Short answer

Designers can confidently design spaces with CO2 levels up to 2100 ppm without expecting a significant negative impact on cognitive function in adults, allowing for more flexible ventilation strategies.

Field: Human Factors
Source: Building and Environment (2023)
Method: Controlled laboratory experiment
Sample: 69 participants
Evidence: Mixed findings

Contrary to some assumptions, short-term exposure to pure carbon dioxide levels up to 2100 ppm did not negatively impact cognitive performance or health symptoms in healthy adults. This human factors research insight is drawn from a 2023 study published in Building and Environment. Using Controlled laboratory experiment with 69 participants, researchers explored how this design variable affects real-world outcomes. The key design takeaway: Designers can confidently design spaces with CO2 levels up to 2100 ppm without expecting a significant negative impact on cognitive function in adults, allowing for more flexible ventilation strategies.

Study

Human FactorsRecentMixed findings

Elevated CO2 Levels Up to 2100 ppm Do Not Impair Cognitive Performance in Adults

Contrary to some assumptions, short-term exposure to pure carbon dioxide levels up to 2100 ppm did not negatively impact cognitive performance or health symptoms in healthy adults.

Building and Environment · 2023

Key Findings

01No significant differences in cognitive performance accuracy were found across the tested CO2 levels.
02Response times improved in two out of ten cognitive tests at 1500 ppm compared to 600 ppm.
03Air quality was rated higher at 1500 ppm than at 600 ppm, but not at 2100 ppm.
04No significant differences were observed in thermal sensation, perceived lighting quality, perceived noise level, or health symptoms.

Application

Design takeaway

How to apply

When designing or retrofitting spaces, consider that CO2 levels up to 2100 ppm are unlikely to hinder cognitive tasks for adults. Prioritize other environmental controls if cognitive performance is a key objective.

Project actions

01Consider the specific context of your design project: is it for adults, children, or a mixed group?
02When measuring environmental factors, ensure your equipment is calibrated and appropriate for the pollutants you are investigating.

Method & Evidence

AimTo investigate the effects of short-term exposure to moderate pure carbon dioxide levels (600, 1500, and 2100 ppm) on cognitive performance, health symptoms, and perceived indoor environment quality in healthy adults.

MethodControlled laboratory experiment

ProcedureParticipants were individually exposed to three different CO2 concentrations (600, 1500, and 2100 ppm) for 70 minutes each in a crossover design. Cognitive performance was assessed using a validated neurobehavioral test battery, and subjective ratings of the indoor environment and health symptoms were collected via questionnaires.

Sample69 participants

ContextControlled environmental chamber simulating indoor educational building conditions

Variables

IVCarbon dioxide (CO2) concentration levels (600 ppm, 1500 ppm, 2100 ppm)

DVCognitive performance (response time, accuracy), perceived indoor environment quality, health symptoms

CVVentilation rates, temperature, humidity, lighting, noise levels, participant health status

Strengths & Limitations

Strengths

+Controlled experimental environment ensures high internal validity.
+Crossover design minimizes individual differences as a confounding factor.

Limitations

The study used pure CO2, which might not reflect real-world indoor air conditions. The duration of exposure was short.

Reliability & validity

The use of validated tests and a controlled environment enhances reliability and internal validity. However, the artificial nature of the CO2 exposure and the short duration might limit external validity.

Think critically

Given these findings, what other indoor environmental factors might be more critical for optimizing cognitive performance in educational buildings?

Design Principles

"Environmental factors should be assessed for their actual impact on human performance and well-being, rather than relying solely on perceived risks or outdated guidelines."

This research challenges the common perception that elevated CO2 is a primary indoor air pollutant affecting cognitive function. Designers and engineers can re-evaluate ventilation strategies and focus on other environmental factors that may have a more significant impact on occupant well-being and productivity.

What This Means for Your Design

Breathing air with higher CO2 levels (up to 2100 ppm) didn't make people dumber or sicker in a short test, and sometimes even made them react a bit faster.

How to use in your project

1.Reference this study when discussing the impact of indoor air quality on cognitive function, particularly if your design aims to improve user performance.

Add to My Project

Quick Cite

Paragraph starter

Research by Chen et al. (2023) found that short-term exposure to CO2 levels up to 2100 ppm did not negatively affect cognitive performance or health in adults, suggesting that CO2 may not be the primary pollutant to address for cognitive enhancement in educational settings.

Source

Building and Environment

Effects of short-term exposure to moderate pure carbon dioxide levels on cognitive performance, health symptoms and perceived indoor environment quality

journal · 2023

View source

Questions About This Research

What does the research say about elevated co2 levels up to 2100 ppm do not impair cognitive performance in adults?: Designers can confidently design spaces with CO2 levels up to 2100 ppm without expecting a significant negative impact on cognitive function in adults, allowing for more flexible ventilation strategies. Evidence: Building and Environment (2023).
Why does "Elevated CO2 Levels Up to 2100 ppm Do Not Impair Cognitive Performance in Adults" matter for design?: This research challenges the common perception that elevated CO2 is a primary indoor air pollutant affecting cognitive function. Designers and engineers can re-evaluate ventilation strategies and focus on other environmental factors that may have a more significant impact on occupant well-being and productivity.
How can designers apply this research?: Designers can confidently design spaces with CO2 levels up to 2100 ppm without expecting a significant negative impact on cognitive function in adults, allowing for more flexible ventilation strategies.
What were the main findings?: No significant differences in cognitive performance accuracy were found across the tested CO2 levels.. Response times improved in two out of ten cognitive tests at 1500 ppm compared to 600 ppm.. Air quality was rated higher at 1500 ppm than at 600 ppm, but not at 2100 ppm.. No significant differences were observed in thermal sensation, perceived lighting quality, perceived noise level, or health symptoms.
What research method was used?: Controlled laboratory experiment with 69 participants.
How strong is the evidence?: Evidence strength is rated Mixed findings, based on a 2023 journal from Building and Environment.
What should I do differently in my next project?: When designing or retrofitting spaces, consider that CO2 levels up to 2100 ppm are unlikely to hinder cognitive tasks for adults. Prioritize other environmental controls if cognitive performance is a key objective.
What are the limitations?: The study focused on short-term exposure and healthy adults; long-term effects and impacts on vulnerable populations may differ. The CO2 was pure CO2, not representative of typical indoor air mixtures.