Short answer
Prioritize ventilation and air quality monitoring in educational space design to combat student sleepiness and enhance learning.
- Field
- Human Factors
- Source
- Sustainability (2025)
- Method
- Experimental pilot study
- Sample
- 27 participants
- Evidence
- Strong effect
Poor indoor air quality, specifically high concentrations of carbon dioxide (CO2), is directly linked to increased student sleepiness during learning periods. This human factors research insight is drawn from a 2025 study published in Sustainability. Using Experimental pilot study with 27 participants, researchers explored how this design variable affects real-world outcomes. The key design takeaway: Prioritize ventilation and air quality monitoring in educational space design to combat student sleepiness and enhance learning.
Elevated CO2 levels in classrooms significantly increase student sleepiness
Poor indoor air quality, specifically high concentrations of carbon dioxide (CO2), is directly linked to increased student sleepiness during learning periods.
Sustainability · 2025
Key Findings
- 01Student sleepiness significantly increased during the school period across all three measurement days.
- 02The increase in sleepiness was associated with high indoor CO2 concentrations (ranging from 978 to 3261 ppm), indicative of reduced ventilation rates.
- 03Sleepiness increased regardless of perceived thermal comfort or airborne particle concentrations.
Application
Design takeaway
Prioritize ventilation and air quality monitoring in educational space design to combat student sleepiness and enhance learning.
How to apply
When designing or retrofitting educational spaces, specify ventilation systems capable of maintaining CO2 levels below 1000 ppm and consider integrating CO2 sensors for active management.
Project actions
- 01Consider measuring CO2 levels in your design space.
- 02Investigate different ventilation strategies and their impact on air quality.
Method & Evidence
Variables
Strengths & Limitations
Strengths
- +Directly measured IEQ parameters.
- +Used a validated sleepiness scale (ESS).
Limitations
The study's findings might not apply to all age groups or different types of learning environments. The duration of exposure to high CO2 levels was limited to school hours.
Reliability & validity
The use of objective IEQ measurements and a standardized sleepiness scale enhances reliability. However, the pilot nature and small sample size may limit generalizability and external validity.
Think critically
How might the duration of exposure to elevated CO2 levels influence the severity of sleepiness and its impact on learning?
Design Principles
"Optimize indoor air quality to support cognitive function and well-being."
This finding highlights a critical, often overlooked, environmental factor impacting cognitive function and learning outcomes. Designers and educators must consider IEQ as a primary driver of student engagement and well-being, moving beyond traditional pedagogical approaches.
What This Means for Your Design
When classrooms don't have enough fresh air, the CO2 level goes up, making students feel tired and sleepy during lessons.
How to use in your project
- 1.Use this research to justify the importance of IEQ in your design project.
- 2.Cite the findings to support your design decisions related to ventilation or air quality.
Add to My Project
Quick Cite
Paragraph starter
This study demonstrates a significant link between elevated CO2 concentrations in classrooms and increased student sleepiness, highlighting the critical role of adequate ventilation in maintaining optimal learning conditions. The research indicates that poor indoor air quality directly impairs cognitive function, suggesting that design interventions focused on ventilation and air quality management are essential for creating effective educational environments.
Source
Sustainability
Assessment of Indoor Classroom Environment Quality Associated with Student Sleepiness: Pathways Towards a Sustainable Environment Through a Pilot Study
journal · 2025
View sourceQuestions About This Research
- What does the research say about elevated co2 levels in classrooms significantly increase student sleepiness?
- Prioritize ventilation and air quality monitoring in educational space design to combat student sleepiness and enhance learning. Evidence: Sustainability (2025).
- Why does "Elevated CO2 levels in classrooms significantly increase student sleepiness" matter for design?
- This finding highlights a critical, often overlooked, environmental factor impacting cognitive function and learning outcomes. Designers and educators must consider IEQ as a primary driver of student engagement and well-being, moving beyond traditional pedagogical approaches.
- How can designers apply this research?
- Prioritize ventilation and air quality monitoring in educational space design to combat student sleepiness and enhance learning.
- What were the main findings?
- Student sleepiness significantly increased during the school period across all three measurement days.. The increase in sleepiness was associated with high indoor CO2 concentrations (ranging from 978 to 3261 ppm), indicative of reduced ventilation rates.. Sleepiness increased regardless of perceived thermal comfort or airborne particle concentrations.
- What research method was used?
- Experimental pilot study with 27 participants.
- How strong is the evidence?
- Evidence strength is rated Strong effect, based on a 2025 journal from Sustainability.
- What should I do differently in my next project?
- When designing or retrofitting educational spaces, specify ventilation systems capable of maintaining CO2 levels below 1000 ppm and consider integrating CO2 sensors for active management.
- What are the limitations?
- This was a pilot study with a small sample size and was conducted in a single classroom, limiting generalizability. The study did not isolate the effect of CO2 from other potential environmental or behavioral factors.