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CNG Air Quality Management Policy and Protocols : AQI Home


We are committed at CNG to educating the whole child, providing facilities that meet the needs of our learning program, and ensuring the well-being of all community members. As a result, we work diligently and proactively to make certain that all students and staff enjoy a safe and healthy campus, including monitoring air quality and taking appropriate measures in accordance with research and best practices in Colombia, the U.S., and internationally. This policy also reflects the school’s full alignment with the Ministerio del Medio Ambiente's AQI protocol published in its 2017 resolution. CNG will always carefully consider official Colombian government agency recommendations and mandates, if those supersede U.S. or international guidance or standards.


CNG developed this policy and set of protocols to help guide the school’s planning and decision-making efforts with respect to air quality on our campus in order to promote a healthy and safe environment for our community members.


With the growing concern of air quality taking place worldwide, current research indicates that exposure to air pollution causes negative health impacts. Studies on long-term health effects typically focus on individuals who are exposed to unhealthy air for an extended period of time, often over many years. However, evidence also indicates that short-term exposure to unhealthy air can also create health problems. Children are at an increased risk because their lungs are still growing, and they tend to be more physically active. Additionally, they are more likely to have respiratory illnesses that can be aggravated with elevated levels of air pollution. Therefore, monitoring air quality and responding appropriately based on scientific data will remain an important component in our commitment to protecting the health and safety of our students and staff.  






0 - 50

Good Air quality is considered satisfactory, and air pollution poses little or no risk. Level 1
0 - 150

Periodic Monitoring 

51-100 Moderate

Air quality is acceptable; however, for some pollutants, a moderate health concern may occur for a very small number of people. For example, people who are unusually sensitive to ozone may experience respiratory symptoms.

101 - 150 Unhealthy for Sensitive Groups

Although this AQI range might not affect the majority of the general public, people with lung disease, older adults, and smaller children are at a greater risk from exposure to ozone, whereas persons with heart and lung disease, older adults, and children would be at greater risk from the presence of particle pollution in the air.

151 - 200 Unhealthy

Most people may begin to experience some adverse health effects at this AQI level, and members of the most sensitive groups may start to experience more serious side effects.

Level 2
151 - 200

PS/ES/MS/HS Moved Indoors

 Mask Use Advised

201 - 300

Very Unhealthy

This high level would require notification of a schoolwide health alert signifying that everyone may experience more serious health effects.

Level 3A
201 - 250

PS/ES/MS/HS Outdoor Activities Postponed, Canceled, or Moved Indoors with Non-vigorous Physical Movement

Masks Recommended

Level 3B
251 - 300

Possible Early Dismissal or School Closure with Shift to Virtual Learning

Masks Strongly Recommended

301 - 500 Hazardous

The highest AQI level would trigger a health alert to warn of emergency conditions. Hazardous air quality would affect the entire population regardless of prior personal risk factors.

Level 4

School Closed with Shift to Virtual Learning


CNG monitors air quality by taking multiple measurements on campus using the school’s own AQI monitoring system and a real-time AQI feed from the following website: In order to ensure that determinations about air quality levels err on the side of caution, CNG averages the AQI measurements taken on site along with the data points reported for Bogota. 

Although many international schools currently use an AQI of 250 as the threshold for acceptable conditions for outdoor learning, play, and sports, the CNG Administration and Board of Directors decided to establish an AQI range of 151-200 for all students and staff. 

CNG conducts ongoing AQI measurements throughout the school day at approximately 30 different testing locations across the entire school campus. AQI quality levels are checked each day by 6:30 a.m., 10:00 a.m., and 1:30 p.m.

If the AQI falls between 151 and 200, staff and students will remain indoors for all learning programs, including physical education, recess, extracurriculars, and sports. Face mask use is advised when air quality is measured at this level. If the AQI moves above 200, all student and staff outdoor activities will be postponed, canceled, or moved indoors with non-vigorous physical movement, and face masks are highly recommended. The CNG Administration, working in conjunction with the Board of Directors, reserves the right to schedule an early release or cancel on-campus classes and switch to a virtual learning modality if the air quality places the health and well-being of students and staff at high risk.

Fieldtrips or other outdoor events, such as sports competitions, might be allowed to proceed when AQI levels on campus exceed the established protocol limits, but only when taking place in indoor environments or at locations where AQI measurements remain below our school’s established thresholds. 

For those with medical conditions that cause risk factors, AQI guidelines suggest that those with respiratory problems should limit the intensity of outdoor activity when AQI readings indicate moderately polluted conditions (AQI 101-150), and they should remain inside when AQI readings indicate unhealthy air quality (AQI 151-200+). CNG recommends that families inform the school nurses and homeroom/advisory teachers if their children have respiratory problems, and parents should advise their children about these activity restrictions.


Air Quality Index: The Air Quality Index (AQI) signifies the system used to warn the public when air pollution reaches unhealthy levels. The AQI tracks ozone (smog) and particle pollution (tiny particulates from smoke, power plants and factories, vehicle exhaust, and other sources), as well as other widespread air pollutants. 

Environmental Protection Agency: The Environmental Protection Agency, or EPA, functions as an independent agency of the United States government tasked with protecting human health and the environment. The EPA established an AQI for major air pollutants regulated by the U.S. Clean Air Act. Each of these pollutants, including particle pollution, has a national air quality standard set by the EPA to protect public health.

Particle Pollution: Particle pollution, also known as particulate matter or PM, reflects a general term used for a mixture of solid and liquid droplets suspended in the air. Particle pollution comes in many sizes and shapes and can be made up of a number of different components, including acids, inorganic compounds, organic chemicals, soot, metals, soil or dust particles, and biological materials.

Particulate Matter 2.5 (PM2.5): Particulate Matter 2.5 represents fine particles generally 2.5 µm in diameter or smaller. This group of particles also encompasses ultrafine and nanoparticles, which are generally classified as having diameters less than 0.1 µm. CNG routinely monitors PM2.5 because it can enter the lungs and the bloodstream.

When the AQI reaches the threshold levels described above, the following notifications will be sent to parents and staff:

If the AQI reaches a level between 151 and 200, staff will be notified that all learning programs and activities must take place indoors. Parents will also be notified about these protective measures. 

If the AQI exceeds 200, all student and staff outdoor activities will be postponed, canceled, or moved indoors with non-vigorous physical movement. The school will also take into consideration recommendations and/or mandates from the Colombia Ministry of the Environment, the Mayor’s office, or the Secretary of Education.

Families will be notified of this decision based on poor air quality. CNG will also inform parents and staff in advance if the school must take a decision to schedule an early release and/or switch to virtual learning if air quality drops to a Very Unhealthy or Hazardous level.

Reference Resources for CNG’s AQM Policy and Protocols: The Colombian Ministry of the Environment, Índice Bogotano de Calidad del Aire y Riesgo de Salud (IBOCA), the U.S. Environmental Protection Agency, and policy documentation from Shanghai American School, the International School of Kuala Lumpur, Concordia International School, the International School of Tianjin, and the International School of Beijing.

Colegio NUEVA GRANADA | | Cra 2E No. 70-20 | Phone: (571)212 3511
Bogotá - Colombia