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Advocating for change is never easy. We must do better to provide a safe learning environment.
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I. Lobby Congress to ensure OSHA regulations clarify responsibilities of employers and penalties for non-compliance. We must advocate to ensure we work and learn in a safe environment . This must include updated standards for the air we breath.
1. Increase all HVAC to Merv 13 filters
2. Install CO2 monitors in any interior work environment.
3. Air purifiers or Corsi-Rosenthal Boxes
4. Increase ventilation
1. Funds specifically for new or upgarding HVAC systems in all schools.
a. That are capable of filtering out 99% of pathogens.
b. Increase the air exchange rate to maintain CO2 at 600 ppm
"My son took a CO2 monitor to his school, and it measured > 2300 ppm. He asked to open the windows. They did and it went down to between 600-800 ppm!"
The virus particles leave the mouth or nose of a sick person and float through the air like smoke. If you breathe in enough of them, you can get sick. We have to remember that children and young adults can be contagious, without having symptoms or may have very mild symptoms. This does not necessarily mean it is less dangerous or that it won't spread to another person or another child who then infects their parent or grandparent that could suffer much more severe consequences, or worse, die.
Ventilation is when indoor air is replaced with outdoor air. This gets rid of the virus particles and replaces them with virus-free outdoor air when you have good ventilation.
When people exhale, approximately 4-5% is CO2. If we are in a poorly ventilated space that can build up. Measuring CO2 in a room tells us how much air has been breathed in and exhaled.
Before COVID, we already knew that students in schools with better ventilation did better on tests, missed less school, and had less asthma and other breathing problems. Other studies show that for every dollar an employer spends to improve ventilation, they get back more in increased employee productivity and fewer sick days. All of this happened before COVID, but it is even more important now.
Ventilation equipment that we depend on to bring in fresh air often stops working and no one notices. With a CO2 sensor, you can check to see if something needs to be fixed right away.
CO2 levels between 1,000 ppm -2,500 ppm can make you tired, make it hard to concentrate, and make you feel uncomfortable. (4) This line is often crossed in classrooms. Your kids might be tired not because of the subject or the teacher, but because there isn't enough oxygen.
ASHRAE, an organization that has been responsible for setting ventilation rates in buildings, has stated that CO2 levels below 1000 ppm has long been considered an indicator of good air quality but what is meant by good?
" CO2 concentrations in outdoor air typically range from 300 to 500 ppm. Thus indoor CO2 concentrations of 1000 to 1200 ppm in spaces housing sedentary people is an indicator that a substantial majority of visitors entering the space will be satisfied with respect to human bioeffluents (body odor). " (5)
So by good, they mean you won't necessarily notice other peoples body odor. We are on a mission to significantly limit transmission of a highly contagious airborne virus.
The French High Council of Public Health recommends a threshold of 800 ppm in all public buildings due to COVID. Levels above 800 ppm require action improving ventilation or reducing occupancy. "The HCSP indicates that the air change rate can be easily approximated by measuring the carbon dioxide concentration in the air at representative points and periods during occupancy. A CO2 concentration above a threshold of 800 ppm should in all cases lead to the room not being occupied and to action being taken in terms of ventilation/air renewal and/or reducing the number of people admitted to the premises of an ERP." (6)
In France, over 800 ppm requires clearing the room. It should no longer be occupied. The U.K. adopted that standard in 2021, although all records of it have been removed today. 800 ppm is the absolute maximum therefore, the goal should be no more than 600 ppm to ensure enough ventilation.
In the past, 800 ppm to 1,000ppm was relatively safe but in order to significantly reduce transmission of COVID, flu, RSV and other airborne viruses, we have to do better. That means working to set the new standard. Maintain CO2 levels at 600 ppm using automated sensors so this is hands off, but can be monitored via public or at least building occupants or parents in the case of children.
Disease prevention isn't the only reason to keep an eye on CO2 levels in each classroom, but if you want to stop viruses and other diseases from spreading through the air, it can help to understand and keep an eye on CO2 levels.
The simplest way to improve ventilation is to open windows and doors as much as possible. You can place fans in the windows or doors to further increase the airflow.
Most commercial spaces use units that heat and cool the space and also provide ventilation, so make sure the thermostat is set to “on” or “fan” and never leave it in “auto” when there are people there. You can put it in “auto” at night when everyone leaves.
The furnace in your home isn't usually connected to outdoor air unless you have a heat recovery ventilator (HRV) or energy recovery ventilator (ERV) connected to it, so running your furnace all the time might not help reduce the CO2 levels in your home.
If you have a MERV-13 filter in your furnace and run it all the time, it can aid in filtering virus particles out of the air.
"Although CO2 is denser than air, CO2 stratification occurs because exhaled breath is warm, and is either immediately entrained into the main body plume or rises as a secondary plume where it typically settles at an intermediate height before being entrained and carried into the upper layer. (Bhagat et al., 2020). Pei et al. (2019) showed that temperature and CO2 stratification is particularly pronounced in mechanically ventilated buildings using displacement ventilation." (2)
"This study highlights the importance of appropriate HVAC systems in public buildings, as these play a key role in preventing the spread of airborne diseases, as well as other particulate matter. We suggest that there should be information about the HVAC system at the entrance to every building to increase awareness among visitors. The current focus on ventilation due to COVID-19 could benefit the global fight against TB, as the mode of transmission is similar for both and adoption of HVAC systems is a priority in many settings. Our observations in India may also be true for urban buildings in other countries, which are dealing with a similar air pollution crisis and require dilution ventilation. (3)
CDC and EPA Recommendations
Strategies for Improving Ventilation
The below resources are based on current recommendations by the Center for Disease Control and Prevention (CDC) and the Environmental Protection Agency (EPA).
The Centers for Disease Control and Prevention (CDC) and the Environmental Protection Agency (EPA) outline ways that schools and IHEs can improve ventilation, including:
Bringing in as much outdoor air as possible.
Open windows wherever it is safe to do so, including in classrooms and on school buses and other transportation. Where safe, opening doors can also improve airflow. Using child-safe fans in accordance with CDC guidance increases the impact of open windows and doors.
Hold classes, activities, and meals outdoors when safe and feasible.
Using heating, ventilation, and air conditioning (HVAC) settings to maximize ventilation.
Service or upgrade HVAC systems consistent with current industry standards.
Set systems to bring in as much outdoor air as the system can safely support, including for 2 hours before and after occupancy.
Reduce or eliminate air recirculation in consultation with an HVAC expert.
Disable demand-controlled ventilation controls. In classrooms or buildings controlled at the thermostat, set the fan to the “on” position instead of “auto,” which will operate the fan continuously, even when heating or air conditioning is not required.
Use a scheduled inspection and maintenance program for HVAC systems to allow repair, modification, or replacement of equipment.
In consultation with HVAC experts and health officials, consider changing HVAC system filters more often than recommended by normal maintenance requirements.
Ensuring exhaust fans in restrooms and kitchens are working properly and use them during occupancy and for 2 hours afterward to remove particles from the air. Keep all fans and filters clean to maximize airflow.
Filtering and/or cleaning the air.
Upgrade HVAC filters to minimum efficiency reporting value (MERV)-13, or the highest MERV rating a building’s ventilation system can accommodate to improve air filtration as much as possible without significantly reducing airflow.
Ensure HVAC filters are sized, installed, and replaced at least as frequently as according to the manufacturer’s instructions.
Consider using portable air cleaners that use filtration technology, such as high-efficiency particulate air (HEPA) filters. A July 2021 CDC report shows that HEPA filters can reduce exposure to the virus that causes COVID-19, particularly in combination with universal and correct mask wearing. Select air cleaners of appropriate capacity for the space in which they will operate. Portable air cleaners can go in any room of a school building to serve as an additional safety and mitigation layer, including in areas where airflow may be limited, and/or in areas where sick individuals may be present such as a nurse’s office or sick/isolation room.
The CDC and EPA references listed under “Additional Resources” include valuable guidance on the selection of portable air cleaners. CDC guidance on ventilation in the home may be relevant for residential dormitories. Caution: Some products sold as air cleaners intentionally generate ozone and are not safe to use when people are present. Consumers should assess any claims about air disinfection devices to determine whether they have been tested in similar conditions to those where they would be used, including in schools, colleges, and universities.1
Considering the use of portable carbon dioxide (CO2) monitors to verify how well air is circulating in classrooms and other spaces. School maintenance professionals may also use air flow capture hoods, anemometers, and qualitative tracer techniques to assess airflow. Additional information on using portable CO2 monitors is available in the CDC Ventilation FAQ related to CO2 monitors.
Communicating clearly to school communities, parents, students, faculty, and staff, in a language they can understand and in accessible formats, including on district, school, college, or university webpages, how you are assessing and improving ventilation. For example, some districts have performed school building ventilation walk-throughs with community leaders to assess needs and share results and plans for how to improve ventilation. Walking through school or IHE buildings with custodial engineers, parent leaders, teacher or faculty leaders, students, and others is one way to educate your community on how ventilation works within your educational spaces and assess ways that you can target upgrades and updates. Some districts and school leaders have created videos touring the ventilation systems of school buildings and explaining the strategies deployed for effective ventilation in plain language to parents so they understand the school’s approach. In all cases, school leaders can share the ways rooms have been prepared to maximize air flow for in-person learning.
For more information on how ESSER and GEER funds can be used to support these efforts, please see questions B-6 and B-7 of Frequently Asked Questions related to the program. For more information on using HEER funds, see question 24 of the ARP HEERF III FAQs. In addition, for ESSER and GEER, the U.S. Department of Education (Department) has provided supplementary information to States and districts to help them efficiently implement ventilation projects while following applicable requirements. If a district or IHE uses funds for HVAC systems, the Department’s applicable regulations require the use of current American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) standards.
Other than statutory and regulatory requirements included in the document, the contents of this guidance do not have the force and effect of law and are not meant to bind the public. This document is intended only to provide clarity to the public regarding existing requirements under the law or agency policies. This document contains resources (including links to those resources) that are provided for the user’s convenience. Inclusion of these materials is not intended to reflect their importance, nor is it intended to endorse any views expressed or products or services offered. These materials might contain the views and recommendations of various subject-matter experts, as well as hyperlinked text, contact addresses, and websites to information that other public and private organizations created and maintain. The opinions expressed in any of these materials do not necessarily reflect the positions or policies of the Department. The Department does not control or guarantee the accuracy, relevance, timeliness, or completeness of any outside information included in these materials.
CDC information on improving ventilation in schools at https://www.cdc.gov/coronavirus/2019-ncov/community/schools-childcare/ventilation.html, in buildings at https://www.cdc.gov/coronavirus/2019-ncov/community/ventilation.html, and in homes at https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/Improving-Ventilation-Home.html.
EPA resources on indoor air quality tools for schools at https://www.epa.gov/iaq-schools.
Resources related to Lessons from the Field webinar featuring CDC, EPA, and U.S. Department of Education, along with district leaders at https://safesupportivelearning.ed.gov/events/webinar/lessons-field-indoor-air-quality-and-ventilation-america%E2%80%99s-k-12-schools-guidance-and.
CDC Morbidity and Mortality Weekly report on the efficacy of HEPA filters and masking to reduce exposure to the virus that causes COVID-19 at https://www.cdc.gov/mmwr/volumes/70/wr/mm7027e1.htm?s_cid=mm7027e1_w.
ASHRAE guidance for reopening schools at https://www.ashrae.org/technical-resources/reopening-of-schools-and-universities.
National Energy Management Institute and U.C. Davis Energy and Efficiency Institute White Paper on Proposed Ventilation and Energy Efficiency Verification/Repair Program for School Reopening at https://ucdavis.app.box.com/v/ProposedVentilationProgram.
1 Testing should validate both efficacy under as-used conditions and safety for all potential occupants, including those with compromising health conditions. (See the CDC FAQ related to air disinfection devices at https://www.cdc.gov/coronavirus/2019-ncov/community/ventilation.html.) Some indoor air filtration devices use ionization technology, including bipolar ionization technology, which has the potential to create ozone that can irritate the airways, unless specific precautions are taken in the product design and maintenance. (See https://www.epa.gov/coronavirus/air-cleaners-hvac-filters-and-coronavirus-covid-19.)