Monitoring CO2 Levels Indoor
It is important to monitor CO2 levels because they directly influence the mood, productivity, and health of those exposed to CO2. Incorrect CO2 levels can cause stiffness, odours, drowsiness, and reduced productivity. Higher levels, or prolonged exposure, can be very harmful to health.
High CO2 levels can be an indication that there is a lack of fresh air in the space.
The indoor CO2 level depends on : The number of people present How long that space has been occupied - The amount of outdoor fresh air entering and other factors. The main cause of Carbon Dioxide indoors is people. The more people in an area, the more CO2 is emitted. Respiration of humans introduces this CO2. The amount emitted from one working person can be from 0.08m2 to 0.38m2 per hour, depending on the intensity of their work.
Carbon dioxide concentrations in indoors can vary from several 100 parts per million to over 1,000 ppm in areas with many people present for an extended period and where fresh air ventilation is limited. Due to COVID 19 concerns, it is recommended that Co2 Levels should not increase more than 700 PPM.
CO2 concentrations in closed or confined rooms can increase to 1,000 ppm within 45 minutes. For example, in a 3.5-by-4-metre (11 ft × 13 ft) sized office, atmospheric CO2 increased from 500 ppm to over 1,000 ppm within 45mins of ventilation cessation and closure of windows and doors.
When CO2 levels are elevated in the body it is known as hypercapnia. Hypercapnia can occur for several reasons, one of which is rebreathing our own exhaled CO2. Rebreathing CO2 can lead to increased blood pressure, headaches, muscle twitches, rapid heart rate, chest pain, confusion, and fatigue. In extreme cases, if left untreated, it can lead to organ damage and even have long-standing effects on the brain.
Regular replacement of air filters and installing CO2 monitors can help in mitigating indoor levels of CO2.
CO2 Levels are measured as PPM (Parts Per Million). The standard outdoor level is around 350ppm, and is the optimum level for freshness. However, you can generally get up to 600ppm indoor without any adverse effects. As you can see in this chart, once you get past 600ppm you will start noticing adverse effects.
CO2 levels have a noticeable impact on one's productivity and wellbeing. The higher the levels, the lower the productivity. The lower the levels, the better one can work. Therefore it's important to measure and constantly conduct CO2 Monitoring within your workplace.
Here are some practical steps to lowering your CO2 and ensuring it stays low:
· Increase ventilation from outdoors This is the big one and is key to reducing CO2 levels indoors is proper ventilation. Outdoor CO2 levels should be below 400ppm, so ensuring more fresh outside air is brought indoors is the key to lowering your Carbon Dioxide.
· Check and maintain your HVAC (Heating, Ventilation and Air Conditioning) System Some offices are sealed very well, which is good for energy efficiency in your HVAC system as it doesn't need to cool hot air often. However, it means you have very little fresh air coming in and the CO2 levels will just keep building. Other systems will actively bring in air from an outside vent and mix it with the inside air – this is preferred as it is constantly lowering your indoor CO2 levels.
· Check gas devices for leakage and cross ventilation Leaking gas devices can cause the CO2 level to rise. Preferably get the device repaired or replaced so it doesn't continue to leak. Failing this, open a window on the opposite side of the room to allow for cross ventilation.