Experimental study on sleep quality affected by carbon dioxide concentration

Xu, Xinbo; Lian, Zhiwei; Shen, Jingyun; Cao, Ting; Zhu, Jingwen; Lin, Xiang; Qing, Ke; Zhang, Weizhen; Zhang, Tao

doi:10.1111/ina.12748

Cited by 54 publications

(28 citation statements)

References 49 publications

(75 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…4 A recent study measured the sleep quality of young adults with polysomnography (PSG) at different CO 2 levels; the duration of deep sleep was found to decrease at higher CO 2 levels. 6 However, the CO 2 levels in this experiment were higher than have been observed in most field surveys. 5 To the best of our knowledge, no reports on the effects of bedroom ventilation on elderly subjects are available.…”

Section: Introductioncontrasting

confidence: 60%

“…The threshold of 1150 ppm was proposed based on Mishra et al’s study 4 . A recent study measured the sleep quality of young adults with polysomnography (PSG) at different CO 2 levels; the duration of deep sleep was found to decrease at higher CO 2 levels 6 . However, the CO 2 levels in this experiment were higher than have been observed in most field surveys 5 .…”

Section: Introductionmentioning

confidence: 70%

See 1 more Smart Citation

Pilot study of the effects of ventilation and ventilation noise on sleep quality in the young and elderly

et al. 2021

View full text Add to dashboard Cite

Three conditions were established to investigate the effects of ventilation and related ventilation noise on sleep quality: No mechanical ventilation/low noise (A); Mechanical ventilation /low noise (B); Mechanical ventilation/high noise (C). The interventions were achieved by idling a mechanical ventilation system or operating it in two different modes. Nine young people and nine older people were all exposed to each of the three conditions for a whole night's sleep, but data from only 15 subjects were analyzed as three young subjects apparently slept with open windows in condition A. Sleep quality was measured objectively with polysomnography (PSG), which monitored signals of electroencephalogram (EEG), bilateral electrooculogram (EOG), and chin electromyogram (EMG) continuously during the sleeping period. Saliva samples were collected before sleep at night and after waking in the morning, and the concentrations of cortisol and lysozyme in them were determined. Without mechanical ventilation, the indoor CO2 level averaged about 1400 ppm during the night. Operating the mechanical ventilation decreased the indoor CO2 to below 1000 ppm, which improved objectively measured sleep quality: wake time after sleep onset (WASO) decreased on average by 15 min (p < 0.05) and sleep efficiency (SE) increased on average by about 4% (p < 0.05). Increased ventilation noise level (50.8dB(A) vs. 34.7dB(A); 54.9dB(C) vs. 48dB(C)) did not significantly change SE or WASO but did change the duration of sleep stages: It decreased the duration of deep sleep by 11min (p < 0.05) and REM sleep by 17 min (p < 0.01) and increased the duration of light sleep by 17 min (p < 0.05). The ventilation noise significantly increased the concentration of lysozyme in the elderly (p < 0.05) although no significant effects on cortisol could be shown. These results confirm that a low ventilation rate has negative effects on sleep quality and that ventilation noise at or above 50dB(A) may disrupt sleep.

show abstract

Section: Introductioncontrasting

confidence: 60%

Section: Introductionmentioning

confidence: 70%

Pilot study of the effects of ventilation and ventilation noise on sleep quality in the young and elderly

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Where CER in L/h, VR in m 3 /h, C Steady : time‐average CO 2 concentration at the steady‐state period in ppm, C a : ambient CO 2 concentration in ppm under the period of steady state.…”

Section: Methodsmentioning

confidence: 99%

“…In the absence of other markers, its concentration indoors is frequently used as an indicator of the ventilation rate (VR) (when occupants are present) 2 and the degree of air mixing (ventilation efficiency) as well as indoor air quality (IAQ). Poor IAQ as indicated by a high CO 2 concentration has been shown to affect sleep quality and consequently next‐day work performance 3–5 . An increasing number of studies link bedroom ventilation to sleep quality 3–7 .…”

Section: Introductionmentioning

confidence: 99%

Emission rate of carbon dioxide while sleeping

et al. 2021

View full text Add to dashboard Cite

Humans emit carbon dioxide (CO2) as a product of their metabolism. Its concentration in buildings is used as a marker of ventilation rate (VR) and degree of mixing of supply air, and indoor air quality (IAQ). The CO2 emission rate (CER) may be used to estimate the ventilation rate. Many studies have measured CERs from subjects who were awake but little data are available from sleeping subjects and the present publication was intended to reduce this gap in knowledge. Seven females (29 ± 5 years old; BMI: 22.2 ± 0.8 kg/m2) and four males (27 ± 1 years old; BMI: 20.5 ± 1.5 kg/m2) slept for four consecutive nights in a specially constructed capsule at two temperatures (24 and 28°C) and two VRs that maintained CO2 levels at ca. 800 ppm and 1700 ppm simulating sleeping conditions reported in the literature. The order of exposure was balanced, and the first night was for adaptation. Their physiological responses, including heart rate, pNN50, core body temperature, and skin temperature, were measured as well as sleep quality, and subjective responses were collected each evening and morning. Measured steady‐state CO2 concentrations during sleep were used to estimate CERs with a mass‐balance equation. The average CER was 11.0 ± 1.4 L/h per person and was 8% higher for males than for females (P < 0.05). Increasing the temperature or decreasing IAQ by decreasing VR had no effects on measured CERs and caused no observable differences in physiological responses. We also calculated CERs for sleeping subjects using the published data on sleep energy expenditure (SEE) and Respiratory Quotient (RQ), and our measured CERs confirmed both these calculations and the CERs predicted using the equations provided by ASHRAE Standard 62.1, ASHRAE Handbook, and ASTM D6245‐18. The present results provide a valuable and helpful reference for the design and control of bedroom ventilation but require confirmation and extension to other age groups and populations.

show abstract

“…For example, Kajtar et al 12 reported that controlled human exposures to CO 2 between 2000 ppm and 5000 ppm, with ventilation rates unchanged, were positively associated with perception of wellbeing and performance on some reading tasks. More recently, a study by Xu et al 13 found that sleep quality was negatively affected by increasing concentrations of CO 2 up to 3000 ppm. Moreover, Mishra et al 14 showed that with lower CO 2 levels, the number of awakenings throughout the night tended to decrease.…”

Section: Introductionmentioning

confidence: 99%

Window operation behaviour and indoor air quality during lockdown: A monitoring-based simulation-assisted study in London

Tahmasebi

Wang

Cooper

et al. 2021

Building Services Engineering Research and Technology

View full text Add to dashboard Cite

The Covid-19 outbreak has resulted in new patterns of home occupancy, the implications of which for indoor air quality (IAQ) and energy use are not well-known. In this context, the present study investigates 8 flats in London to uncover if during a lockdown, (a) IAQ in the monitored flats deteriorated, (b) the patterns of window operation by occupants changed, and (c) more effective ventilation patterns could enhance IAQ without significant increases in heating energy demand. To this end, one-year’s worth of monitored data on indoor and outdoor environment along with occupant use of windows has been used to analyse the impact of lockdown on IAQ and infer probabilistic models of window operation behaviour. Moreover, using on-site CO2 data, monitored occupancy and operation of windows, the team has calibrated a thermal performance model of one of the flats to investigate the implications of alternative ventilation strategies. The results suggest that despite the extended occupancy during lockdown, occupants relied less on natural ventilation, which led to an increase of median CO2 concentration by up to 300 ppm. However, simple natural ventilation patterns or use of mechanical ventilation with heat recovery proves to be very effective to maintain acceptable IAQ. Practical application: This study provides evidence on the deterioration of indoor air quality resulting from homeworking during imposed lockdowns. It also tests and recommends specific ventilation strategies to maintain acceptable indoor air quality at home despite the extended occupancy hours.

show abstract

Experimental study on sleep quality affected by carbon dioxide concentration

Cited by 54 publications

References 49 publications

Pilot study of the effects of ventilation and ventilation noise on sleep quality in the young and elderly

Pilot study of the effects of ventilation and ventilation noise on sleep quality in the young and elderly

Emission rate of carbon dioxide while sleeping

Window operation behaviour and indoor air quality during lockdown: A monitoring-based simulation-assisted study in London

Contact Info

Product

Resources

About