AHRI MENA, ASHRAE RAL Energy Efficiency Webinar recording now available
DUBAI, UAE, 3 June 2022: AHRI MENA said a recording of the May 18 AHRI MENA, ASHRAE RAL Energy Efficiency Webinar is available for public viewing. AHRI (The Air-conditioning, Heating, and Refrigeration Institute) and the ASHRAE Region-At-Large (RAL) Chapter conducted the webinar, titled Raising the Bar of Energy Efficiency in High Ambient Temperature Regions.
With more countries in the Middle East and North Africa (MENA) region facing mounting environmental challenges, the webinar provided attendees with insight into regulations, energy performance standards, and building codes aimed at improving energy efficiency and supporting ambitious green targets, AHRI MENA said.
Khalil Issa, AHRI MENA Executive Director and Nabil Shahin, Technical Director, discussed key drivers for facilitating compliance with minimum energy performance standards (MEPS) and green building codes, principally the AHRI Performance Certification Program, which uses independent, third-party testing to accomplish that goal.
ASHRAE representatives, Richie Mittal and Dr Samir Traboulsi discussed global and regional regulatory and energy efficiency issues and introduced ANSI/ASHRAE/IES Standard 90.1. Considered the gold standard for energy efficiency, Standard 90.1 was examined in terms of its structure and compliance mechanisms in the context of ASHRAE 189.1 and the International Green Construction Code standards.
“With AHRI’s product performance and rating standards being intrinsically referenced in green building codes and ASHRAE 90.1, only AHRI certification allows the proper verification of equipment efficiency and serves as the best path for regulatory code and MEPS compliance,” Issa said.
AHRI MENA said a recording of the webinar is available here. It suggested to visit the website to learn more about AHRI MENA.
JCI: Investments in sustainability have rebounded to pre-pandemic levels
CORK, Ireland, 12 April 2022: Johnson Controls (JCI) announced findings from its 15th annual Energy Efficiency Indicator Survey, which revealed that 62% of organizations surveyed expect to increase investments in energy efficiency, renewable energy or smart building technology in 2022, indicating a return to pre-pandemic levels.
JCI said the latest report by the United Nations Intergovernmental Panel on Climate Change advised that global scale transformation is urgently needed to combat climate change; however, its Energy Efficiency Indicator Survey found that organizations are still facing challenges to accelerate their sustainability efforts in key areas. Almost two-thirds of survey respondents say they struggle to scale sustainability initiatives across buildings, geographies or business units.
“In the face of the multiple and continuous shock waves of the last two years, it is very encouraging to see that building owners and operators are driving forward the kinds of investments that deliver the resilience needed to grow their business and attract and retain the best talent,” said Katie McGinty, Vice President & Chief Sustainability and External Relations Officer, JCI.
“Whether it is the damage delivered by climate-charged destructive natural events, or the health threat of the pandemic, or now, the stark demonstration of the insecurity of world energy supplies, it is clear that taking action to cut energy demand while decarbonizing and cleaning the air are core strategies for companies, governments and institutions to not only survive but to thrive.
Our innovative technologies in heat pumps and our OpenBlue digital platform, plus our Net Zero as a Service partnership offering, are exactly the right tools at the right time for leaders determined to stay well ahead of challenges and deliver new opportunities for their business or organization.”
JCI said the survey revealed that planned investment in energy generation or storage has grown significantly over five years, likely in response to the global focus on decarbonization, and as part of that effort, electrification.
More than a third of respondents plan to replace fossil fuel heating equipment with heat pump technology in the next year, which is seven per cent more than what was implemented in the year prior, the company said. Notably, thermal energy storage jumped from 27% to 42% in the last five years, the company said. More than half of respondents implemented electric energy storage in the past year, the company added.
JCI said the survey also found that the United States and Europe still lead the way in every metric of green building planning. The United States had the most respondents who had already achieved green building certification and expect to have a net-zero-energy or carbon building in the next 10 years, JCI said.
Europe had the most respondents planning to attain green building certifications and the most respondents who have established public energy or carbon-reduction goals, with United Kingdom leading with 46% established goals, JCI added.
Compared to its global counterparts, significantly more respondents in the United States plan to implement measures, such as building controls improvements, onsite renewable energy and energy management process, such as ISO 50001, JCI said. Of the countries surveyed, the United Kingdom, France and Japan have the most respondents who expect to increase investment in energy efficiency, renewable energy or smart building technology over the next year, the company said. Still, to reach global sustainability and environmental goals, the world must work collectively to plan for a more energy efficient future and make investments today for the generations to come, it added.
Although global-scale transformation is necessary to course-correct on climate change, organisations are facing barriers to pursuing sustainability initiatives, JCI said. Almost half of the respondents surveyed say their top barrier to pursue energy and building technology improvements is either a lack of funding to pay for improvements (25%) or uncertainty in their return-on-investment (23%), the company said.
Additionally, more than half of respondents pointed to a lack of technology as one of the hindrances to scaling sustainability efforts, JCI said.
The pandemic has also prompted organizations to rethink their technology investment decision-making, JCI said. Protecting the health and safety of building occupants during the coronavirus pandemic was the second most significant driver of investments globally, it said. Additionally, 65% of respondents performed an indoor air quality assessment last year, it added.
Respondents to the survey also said improving occupant health and wellness overall and improving life safety and security were important decision-making factors, JCI pointed out. Over the next 12 months, almost 60% of organizations plan to invest in fire and life safety system and security system improvements to their buildings, it said. Long term, more than two-thirds of organizations believe data analytics and cybersecurity will have an extremely or very significant impact on the implementation of smart buildings over the next five years, it added.
The survey revealed that actionable policies are also important for progressing energy efficiency goals, JCI said, adding that 85% and 72% of respondents, respectively, reported that performance benchmarking, certifications and performance standards for energy codes are critical to improving energy efficiency efforts.
JCI said its Energy Efficiency Indicator Survey collected responses from 1,000 participants globally between November and December 2021.
New global study supports healthy buildings as a critical public health strategy
PALM BEACH GARDENS, Florida, 9 September 2021: For the first time on a global scale, new research has found that healthy buildings with enhanced ventilation can improve the cognitive function and health of occupants, suggesting that ventilation and filtration are pre-eminent healthy building strategies, Carrier Global Corporation said through a Press release. Primary support for the study came from Carrier.
The study, COGfx Study 3: Global Buildings, was led by researchers from the Harvard T.H. Chan School of Public Health as part of the renowned COGfx Study series, which examines the impact of indoor air quality on how people think and feel, Carrier said.
The latest study supports the prior studies’ lab and US findings and further supports that indoor air quality is not only good for people’s health and safety, it’s good for the bottom line, as well – through increased productivity, fewer sick days and better cognitive function, Carrier said.
“As more people move toward returning to offices, schools and recreational activities, the health, safety and intelligence of indoor environments have come into greater focus,” said Dave Gitlin, Chairman & CEO, Carrier. “The COGfx Study continues to demonstrate that proper ventilation and filtration of indoor environments plays an important role across the globe in fostering a proactive health strategy. At Carrier, we are focused on delivering innovative solutions and services that positively impact the health, productivity and cognitive performance of occupants of all buildings.”
The COGfx Study 3: Global Buildings examined the impact of indoor air quality on the cognitive function of office workers across six countries – China, India, Mexico, Thailand, the United Kingdom and the United States. The research found that cognitive function declines as the levels of fine particulate matter (PM2.5) and carbon dioxide (CO2) increase, Carrier said, referencing the study. Higher CO2 can be an indicator of poor ventilation in buildings, the company added.
Importantly, mechanical ventilation, such as an HVAC system with efficient filtration, can help to protect building occupants from the negative cognitive effects of PM2.5 and CO2, Carrier said. In addition to acute impacts on cognitive function, reducing exposure to PM2.5 is associated with many other health benefits, including reductions in cardiovascular disease, asthma attacks and premature death.
While the research focused on office employees in commercial buildings, the takeaways are applicable for all indoor environments, Carrier said, adding that as a company it offers numerous products and services that optimize indoor air quality, including a suite of advanced solutions through Carrier’s Healthy Buildings Program that serves key verticals including, healthcare, hospitality, education, retail and marine.
This latest research builds on previous COGfx studies that demonstrated better thinking and better health can be found inside healthier buildings. The first study found cognitive function test scores doubled when study participants were in simulated green building environments with enhanced ventilation as opposed to conventional building environments. The COGfx Study 2 examined real-world building environments in the United Stayes and showed that employees in green-certified buildings showed 26% higher cognitive function test scores and 30% fewer sick building symptoms versus buildings that were not green-certified.
According to Carrier, the COGfx Study 3 can be found at www.theCOGfxStudy.com.
Green Building Alliance, UN’s partners receive International Climate Initiative Award
PITTSBURGH, Pennsylvania, 21 April 2021: Green Building Alliance (GBA) announced an international collaboration led by the United Nations Economic Commission for Europe (UNECE) to develop a USD 24 million project to improve the energy efficiency of the global building supply chain and its products to deliver high performance buildings. The International Climate Initiative (IKI) of the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety awarded this project, signaling the advancement of a planning phase and full proposal. The launch of the project was announced on April 21 by Elisabeth Winkelmeier-Becker at the UNECE’s 69th Commission meeting.
According to GBS, the award solidifies the Greater Pittsburgh region as a global leader in the expeditious innovation of technologies, products and training aimed at curbing carbon emissions and creating healthy, sustainable buildings. The project presents an opportunity to work with international leaders in the field to identify solutions and strategies, and then implement best practices for the Pittsburgh region. GBA said the IKI award, in conjunction with Pittsburgh’s designation as a UN International Center of Excellence on High Performance Building, confirms GBA as a leader in providing solutions to improve the built environment thereby positively impacting climate change, human health, social equity, and a thriving economy.
“Funding high-performance buildings and retrofitting existing buildings can rapidly reinvigorate local economies, supporting or creating quality jobs through the entire building supply chain while delivering on long-term quality of life for everyone,” said Scott Foster, Director of Sustainable Energy, UNECE, about this innovative work. “Given its size and its history both as a coal-mining and steel-making center and as an example of urban rebirth, Pittsburgh has a lot to offer the cities of the world in terms of its experience and know-how.”
GBA said it is eager to begin the important work. “It is an honor to play such an important role in the US commitment to climate and infrastructure and the need to rapidly transform the building industry,” said Jenna Cramer, Executive Director, GBA. “We have an opportunity to build upon our 28-year history of making Pittsburgh and the Western Pennsylvania region a leadership hub for green buildings and sustainable products. This project is part of our efforts with the Greater Pittsburgh International Center of Excellence, a public private partnership that uniquely positions organizations, researchers, companies, and governments to collectively problem-solve for our region’s future while also connecting on a global platform to share best practices and advance solutions.”
According to GBA, the building and construction sector plays a key role in addressing global issues, including significant emissions reductions, improved energy security and increased circular economy. The sector is integral to achieving the Paris Agreement goals, as it is responsible for approximately 40% of energy- and process-related emissions. The project kick-off will take place in May 2021. Led by UNECE, other partners include UN Environment, UN Development Programme (UNDP) offices in select countries, UN Economic and Social Commission for Asia and the Pacific (UN ESCAP), Passivhaus Institute (Germany), and the Technical University of Denmark. GBA is the only partner in the United States.
The Greater Pittsburgh Center of Excellence current partners include Allegheny County, City of Pittsburgh, Allegheny Conference on Community Development, PA Department of Conservation and Natural Resources, PJ Dick, Fourth Economy, Duquesne Light, Carnegie Mellon University, University of Pittsburgh, Duquesne University, Covestro, Partner4Work, Innovation Works, Phipps Conservatory and Botanical Gardens, other nonprofits, and professionals.
The Crux of building performance
Buildings often do not perform in an optimal and efficient way despite significant investment during design and construction. The reasons can be wide and varied, and there is a certain inevitability that issues during construction will arise, and decisions will be made that could ultimately affect the long-term performance of the building. Building Commissioning, when utilised correctly, is a systematic quality assurance process. It increases the likelihood of buildings operating in line with their design intent, by verifying and documenting the fact that building services are designed, installed, tested and are operating in line with the Owners Project Requirements (OPR). This is primarily done with detailed planning, organisation, coordination and control of all commissioning activities.
Conversely, a building that is not operating in line with project requirements can be inefficient from an energy standpoint, financially uneconomical or suffering from poor indoor environmental quality (IEQ), of which indoor air quality (IAQ) is a significant part. This scenario is particularly prominent across the GCC region, where commissioning is largely misunderstood, under-utilised or is carried out to a low standard. A study by Lawrence Berkeley National Laboratory (LBNL), based on a database of 643 buildings across approximately 100 million square feet of floor space, found the main causes of energy inefficiency in commercial buildings to be ductwork leakage, HVAC systems running and lights left on when spaces are unoccupied, ventilation systems incorrectly balanced, dampers not working and incorrect controls set-up, with an estimated 94.6 billion kilowatt hours annually (BkWh/year) wasted across the top 13 of 100 issues identified. Ductwork leakage was responsible for the greatest energy inefficiency, accounting for 28.6 BkWh/year alone, which has been seen to be a common issue across construction projects in the GCC region.
In addition to energy savings, correcting these issues would likely improve the indoor environment, as the identified issues would have an expected impact on heating and cooling, ventilation of spaces, and potential for drafts and noise. Identifying and correcting these commonly found issues should lead to an overall increase in occupant satisfaction. Commissioning is arguably the most cost-effective process for short-term and long-term advantages to building owners, facility managers and building occupants. However, there are many projects in the GCC region, where commissioning is not utilised or is carried out to a low standard. To put this in perspective, the LBNL study found the median cost for commissioning a new building accounted for 0.4% of the total construction cost. The data received demonstrates a significant 13% energy saving in new buildings, should commissioning and management be implemented effectively. On this basis, the client’s ROI would be 4.2 years.
The purpose of commissioning in new buildings is to ensure the performance requirements of the building owners’ objectives are achieved, making sure the building is operating as efficiently as it can at the time of handover. Commissioning in existing buildings is to validate whether the building is operating efficiently and to identify performance gaps, inefficiencies and improvements needed to return it to an efficient operational condition.
There are several names for commissioning in existing buildings, namely Re-Commissioning, Retro Commissioning and Continuous Commissioning. Retro Commissioning is utilised in buildings where no commissioning was previously performed. Re-Commissioning is typically carried out every 5-10 years and completed when the building use has changed, internal fit-outs completed or equipment and components in the systems are upgraded. Continuous Commissioning is based on frequently monitoring the building use, diagnosing improvements and fine-tuning the building performance.
Re-Commissioning and Continuous Commissioning are beneficial, as they allow flexibility for changing the use of internal spaces without affecting the building’s performance. The way a building is used and operated is often different from the condition predicted during design stage, where assumptions are made for occupant density, temperature set-points, control schedules and operation of HVAC systems. A major factor is occupant behaviour, which is difficult to predict and cannot be known at the time of design. The use of the building compared to the predicted design is monitored and changes made to fine-tune the system performance. A study by Wang L, et al (Uncertainties in energy consumption introduced by building operations and weather for a medium-size office building) showed poor practice in building operation can result in an increase in energy use of 49-79%, and good practice can reduce energy consumption by 15-29%.
Commissioning as a process has become more prevalent in the GCC region in recent years, with several high-profile developers, project management companies and consultants specifying this as a requirement. As an example of implementing commissioning in the GCC region, the Dubai Green Building Regulations and Specifications (DGBR) outlines requirements for commissioning in new as well as existing buildings, highlighting the value of commissioning in securing a green future for Dubai.
To take this a step further, the regulations in the GCC region could outline the requirement of commissioning as a process by referencing publications such as CIBSE Commissioning Code M – Commissioning Management, BSRIA Model Commissioning Plan or ASHRAE Standard 202 – Commissioning Process for Buildings and Systems, which are useful publications for capturing the commissioning process throughout the lifecycle of a building.
To enhance this, it would be beneficial to specify requirements of who can complete the commissioning and management, and the level of training and experience needed. Commissioning is often completed by an independent company, whose role is to ensure compliance with the OPR; the impartial nature is part of the value of commissioning. Unless regulations specify commissioning must be independent, this allows ‘in-house’ commissioning to be completed, which is not unbiased and, citing from experience, often results in ‘covering up’ issues identified instead of resolving them.
In comparison to the UK Building Regulations, commissioning of building services is a key requirement identified, and for buildings to conform to the energy efficiency requirements, CIBSE and BSRIA methodology are to be followed, and the process should be overseen by someone suitably qualified by relevant training or experience. The regulations cite membership of the Commissioning Specialists Association (CSA), the Commissioning Group of the Building and Engineering Services Association (B&ES) and Lighting Industry Commissioning Scheme as a way of demonstrating this.
The writer is Senior Commissioning Manager, AESG, and Committee Member, Commissioning Specialists Association (GCC). He may be reached at firstname.lastname@example.org
‘The cost of ignoring much-needed IAQ upgrades is far greater’
Amid the celebratory news of the roll-out of vaccination programs around the globe, we must all remember one of the biggest lessons that COVID-19 taught the world: Buildings – as they are designed, constructed, and operated and maintained – play a significant role in the health and wellbeing of not only their occupants but also the people and communities around them. These include our private commercial office buildings, residential buildings of all sizes, hospitals, entertainment venues, schools, public buildings and more.
We have also learned that infrastructure inequities in cities, states and countries across the globe – including those in transportation, healthcare, agriculture and housing – matter and have a big role to play when it comes to effectively managing a health crisis. And sadly, we learned that much like climate change, a pandemic will also disproportionately affect those with the least amount of resources.
The successful development of a vaccine for COVID-19 does not mean that we do not need to develop new practices when designing the places, spaces and communities around us. Why? Because vaccines are only one component of how we will recover and move forward. This is not a once-in-a-generation crisis. As a global community of sustainability and health professionals, we must embrace the lessons learned about virus transmission and apply them to ensure a permanent recovery and resiliency plan. History cannot repeat itself; the cost to humanity is too great.
This is a point in time when leadership matters. This is a point in time for deep inflection. And this is a point in time for purposeful and forward-looking action. We now have the opportunity – and a moral obligation – to completely re-think how our buildings and spaces should be designed, constructed, operated and maintained. We must turn our buildings and spaces into places that positively contribute to our health and wellbeing. That means that we have to take a fresh and honest look at the inequities in the communities around us and build back better with an eye toward achieving resiliency and equity. Multiple studies, including one just released by Oxfam, have found that the world’s richest people have made significant financial gains during COVID-19, while the world’s poor have fallen even further behind.
At USGBC and GBCI, we believe that better buildings and communities equal better lives. That’s why we are dedicated to continuing to invest in LEED, the world’s most widely used and trusted green building certification program. The success of LEED around the world is a testament to its effectiveness. As of this writing, we have more than 100,600 registered and certified LEED commercial projects, nearly two million registered and certified LEED residential units, projects in 181 countries and territories and nearly 205,000 LEED APs implementing the rating system around the world. Much like LEED’s commitment to environmental sustainability, human health and wellness strategies have been a foundation of the LEED program since its beginning, with over 70% of the rating system’s credits tying back both directly and indirectly to human health and wellness.
We know that addressing the systemic challenges revealed by COVID-19 won’t happen overnight and without significant planning. And while we know that addressing these systemic needs will not come without significant investment, we also know that healthy people, in healthy places and spaces, equal a healthy and robust global economy – and that the price we will pay for not addressing these needs will be far greater than addressing them now.
We can start by focusing our efforts on one of the primary targets of preventing virus spread: Indoor air quality (IAQ). Public health data has shown that buildings are safer to occupy when their mechanical systems, especially HVAC systems, promote good ventilation, air scrubbing and purification and enhanced outside air exchange. While these enhancements alone cannot eliminate the risk of virus transmission, they are a critical component of a larger mitigation strategy. Upgrades to outdated and inefficient HVAC systems in existing buildings across the world have been delayed for decades owing to cost concerns. However, the cost of ignoring these needed upgrades is far greater, as the pandemic has demonstrated in human lives lost, shuttered economies and schools and overburdened healthcare delivery platforms. Now is the time to invest in a resilient future and build back the trust between people and the buildings around them.
One way that USGBC and GBCI have strived to build back trust between people and the buildings around them is through our LEED Safety First Pilot Credit, related to managing IAQ as a component of our LEED green building rating system. The pilot credit builds on existing IAQ credits in LEED and helps building owners and managers ensure that IAQ systems are operating as designed. It also helps determine temporary adjustments to ventilation that may minimize the spread of COVID-19.
The pandemic has also called attention to the condition of schools. For well over a decade, USGBC has been advocating for a major and long overdue global investment in school buildings. We have already seen some of the adverse effects of schools being shut down and students being forced to learn from home for nearly a year, and the value placed on schools and in-person education is as high as ever. Now is the time to leverage that goodwill and invest in these facilities on a global scale, so that such disruptions never happen again. We need to ensure that every school across the globe has proper ventilation, air purification equipment, carbon dioxide monitors and proper outdoor air exchange in order to reduce the risk of spreading airborne pathogens as a key component in their back-to-school engagement strategy. Every student needs to have a chance to thrive, and a key component of that is a healthy school building.
These investments alone will not create a strong, healthy and resilient planet. We also need to look at cities and their infrastructures. Despite predictions of an exodus of people leaving dense urban population centers for the suburbs, we did not see the global abandonment of cities during the pandemic. Not everyone has the resources to simply pack up and leave, and many rely on the resources that cities provide. And many of those that did leave their cities simply relocated to other cities.
Cities that set themselves apart through substantial investments in sustainability, health and wellness, resiliency and equity will be the leaders of tomorrow. People by their very nature need to feel confident, comfortable and safe with the community around them. That’s why it is critical to provide a framework that communicates the importance of investing in urban infrastructure.
I am proud of the 114 cities and communities across the globe who have certified through the LEED for Cities and Communities rating systems, including the City of Dubai and the King Salman Energy Park (SPARK) project. These rating systems revolutionize the way cities and communities are planned, developed and operated, in order to improve their overall sustainability and quality of life. LEED for Cities and Communities is aligned with the United Nations Sustainable Development Goals and encompasses social, economic and environmental performance indicators and strategies with a clear, data-driven means of benchmarking and communicating progress. The rating system also addresses pandemic-specific challenges with two LEED Safety First Pilot Credits, one addressing the preparedness for pandemic planning and the other ensuring social equity in pandemic planning.
At some point, we will enter a post-pandemic world. However, leaders must not then forget the lessons learned from COVID-19. We must remain focused on letting science, data and the health and wellness of future generations drive each and every decision that we make. Better buildings and communities do lead to better and healthier lives. Let’s make that our collective legacy.
Mahesh Ramanujam is President and CEO of the U.S. Green Building Council (USGBC) and Green Business Certification Inc. (GBCI). He may be contacted at email@example.com.
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.