Carbon Dioxide (CO2)

Carbon Dioxide occurs naturally in the atmosphere (380-400ppm) and is a by-product of human, animal and plant respiration and combustion of fossil fuels.

Its measurement can be used as an early indicator of deteriorating air quality within the built environment. Examples being, commercial kitchens and teaching areas in education buildings.

It is also used commercially in laboratories, extinguishers and the drinks and leisure industry.

The cause of CO₂ and the environment it’s being detected within will have impact on the height, level and outcome with Medem providing individually designed solutions for each environment.

Oxygen depletion detectors should never be used to monitor for CO₂.

Long term exposure limit (8hours TWA) 5,000ppm. Short term exposure (15 minutes) 15,000ppm with additional specific targeted alarm levels for education and commercial kitchens.

Education

There are legislation and design standards based around the required quality of ventilation levels for teaching spaces.
These are for monitoring comfort levels for occupation as set out in Building Bulletin 101 and when monitoring for the consideration of risk with IGEM UP11 when gas appliances are being used. Both of these documents have recently been updated to provide the latest guidelines on allowable CO₂ levels.

Related Products: GPPS-evo & SEC-L

Catering

Due to the use of open flame appliances, it was identified that CO₂ levels would change rapidly in a commercial kitchen highlighting Inadequate ventilation or blocked filters. The CO₂ level is also used within the catering industry as a guide to good air quality conditions covering temperature and humidity. With an increased CO₂ level, custom and practice have determined that the workplace becomes uncomfortable. In summary CO₂ monitoring is a true indication of the ventilation performance and cooking load. It allows for the impact from occupation and seasonal variations to be considered.

Related Products: VGPS-evo & SEC-K

Commercial

Unlike in education and catering where CO₂ is primarily created by the burning of gas and from occupancy, in the commercial sector CO₂ can be in relation to bottled CO₂ which present a different set of risks and considerations. Bottled CO₂ is heavier than air, it will tend to concentrate at floor level and will disperse throughout the available floor area which could prove hazardous if not identified. Cellars and CO₂ bottle stores in pubs and restaurants are just one area this has been identified with.

Related Products: AGDS-M, AGDS-MCM v2 & AGDS-elite

Frequently Asked Questions

At what height should Carbon Dioxide (CO₂) gas detectors be installed?

According to guidance from IGEM/UP11, classroom CO₂ detectors should be mounted at seated head height. However, based on on-site experience, this mounting height can make detectors susceptible to false readings due to direct breath contact.

An Option:

To reduce the potential for false alarm readings, following the guidance for mounting CO₂ detectors as per commercial kitchens, placing them above standing head height to minimise direct breath influence.

Commercial Kitchen CO₂ Detectors:

In commercial kitchens, CO₂ detectors should be installed to monitor the general level of CO₂ within the kitchen operatives working areas.

Height and Positioning: These detectors should be mounted between 1 and 3 meters from the cooking line, above standing head height. Care should be taken to avoid placing them close to the edge of a canopy or in direct flow from supply or extract ventilation systems, as this can affect their performance.

Laboratory CO₂ Detectors (Piped or Bottled):

For laboratories using piped or bottled CO₂, detectors should be positioned to monitor the most likely points of leakage, such as gas taps, regulators, and bottle storage areas.

Height Placement: Since CO₂ is heavier than air, detectors should be installed at low levels to ensure accurate detection of any potential leaks.
Key Considerations: Regular inspection and testing of these detectors are crucial to maintain safety and ensure they are effectively monitoring for leaks.

How many Carbon Dioxide (CO₂) gas detectors should be installed?

The number of carbon dioxide (CO₂) gas detectors needed depends on several factors such as the size of the area, ventilation, and the potential sources of CO₂ emissions. Here’s a general guide to help determine how many detectors you might need:

Key Considerations:

Room Size and Layout: Larger spaces may require multiple detectors to ensure coverage, especially if the room has separate sections or obstacles like walls.
Potential CO₂ Sources: Detectors should be placed near potential CO₂ sources, such as HVAC systems, combustion equipment, or enclosed spaces where CO₂ can accumulate, such as commercial kitchens, laboratories, breweries, or indoor agricultural spaces.
Occupancy: In areas with high occupancy, such as offices, classrooms, or commercial spaces, it is advisable to install more detectors to monitor CO₂ levels related to human respiration.

Is Carbon Dioxide (CO2) gas lighter or heavier than air?

Carbon dioxide (CO₂) is heavier than air. Its relative density compared to air is about 1.5, meaning it tends to settle in lower areas when released, especially in enclosed or poorly ventilated spaces. Because of this, CO₂ detectors are typically installed lower to the ground or at specific heights depending on the application and location see above guidance re:CO2 as a by-product of combustion or respiration.

Is Carbon Dioxide (CO2) gas a greenhouse gas?

Carbon dioxide (CO₂) is a significant greenhouse gas. It plays a major role in trapping heat in the Earth’s atmosphere, contributing to the greenhouse effect and global warming. CO₂ is released through natural processes like respiration and volcanic activity, but human activities such as burning fossil fuels, deforestation, and industrial processes have significantly increased its concentration in the atmosphere, leading to climate change.

While CO₂ is not the most potent greenhouse gas, it is the most abundant one produced by human activities, making it a key factor in global climate regulation.

Not finding the answer you’re looking for? Feel free to contact us at technical@medem.co.uk, and we’ll be happy to assist you.