Monitoring carbon dioxide (CO2) levels is important. It helps to ensure the air quality in any given environment is safe and healthy to breathe. High CO2 levels indicate poor ventilation, and can lead to a variety of health issues.
Below are the most common frequently asked questions about CO2 monitoring our customers ask.
What is a CO2 Monitor?
A CO2 monitor is a device that displays or transmits the amount of carbon dioxide gas by volume in the surrounding air. CO2 monitors may be handheld or desktop with a display, or can be permanently installed with electronics to activate an alarm if CO2 levels exceed a programmed threshold. Some display CO2 levels in real-time while some store CO2 levels in memory to graph changes over time.
CO2 monitor price ranges from under $100 dollars to thousands of dollars depending on features and accuracy.
Why are CO2 Monitors used?
Monitoring CO2 levels for indoor air quality is important because high levels of CO2 can cause headaches, fatigue, dizziness, and nausea in an enclosed room. In addition, high CO2 levels indoors is an indicator of poor ventilation which can result in a buildup of other indoor air pollutants such as dust, mold, volatile organic compounds (VOCs), airborne bacteria and viruses.
In businesses that use tanks or cylinders of compressed CO2, monitors serve as alarms to warn room occupants of potentially deadly CO2 leaks.
Where are CO2 Monitors used?
- CO2 monitors are used in homes, offices, classrooms and vehicles to measure CO2 levels as an indicator of total indoor air quality.
- They are used in restaurants, indoor greenhouses and factories that use tanks or cylinders of compressed CO2 to warn workers of a CO2 leak.
- They are used by underground workers, in tunnels and caves to monitor for high CO2 levels leaching from the soil.
- They are used in breweries to protect workers inside or near fermentation vessels.
- CO2 monitors are used outdoors to monitor carbon dioxide levels over time in outdoor air for climate scientists.
How does a CO2 Monitor work?
CO2 is measured using a carbon dioxide sensor. The sensor measures the concentration of carbon dioxide in the air and provide real-time readings.
Modern CO2 sensors use non-dispersive infrared (NDIR) technology The sensors detect the absorption of infrared light at a wavelength equal to the size of a CO2 molecule in a sample of air. The amount of infrared light measured is proportional to the number CO2 molecules in the air. The monitor then displays the CO2 levels in parts per million (ppm) on a screen, in an application, or sends it to another device that controls an alarm system.
Learn how an NDIR CO2 sensor works here.
What is the ideal CO2 level?
The ideal CO2 level is between 400 ppm and 800 to 1,000 ppm indoors. 400 ppm is considered "fresh air."
The American Society of Heating, Refrigeration and Air Conditioning Engineers (ASHRAE) has historically recommended that indoor carbon dioxide levels be maintained below 1,000 ppm in schools and 800 ppm in offices.
However, because CO2 levels outdoors varies widely, ASHRAE now recommends that indoor CO2 levels should not be more than 700 ppm above outdoor air levels. For example, in a city the outdoor CO2 levels might be 600 ppm, so the ideal CO2 level would be no more than 1,300 ppm (600 + 700 ppm) in an office.
What factors affect CO2 levels?
In an industrial environment or anywhere tanks or cylinders of CO2 are used, the major factor is proximity to the stored CO2. The closer you are to a potential leak, the higher the risk of elevated CO2 levels.
In homes, schools and office buildings, factors that affect CO2 levels indoors include:
- The number of occupants in the room
- The duration of occupancy
- The size and ventilation of the room
- Activities performed in the room (e.g., cooking, exercising, smoking)
- Outdoor air quality
In general, CO2 levels tend to higher in poorly ventilated, crowded, or confined spaces.
What are the potential health effects of high carbon dioxide levels?
High levels of carbon dioxide can lead to symptoms such as headaches, fatigue, dizziness, and nausea. Prolonged exposure to high levels of carbon dioxide can also lead to more serious health issues, such as respiratory problems.
How can I stay safe around CO2?
To stay safe from high CO2 levels indoors it is important to ensure the area is well-ventilated. In areas where CO2 is stored in tanks or cylinders it is important to have carbon dioxide monitoring equipment.
Additionally, it is important to follow all safety procedures and necessary guidelines when working with CO2. Read our whitepaper: Standard Operating Procedures of Gas Monitors by Industry.
What is the OSHA limit for carbon dioxide exposure?
The Occupational Safety and Health Administration (OSHA) is one of many organizations that have recommended exposure limits for CO2.
You can read all the codes here.
How do I know which CO2 code or regulation to meet?
Ask your local fire inspector to provide details about the specific code you are being asked to meet. Typically, it will be a local code, the International Fire Code, the National Fire Protection Association code, or the National Board Inspection Code.
The codes are similar but do have some specific requirements you may need to be aware of. You can always contact CO2Meter.com for assistance in deciphering your code requirements.
Where to mount a CO2 Monitor?
Different applications allow for different coverage areas.
• Offices, Classrooms
Each room should have its own CO2 monitor typically mounted 4-5 feet above the floor.
• Beverage Production, Factories
The International Fire Code calls for the device/sensor to be mounted 12 inches off the floor. Some jurisdictions may allow for different heights depending on obstructions or use cases. For further information, please consult your local fire inspector.
Monitors can cover approx. 1,500 sq. feet (length x width of the space). Typically, placement within 10 feet of a bulk CO2 storage tank or cylinder is sufficient.
• Larger spaces may require additional monitors
Enclosed rooms or spaces (closets, offices, bathrooms, and keg coolers) may require additional monitoring as gas can be trapped in these spaces because of the enclosure.
• CO2 Enriched Areas
Applications where CO2 is intentionally injected into a space (i.e. CO2 enrichment) like indoor greenhouses allow for larger coverage areas because of the continuous circulation of the air. In these applications a monitor can effectively cover less than 2,000 sq. feet (length x width of the space).
See our gas sensor mounting height chart here.
My bulk tanks are outdoors. Do I still need a CO2 monitor?
Outside storage of tanks and cylinders is allowed by the code and the manufacturers of these storage vessels.
However, the gas is being used INSIDE the facility and a monitor will be required at the “first point of use” inside. This is typically at the BIB rack or carbonator. Since leaks often happen near gas tube connections, it makes sense to place a monitor near a manifold where multiple CO2 gas lines converge.
What are the alarm settings for a CO2 Safety Monitor?
When it comes to carbon dioxide safety, a typical CO2 safety monitor should come configured with alarms that meet the specific NFPA, IFC, and NBIC code requirements. These alarm settings are as follows:
- Alarm 1 – pre-set to 5,000 ppm TWA. Time Weighted Average is a rolling 8-hour average designed to measure someone’s exposure over an 8-hour work cycle. This is an OSHA requirement. Alarm 1 cannot be altered.
- Alarm 2 – pre-set to 15,000 ppm or 1.5% CO2.
- Alarm 3 – pre-set to 30,000 ppm or 3.0% CO2.
Please note, some jurisdictions have asked for different alarm set points. For example, the International Fire Code calls for the first alarm at 5,000 ppm, not a TWA. While CO2Meter does not recommend these alterations to the OSHA set points they can be requested.
How often should I calibrate my CO2 monitor?
The frequency of calibration depends on the type and model of the CO2 monitor, as well as the manufacturer's recommendations. the calibration interval can be anywhere from daily for personal protection devices to no calibration required for monitors that use Automatic Baseline Calibration. It is important to follow the manufacturer's instructions and replace the sensors or recalibrate the device as needed to ensure accurate readings.
Learn more about CO2 sensor calibration here.
What should I do if I suspect a CO2 leak?
If you suspect a CO2 leak, leave the area immediately and alert others to do the same. Call emergency services and report the leak. Do not attempt to stop the leak or investigate the source of the leak yourself.
As a reminder, precautions should always be followed when working near any compressed gases like CO2 in the workplace. Because hazards of CO2 can occur quickly, your establishment should always know what to do should a potential leak occur and have the proper co2 monitors in place to prevent injury in the workplace.
What is the best CO2 Monitor?
There are several factors that one should take into consideration when selecting the right carbon dioxide safety monitor.
For home office or classroom use, we recommend the TIM10 Desktop CO2 Monitor. It is accurate, inexpensive, has a long lifespan, is self-calibrating, and is proven with tens of thousands in use.
For CO2 safety monitoring, various partners, customers, and industry leaders have all looked at critical features such as the following:
- Safety Alarms that meet OSHA set points
- Active Relays that can trigger third party systems
- Large LCD Display
- UL Listed
- Meets State Fire Codes for Compliance
- Ease of Use and Installation
- Durability
- Expandability
When it comes to providing individuals with the right features to protect and safeguard employees, staff, and establishments - the Remote CO2 Storage Safety 3 Alarm is an ideal choice.
This device provides users audible and visual alarms notifying personnel that a hazard is occurring. It also can activate relays and trigger third party systems like ventilation, fire panels, or building management/security systems should CO2 levels reach a higher than normal threshold. The device also meats code compliance and workplace exposure limits.
Many food and beverage franchises, restaurants, bars, breweries, and indoor agriculture farms report its ease of use, 30-minute installation process and low price.
For more information on carbon dioxide monitoring, contact us today.