Ventilation technology has a long history and has gradually developed alongside the changes brought about by the evolution of industries and buildings as well as changes in our personal needs.
The word ‘ventilation’ comes from the Latin ventilatio, in turn from ventus meaning wind, which was described in 1660 as a process to ‘replace poor air in an enclosed space with new and clean air’. It was also used early on to mean ‘breathing’, i.e. the exchange of oxygen and carbon dioxide in our lungs. The term was thus used to describe a process that was that was liberating, cleansing and necessary.
The Swedish word vind, meaning both wind and loft, is also derived from ventus. In Old Swedish, the vind was the highest part of a building, the place under the roof where it was draughty. The word ‘loft’ in Swedish is also related to the Swedish words for air – luft and for smell – lukt. There is obviously a very early connection between the idea of ventilation and air quality, and it is, therefore, not so surprising that ventilation and health were linked together from a very early date. However, from a technical perspective, ventilation and heating were, for a long time, the results of one and the same idea. Consequently, there was no specific point in time when the very first system was invented or put into use purely for ventilation purposes.
During the Middle Ages, air was still regarded as one of the four elements, which, together with fire, earth and water, made up the world. The purpose of breathing was to cool the heart, which was filled with the element fire. Furthermore, at this time, it was commonly known that poor, standing air contained mysterious gases that caused diseases and even death. This was readily observed, as mines were being excavated to increasingly deeper depths. The economic incentives to continue mining eventually led to a number of technically advanced ventilation solutions in the middle of the 1500s. These involved not only the use of fire as a driving force but also manually-driven wooden fans and bellows. Later on, these ideas were adapted for use in buildings and remained in use for a long time to come.
When towns began to grow in the 1700s, and housing conditions became more cramped and sanitary solutions inadequate, health issues became increasingly more acute. It was suspected that certain diseases were airborne and ventilation to create sound indoor air was given high priority, especially in buildings where it was particularly obvious that diseases and ill-health were easily spread. Included in this category were prisons, ships, military barracks and, ironically, hospitals. Around 1770, there was scientific proof that fresh air was, in fact, healthier than stale indoor air. Poor air was also known to contain high concentrations of carbon dioxide, moisture and pollutants emanating from various sources such as humans, torches and fuel lamps.