To sleep, perchance to dream – but only with the window open

Recent research has shown that adequate ventilation in the bedroom is vital for our wellbeing – as well as our performance at work the next day

We spend around one-third of our lives asleep. In contrast, we only spend around one-tenth of our lives at work.

A new study carried out by the department of civil engineering, DTU Byg, has demonstrated that the indoor climate in the bedroom where we sleep has a significant effect on our performance on the following day.

READ ALSO: Danish researcher part of team that finds brain’s sleep switch

“A lot of us shut both our bedroom doors and windows in order to get peace and quiet. But if you don’t have adequate ventilation in the room, the quality of the air can become really bad during the night,” explained Pawel Wargocki, an academic at the department responsible for carrying out the research.

Men performing badly
Sixteen residents of a college dormitory had a mechanical ventilation system installed in their rooms that was activated when the air quality became bad; one week the ventilator was turned on, the next week it was turned off. The inmates were not informed whether it was on or off.

Every morning they were asked to fill in a questionnaire about their sleeping patterns and perform a number of feats of logic, in which they were required to understand sentences and answer questions on them.

The ‘guinea pigs’ were also equipped with electronic meters that could record when they slept. “We could clearly measure that they performed much worse on the days when they neither had mechanical or natural ventilation in the form of an open window. At the same time, they all reported they had slept badly,” Wargocki said.

There’s something in the air
The experiment showed that the level of CO2 increased significantly in a tightly-closed bedroom. This is not necessarily the only thing that makes bad air; researchers are still studying how CO2 concentrations influence learning and powers of concentration.

However, “a high CO2 concentration is an indicator that the air is also polluted with other elements that have a negative effect,” continued Wargocki.

This could be anything from pollution emanating from the materials used in the construction of the building to dust particles from furniture and gasses released by electronic apparatus such as fridges, TVs and computers.

That’s why it is not always enough to merely open the bedroom door a fraction to the rest of the house. It might thin out the bad air in the bedroom, but this can only be completely removed by proper ventilation.

Some like it hot – but not too hot
Wargocki thinks we ought to be much more aware about the quality of the air in our homes, and especially in the bedroom, where we spend a considerable amount of time. Whether we sleep best at 12 degrees or prefer warmer temperatures is an individual thing, but proper ventilation is all-important.

However, Wargocki points out it is important to avoid too high a temperature in the bedroom: “If the temperature gets above 26-27 degrees or thereabouts, it is impossible to get rid of the heat – even if you sleep naked.”




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