Carbon monoxide is often called the "silent killer." Many people are aware of this threat and have detectors in their homes to alert them to the presence of this deadly gas. But in this post, we’re focusing on another hazardous gas, carbon dioxide, or CO2.

So first up, what is CO2 exactly?

Carbon dioxide is a heavy, odorless, colorless, faintly acid-tasting, and non-flammable gas (at room temperature) that is released during respiration, combustion, and by the decomposition of organic substances.”

Most people think of outdoor air pollution when they think of CO2. So you’re probably picturing smoke stacks or car exhausts filling the air with noxious black smoke. But increased CO2 inside is also a big deal; after all, we spend almost 90% of our lives indoors. So when it comes to monitoring indoor air quality (IAQ) for CO2, data loggers can be a great safety measure.

Increased CO2 Inside - Why Should You Care?

  • Tight-building standards increase risk of sick-building syndrome and poor occupant health
  • Offices, schools, healthcare facilities, gyms, and homes frequently exceed healthy CO2 levels
    • Buildings where metabolic rates are high—gyms, fitness centers, and aerobic-workout rooms—frequently exceed acceptable standards (breathe in O2, breathe out CO2)
  • Indoor CO2 concentrations over 1,000 ppm lead to cognitive impairment and dysfunction
  • Global CO2 exposure limits vary by country; some countries have much more stringent restrictions than US standards



“At certain times of the year, when inside-outside temperature differentials are large, windows may be shut to conserve energy, promoting high CO2 concentration and trapping unhealthful indoor pollutants. As a result, marginal or poor indoor-air quality is commonplace in conference rooms, auditoriums, school classrooms, healthcare facilities, and residential dwellings.” – Read the white paper.



What Can You Do? A Data Logging Solution:

“CO2 data loggers provide a cost-effective method to assess indoor air quality, helping to eliminate sick-building syndrome and harmful pollutants typical of tight and poorly ventilated structures.”

Want to monitor CO2, but don’t know where to start? Check out this free guide:

Managing Carbon Dioxide Risk; What You Should Know







Want more on Indoor IAQ? Check out, How Badly Is IAQ ‘Killing You Softly’

Are you using the HOBO CO2 Data Logger to monitor indoor CO2 levels? We’d love to hear about it! Email us at

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