is highly unwanted inside an air conditioning system. Recognising that the ability to clean constantly is unreasonable in most air conditioning systems, the best weapon against corrosion and microbial growth is an antimicrobial paint that prevents growth of, or eliminates, bacteria and viruses. Both the coating and the possible active ingredient should not produce any environmental, safety or health issues during application. Any off-gas from the film is unwanted, because ideally, the coating must be applied to air conditioning systems in operation without any concern of release of poisonous additives.
Antimicrobial efficacy based on silver ions
Generally, an antimicrobial surface contains an additive, like Agion, which inhibits the antimicrobial property that is composed primarily of silver ions, which have been proven in antimicrobial use throughout history. It incorporates silver ions inside a zeolite carrier, providing an area for these ions to exchange with other positively charged ions – often sodium – from the moisture in the environment.
Once exchanged, these now “free” silver ions are attracted to oppositely charged hydrogen ions, commonly found in most bacteria and microbes. The bacteria and microbes’ respiration and growth are now abruptly halted, since the hydrogen ions are no longer available. Silver based antimicrobial coatings contain a pesticide additive that evaporates slowly from the coating surface and raises questions on the durability of discharge. In Europe and North America, these coatings require a registration by the government authorities.
Antimicrobial efficacy based on desiccation
Enveloped viruses, like the H1N1 influenza virus, Corona (COVID-19) and bacteria have membranes of protein and enzymes to protect the infecting contents. The spreading of the viruses and bacteria in closed spaces and air conditioning systems is carried out by smaller aerosols. Alternative antimicrobial functionality is based on desiccation, a physical process to extract the moisture from the virus and bacteria particles. This approach may seem relatively primitive; however, it is extremely effective in slowing down or even preventing microbes from spreading and transmission. This method is similar to other physical treatments, such as UV irradiation, filtering and heating.
Desiccant coatings inactivate a wide variety of microbes that adhere to the surface through their hydrophilic surface properties. The antiviral functionality of the coating has been tested on the Phi6 virus, which is commonly used as surrogate for enveloped Corona viruses.
A recent study shows that a desiccant coating can have an extremely quick kill-rate of enveloped viruses after just 30 minutes.
Further studies have proven that strong antimicrobial working was additionally confirmed. Surface activity results in full kill-rates of > 99,99%, which were confirmed on the following micro-organism strains:
- Klebsiella Pneumoniae
An important note should be added to this paper: No claim or assertion should be made that the antimicrobial properties in the coating will improve air quality or eliminate the threat of disease-causing microbes in the air supply system. A healthy indoor air system is highly dependent on a combination of design, maintenance and cleaning measurements that are incorporated in the air conditioning system and facility management procedures.
- Knibbs LD, Morawska L, Bell SC, Grzybowski P. Room ventilation and the risk of airborne infection transmission in 3 health care settings within a large teaching hospital. Am J Infect Control. 2011 Dec;39(10):866-72.
- Lu J, Gu J, Li K, Xu C, Su W, Lai Z, et al. COVID-19 Outbreak Associated with Air Conditioning in Restaurant, Guangzhou, China, 2020. Emerg Infect Dis. 2020 Apr 2;26(7).
- Rothe C, Schunk M, Sothmann P, Bretzel G, Froeschl G, Wallrauch C, et al. Transmission of 2019-nCoV Infection from an Asymptomatic Contact in Germany. N Engl J Med. 2020 Mar 5;382(10):970-1.
- World Health Organization (WHO). Natural Ventilation for Infection Control in Health-Care Settings. 2009 [updated 4 May 2020].
- Ong SWX, Tan YK, Chia PY, Lee TH, Ng OT, Wong MSY, et al. Air, surface environmental, and personal protective equipment contamination by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from a symptomatic patient. Jama. 2020;323(16):1610-2.
- Bahl P, Doolan C, de Silva C, Chughtai AA, Bourouiba L, MacIntyre CR. Airborne or droplet precautions for health workers treating COVID-19? The Journal of Infectious Diseases. 2020.
- Dietz L, Horve PF, Coil DA, Fretz M, Eisen JA, Van Den Wymelenberg K. 2019 Novel Coronavirus (COVID19) Pandemic: Built Environment Considerations To Reduce Transmission. mSystems. 2020 Apr 7;5(2):e00245-20.
8 Evaluation of Phi6 Persistence and Suitability as an Enveloped Virus Surrogate Aquino de Carvalho, Nathalia; Stachler, Elyse N.; Cimabue, Nicole; Bibby, Kyle Environmental Science & Technology (2017), 51 (15), 8692-8700CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
Recent outbreaks involving enveloped viruses, such as Ebola virus and SARS COVID-2, have raised questions regarding the persistence of enveloped viruses in the water environment. Efforts have been made to find enveloped virus surrogates due to
challenges investigating viruses that require biosafety-level 3 or 4 handling. In this study, the enveloped bacteriophage Phi6 was evaluated as a surrogate for enveloped waterborne viruses. The persistence of Phi6 was tested in aq. conditions chosen based on previously published viral persistence studies. Our results demonstrated that the predicted T90 (time for 90% inactivation) of Phi6 under the 12 evaluated conditions varied from 24 minutes to 117 days depending on temperature, biological activity, and aq. media compn. Phi6 persistence was then compared with persistence values from other enveloped viruses reported in the literature. The apparent suitability of Phi6 as an enveloped virus surrogate was dependent on the temperature and compn. of the media tested. Of evaluated viruses, 33%, including all conditions considered, had T90 values greater than the 95% confidence interval for Phi6. Ultimately, these results highlight the variability of enveloped virus persistence in the environment and the value of working with the virus of interest for environmental persistence studies.
- The use of bacteriophages of the family Cystoviridae as surrogates for H5N1 highly pathogenic avian influenza viruses in persistence and inactivation studies
Adcock, Noreen J.; Rice, Eugene W.; Sivaganesan, Mano; Brown, Justin D.; Stallknecht, David E.; Swayne, David E.
Journal of Environmental Science and Health, Part A: Toxic/Hazardous Substances & Environmental Engineering (2009), 44 (13), 1362-1366CODEN: JATEF9; ISSN:1093-4529. (Taylor & Francis, Inc.)
Two bacteriophages, .vphi.6 and .vphi.8, were investigated as potential surrogates for H5N1 highly pathogenic avian influenza virus in persistence and chlorine inactivation studies in water. In the persistence studies, .vphi.6 and .vphi.8 remained infectious at least as long as the H5N1 viruses at both 17 and 28 degrees C in fresh water, but results varied in salinated water. The bacteriophage .vphi.6 also exhibited a slightly higher chlorine resistance than that of the H5N1 viruses. Based upon these findings, the bacteriophages may have potential for use as surrogates in persistence and inactivation studies in fresh water.
- Systematic Review and Meta-Analysis of the Persistence and Disinfection of Human Coronaviruses and Their Viral Surrogates in Water and Wastewater, Andrea I. Silverman and Alexandria B. Boehm, April 2020
- Determination of the Antiviral Activity of Water-Based Coating for Air Conditioning Applications against phi6 Bacteriophage using a Method Based on ISO 21702:2019, the laboratories of Industrial Microbiological Services Ltd at Pale Lane Hartley Wintney, Hants, RG27 8DH, UK. December 2020
The writer is with Aqua Aero Coatings and may be contacted at firstname.lastname@example.org
Daikin India acquires Citizen Industries
GURGAON, India, 16 December 2020: Daikin Airconditioning India acquired India-based AHU manufacturer, Citizen Industries through a share-purchase agreement, signed on December 15, the former said through a Press release.
According to Daikin, the acquisition will provide prominence to its current infrastructure influence and help increase its penetration across various applications.
Citizen Industries has two manufacturing units, a big base of R&D engineers and service technicians that Daikin said would complement its people strength. The integration of the two companies, Daikin added, would result in joint sales velocity; acquiring of ongoing air-side maintenance contracts; expansion into the applied and VRV solution business, including air side; a horizontal collaboration with American Air Filter (AAF); and catalysing economies of scale at Daikin’s Neemrana factory in the western Indian state of Rajasthan and its R&D centre.
Daikin said its acquisition of Citizen Industries mirrors its assertive philosophy of identifying opportunities ahead of time and building value around its offerings, while keeping customer requirements at the forefront to create a sustainable business, faster than the rest.