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Facility Ventilation Search Engine

Find out the ventilation levels in your facility now.


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Our mission is to

organize the world’s facility ventilation information and make it universally accessible and useful,

and offer in Room Ventilation Alarm products.

We gather

user observations when they visit facilities,

import site survey data from facility managers,

import Government certified data from sources like schools and test labs,

we do our own research to find facility ventilation data already on the web,

and we connect our ventilation alarm products to F V S E.

We present data in a variety of ways

building summaries, room details, groups of buildings statistics, reports, certificates, etc

using various views meant to convey the most essential information as quickly as possible.

Our in room ventilation alarm products

alert occupants when there are problems

and they continuously send data to F V S E.

click and see views

It all starts with a F V S E query.


Our Vision

  1. Make everyone aware of ventilation performance levels using official industry terms - Air Changes Per Hour or ACH or eACH.
  2. Disclose the ventilation performance levels in terms of ACH or eACH levels, everywhere.
  3. If the ventilation level drops below a certain ACH or eACH level, generate alarms in affected rooms, in the same way that smoke detectors generate alarms to alert occupants to fire hazards.

Our facility ventilation systems started to fail us slowly with the start of the energy crisis in the 1970's. As time moved on it just became worse and it is not getting better. This is a  long term problem. It is not going away. We have the technologies, we know what to do, this is a social problem. Only you can make this final vision of safe ventilation levels in our buildings, planes, trains, busses, and other spaces.

Start using F V S E today.

Add your observations.

Reach out to your schools and places of work and ask them to provide data for F V S E.

Contact us about our Ventilation Alarm products that alert occupants to ventilation problems.

It all has to start somewhere and this is the place and the time.


Ventilation Basics

A building ventilation system is a life support system.

If the ventilation is not working properly people will be infected by airborne contagions.

Ventilation performance is key to ensure that the risk of infection is minimized or eliminated in a room.

Ventilation is measured in terms of Air Changes per Hour (ACH) or Equivalent (eACH) for UV based systems.

If the ACH is zero or 1 we know that people including children in schools will be infected by an airborne contagion.

As the ACH level increases the risk of infection drops.

For hospital rooms with airborne contagions the CDC recommends a minimum of 12 ACH.

The Heating Ventilation and Cooling (HVAC) systems and UV systems are the primary approaches used to ventilate buildings.

Many  buildings have poor maintenance with closed off vents, failed fans, or poor operations where the system is turned off when people are present.

Many  buildings have systems that are too small.

The Facility Ventilation Reporting service allows people to take control of their environments and examine the ventilation rates of the buildings that they visit.

Anyone can add buildings to the database if there is no data.

The CAB data is a summary of a facility.

The ACH data (including eACH) has multiple rooms found in a facility.

The data currently is based on visitor observations and site surveys some of which is Certified by Government authorities.

In the future, there will be real time data providing the latest ventilation status.

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How to start: Just start pressing the buttons above.


Why should facility occupants participate

  1. Occupants are alerted to ventilation problems just like smoke detectors alert occupants to fire hazards.
  2. Social media and crowdsourcing ventilation data will significantly help to deal with airborne contagion risk.

Why should facilities disclose their ventilation data in the public database

  1. All things being equal, people and companies will avoid facilities that will not disclose their ventilation data.
  2. Occupants want to know and they have a right to know the ventilation levels in the facilities they visit.

Why should facilities install the new Ventilation Alarms System

  1. Sensors are right at the interface vent rather than down stream giving accurate real time ventilation data for each room to ensure the building is properly balanced and not wasting energy.
  2. Sensors today are for a zone and a zone typically serves multiple rooms, someone may have closed the vents in a room, with no indication of the serious problem.
  3. Sensors today do not alert occupants to ventilation problems, they only alert maintenance staff.
  4. Accurate data is available for labs that must prove via documented evidence the ventilation levels needed for certification in a room.
  5. Costly site surveys with poor and old data results are no longer needed.
  6. Employers have real data that they properly responded to the ventilation problems that the COVID-19 disaster surfaced.
  7. Building owners can use this as a fact based value discriminator to increase occupancy rates and bring people back into empty offices.
  8. All things being equal, early adopters will attract greater revenues when companies and people decide which facilities they will pick.
  9. Self insured employers will have reduced health care costs.
  10. Over 1 million people died and the country was shut down for almost 2 years. It is clear that we must not allow our facilities to cause another airborne infection disaster ever again.
  11. There is much more that we uncovered to justify investment in this system.

Still hesitant...

Learn More: Building Ventilation

Deep Learning: Clean Air Buildings


What can I do Now?

The following are guidelines for people visiting a facility.

  1. Listen to determine if the ventilation is on. If you can't hear it tell the staff it is stuffy and to turn on the ventilation.
  2. In a clubhouse setting, when you enter a room, check the thermostat. If the Fan is off, turn it on even if the system sounds like it is running. It is probably just adjusting temperature.

The following are general guidelines for optimizing the ventilation performance level in any facility.

  1. Turn on the ventilation system 1-2 hours before occupants arrive.
  2. Do not immediately turn off ventilation system after occupants leave, wait 1-2 hours.
  3. Replace batteries in thermostats so that displays are always visible.
  4. Fix any broken fans so that they operate.
  5. Make sure vents are not blocked and have a 6 foot clearance.
  6. Open any closed dampers and vents because of previous complaints of hot or cold air.
  7. Adjust or change vent types so that there are no complaints but keep the vents open.
  8. Post signs to turn on the system fans and provide simple instructions.
  9. Post certificates at each thermostat showing last maintenance date and average ACH level.
  10. Place streamers on all the vents to show that the system is running.
  11. Fix areas that have zero and low ACH ventilation readings.
  12. Consider adding ceiling level / upper room UV-C lights or FAR UV-222 lights.
  13. Ensure filters are clean and do not restrict airflow.
  14. Place an anemometer in each room and let staff measure ventilation rates as part of a daily routine.
  15. Submit the ventilation site survey data to the Facility Ventilation Search Engine (FVSE) for rating and comparison.




Facility Types

Many buildings have poor maintenance with closed off vents, failed fans, or poor operations where the system is turned off when people are present. Many buildings are not being operated properly. The systems are turned off when the public is present. This is especially found in buildings like club houses with on demand systems. No one is turning ON the fan option when people are present. Many  buildings have systems that are too small. The reality is that there are Elite buildings where everything is properly maintained, operated, and they have high ACH levels exceeding 12+ ACH.

Facility Type ACH Levels Maintenance Operations
Elite Facilities Excellent Excellent Excellent
Medium Facilities Lower Excellent Excellent
Low End Facilities Lower Poor Excellent
Low End Facilities Lower Excellent Poor
Low End Facilities None Poor Poor

Where does your facility fall?



FVSE Search Rating Scales

The FVSE search rating scales take the ACH levels and apply them to a rating level that provides a text based rating and a color assignment. The rating scales are named as follows:

The Airborne scale is based on the CDC guideline of 12+ ACH for airborne contagions. The scale is divided by each increment of ACH 0, 1, 2, 3… up to 15 ACH. A rating and color is assigned to each level. The green level starts at 12 ACH. This is a FVSE scale based on Cassbeth research.


Airborne Scale

Airborne Scale


Very Low 0-1



Low 2-5



Med 6-11



Elite 12-15


The Comfort scale is from the Harvard T.H. Chan School of Public Health: Schools for Health: 5-step guide to checking ventilation rates in classrooms. It is considered a low end scale because the CDC guideline for airborne contagions is 12+ ACH and this scale reaches a green level at 5+ ACH. This scale has a higher risk of airborne infections than a scale based on the CDC guideline of 12+ ACH. This scale is driven by the reality of the existing ventilation infrastructure. It is based on comfort levels not airborne contagion mitigation.


Comfort Scale

Comfort Scale

< 3




Bare Minimum







Light Green




The Outdoors Comparison scale is based on the ACH levels that are found in outdoor settings. The scale rates ACH levels against the ACH levels available in outside scenarios. These ACH levels are extremely high and very healthy where the infection risk is very low. The green level starts at 50+ ACH. In the ideal situation this is where ventilation needs to go in the 21st century. The goal is to bring the outside ACH inside with no compromises. The reality is there are Green ventilation level rooms with an Outdoor rating today in many buildings but they are special cases. This is a BCMC scale based on Cassbeth research.


Scale Rating

Scale Color


Bad 0



Low 1



Med 2



High 3



Very High 4



Outdoor 5



Outdoor 6



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