Buildings are becoming more and more energy efficient and therefore more closed to the environment. This is where the air quality in the interior is playing an increasingly important role. By using appropriate filters (active carbon filters, fine dust filters, ionisation devices, humidifiers with filters, etc.), the air quality can be improved. ), the air quality can be actively influenced. The quality is significantly influenced by the amount of fine dust, spores, toxins, germs and other micro-particles present. According to a study by the Harvard T.H. Chan School of Public Health's Centre for Health and the Global Environment, SUNY Upstate Medical University, and Syracuse University Environmental influences such as indoor air pollution and its CO2 content have a much higher impact on our mental performance than previously thought. Studied offices with greenery compared to offices without greenery.
"green" vs. "non-green". The presumption was that plants improve air quality and thus increase cognitive performance as well as functional work performance - i.e. overall productivity.. Nine parameters were measured to assess cognitive performance. For 6 days, participants in this experiment worked in environments where they were exposed to different environmental conditions. Participants in a "green+" (meaning plants + ventilation)-group performed twice as well as participants in a normal environment. People in a "green" environment performed 66% better.  The greatest improvements were seen in the areas of:

• crisis management (97% higher in "green" and 131% higher in "green+")

• Strategy (183% higher "green" and 288% "green+")

• Information use (172% "green" and 299% green+)

In addition, the researchers are looking at the effects of. CO₂ on the subjects,  which is not normally considered indoor pollution. They found that7 out of 9 cognitive ability parameters deteriorated as CO₂  concentration increased to levels have been raised to levels often found in offices.

An optimal indoor environment consists of several factors
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• Air temperature.

• Toxic diseases
  

• Humidity

• Air movement/air speed.

• Air quality

 
In order to optimally design the working environment and thus increase the attention, concentration and ultimately the health of the employees, the temperature must be taken into account in addition to the air humidity and the air volume. A system that works hygienically minimises negative aspects. Roughly speaking, the temperature should be between 20 and 22C°. A temperature difference of more than 4 degrees between head and foot should be avoided. The air speed should not exceed 0.15 m/s and the humidity should be between 40 and 60%.

 

Employee satisfaction and productivity

Increased employee satisfaction has become more and more the focus of company management, not only due to bona fide employers and a shortage of skilled workers. It has been proven that a good working atmosphere and working environment increases productivity, identification with the company and also means lower fluctuation. According to a Meta.study from . Havard Buisness Review magazine, which analysed and evaluated hundreds of studies on the topic of employee satisfaction, satisfied employees are 31% more productive and 37% more successful with three times higher creativity. One pillar of good employee satisfaction is the location of the workplace. In this respect, air is indispensable. The fact that air is a medium we constantly consume makes it, along with water, the cornerstone of our lives. Nitrogenous air and a high CO2 concentration have far greater consequences than previously assumed.

air temperature.

The room temperature should be generally conducive to health and not detrimental. Depending on the type of activity, there are different guideline values for the right temperature. For an office workplace, the values should be min. 18°C and max. 26°C. Excessive temperature fluctuations should be avoided. Accordingly, the workplace should be able to be darkened against heat radiation (e.g. the sun). Room temperatures above 26°C  should be avoided. An optimal room temperature is difficult to determine, however, as individual personal sensation varies greatly .

Science proves link between temperature and productivity

In a study. of Cornell's Human Factors and Ergonomics Laboratory in Orlando (Florida) on the relationship between indoor climate and productivity, it could be proven that there is a direct correlation between indoor climatic conditions inside closed rooms and the errors made by employees during keystrokes. In addition, a direct correlation between air conditions and employee activity was found. The temperature and humidity at the subjects' workstations were recorded every 15 minutes. During the course of the study, it was found that at 25°C productivity was 100% the error rate was 10%. When the room temperature was cooled to 20°C, productivity dropped to 54% and the error rate increased to 25%.

Air movement

The air speed can be described like a breeze blowing through the room. This can be influenced by an air conditioner, a fan or by opening windows. If the air exchange is too weak, the CO2 content increases and we have the feeling that the air is used up. If the draught is too strong, we often feel it to be cool or uncomfortable.

C O₂ Salary       

The generally targeted maximum value for . CO₂ for indoor environments is about 1000ppm. For comparison, the content of CO₂ in outdoor air is currently around 400ppm. From a value above 2000ppm, measures should definitely be taken to enable the exchange of indoor air, as hygienic and cognitive disadvantages already come into play here.

[Sayers et al. 1987] conducted short-term chamber studies on the influence of high CO2 concentrations (above the occupational exposure limit of 5000 ppm) on mental performance. Twenty-one young adult subjects breathed CO2 concentrations of 0, 45,000, 55,000, 65,000 or 75,000 ppm at a constant oxygen (O2) concentration of 21 vol-% for 20 minutes in each of 5 experimental cycles. Comprehension and short-term memory tests were performed before, during and after exposure. While logical reasoning and short-term memory were not significantly affected by the high CO2 concentrations, thinking performance was significantly slowed.

Sayers JA, Smith REA, Holland RL, Keatinge WR (1987) Effects of carbon dioxide on mental performance. J Appl Physiol 63:25-30 .

CO₂ as Hygienic Conductance 

"The US Environmental Protection Agency  conducted  a  study in 100 randomly-selected -office buildings with no specific cause for complaint between  1994  and  1998 . Among other things, the study analysed the relationship between mucous membrane irritation, upper respiratory tract complaints and the carbon dioxide concentration in the indoor air, reduced by the CO2 concentration of the outdoor air. For mucosal and respiratory symptoms, a significant  increase  per  increase  in  CO2 concentration difference was found by 100 ppm. A  significant  and  marked  dose-response relationship  of the  increase  in  CO2 difference was demonstrated for the symptom groups sore throat and whistling breath sound."        

Notice of the Federal Environment Agency "Health assessment of carbon dioxide in indoor air"             

The American scientists Rudnick and Milton studied in 2003,  the flu contagion risk in a classroom of 30 people, the test groups were in the classroom for four hours, one person had acute flu. The results were: At 1,000 ppm CO₂ five people became infected, at 2,000 ppm it was already twelve and at 3,000 ppm even 15.

Relative humidity

Ausgangstext Ausgangssprache auswählenÜbersetze Deutsch (erkannt) " „Trockene Luft“ und ihre Auswirkungen auf die Gesundheit – Ergebnisse einer Literaturstudie " " Übersetzter Text Zielsprache auswählenÜbersetze nach Englisch (UK) " "Dry air" and its effects on health - results of a literature study " The employer shall determine which occupational safety and health measures are necessary by assessing the hazards associated with the employees' work. Einfügen in ... Kopieren Klicken Sie auf ein Wort, um es nachzuschlagen oder um alternative Übersetzungen zu sehen.

"As part of a literature study,which was carried out by the Berufsgenossenschaftliches Institut für Arbeitsschutz - BGIA at the behest of the Verwaltungs-Berufsgenossenschaft,these questions were to be clarified so that soundrecommendations on the level of relative humidity and resulting measures  can be derived in future. "

"Most studies conclude that an increase in relative humidity can reduce the likelihood of contracting an influenza infection. Several direct and indirect effects of relative humidity are thought to be responsible for this."

In this literature study, it was found that pathogens were worse able to disperse and survive in relative humidity above 40%, benefiting from dust formation and increased airborne particles at lower humidity.

"However, it is undisputed that pathogens in indoor air have a lifespan that is dependent on the relative humidity of the air . In addition, with increasing relative humidity, not only the particle size of microorganisms but also of dust particles grows due to water accumulation, causing them to sink faster, which leads to a purification of the air. Nuisances caused by electrostatic effects can be minimised by increasing the relative  humidity to 40 to 45%. The problem of dry eyes or skin may also be improved by increasing the relative humidity in this area. "

Dry air and its effects  on health - results of a literature study N. von Hahn

In almost every modern building you can find ventilation systems or ceiling air conditioners. Whether in public buildings, office buildings or industrial complexes. The requirements of air handling units are as varied as their possible applications. They enable the climatic conditions in buildings to be kept constant and adjustments to be made in a controlled manner. In order for these systems to function as desired, the operator must fulfil continuous control and maintenance requirements and document them, comparable to the requirements of the TÜV for a car. Regular cleaning and hygiene checks are therefore very important in the eyes of the legislator. The hygienically impeccable condition of an air handling unit is crucial for its positive use.

Started at Bacterial infestation in humidifier systems or in the scrubber chambers above humid air ducts and filter stages: Improper care and carelessness can trigger problems in an AHU that can quickly turn the intended improvement in indoor air into its opposite. Allergic reactions to certain fungal spores or pollen, airborne infectious diseases, toxic alevolitis and numerous other illnesses can be the result of a dirty, improperly maintained AHU. Krölling (1989) found in a study that almost 20 % of about 2.5 million citizens of the old federal states who worked in buildings with air conditioning systems reported complaints. According to this study, people who work in air-conditioned buildings are twice as likely to suffer from colds and health complaints as people who are not "exposed" to air conditioning systems.

"

"The spread of pathogens through air conditioning systems, as well as the possible  disturbances of well-being, have been known for a long time (Elixmann 1988, Kröling 1989, Seifert 1991).   Germs from the outside air, as well as microorganisms naturally occurring in water  can  enter  the humidifier systems  of air handling units. If they find favourable conditions, they are able to survive and multiply (Jäggi and Schmidt-Lorenz 1990, Schata 1995, Boe-Hansen 2001). This spectrum includes viruses, bacteria, fungi, spores and algae. The airborne biological particles are called bioaerosols. This includes not only the above-mentioned microorganisms themselves, but also their metabolic products. These include also cell products (enzymes), cell decay products (glucans and endotoxins), microbial volatile organic compounds (mVOC) and mycotoxins (fungal toxins). Through the ventilation shafts and filter stages, contamination of the workrooms with pathogenic germs and their decay products can then occur. "*

*Dissertation by Sabine Harder. to obtain a doctorate in medicine.
"Studies on the contamination kinetics of launderers. amber water room air. installations after different cleaning procedures. en" "

Infectious diseases caused by Legionella spez

The most common diseases caused by Legionella are acute bacterial infections of the respiratory tract.
The Legionellacea family includes 48 genera and 70 serogroups. The most important species affecting humans is Legionella pneumophilia with about 16 known serogroups, to which about 90% of all infections are attributed. They have been detected in temperature ranges of 0-63°C and feel most comfortable in the range of 25-42°C.They are often integrated into amoebae and biofilms and are thus chlorine-tolerant and thus survive water treatment processes (Exner and Schulze Röbbeke 1987, Exner et al. 1987).They colonise in all water-bearing systems, especially if these are poorly maintained and stand still. Even at low concentrations, infections can occur - this was demonstrated by Heudorf et al.(2001).

Infection occurs through swallowing water or inhaling aerosol contaminated with Legionella. Since 2001, there has been an obligation to report legionellosis under the Infection Protection Act.The most common clinical syndromes are legionellosis "Legionnaires' disease" and Pontiac fever.

Legionellosis " Legionnaires' disease"

Die Legionellose ist eine atypische, schwer verlaufende Lungenentzündung. Sie wird meist durch das Einatmen von kontaminierten Aerosolen oder dem Verschlucken von kontaminierten Wasser verursacht. Die Legionärskrankheit erhielt ihren Namen, da sie nach einem Treffen der US-Kriegsveteranenvereinigung  American Legiond, dass 1976 in einem Hotel in Philladelphia stattfand, erstmals in großem Maßstab auftrat. Damals erkrankten 181 vorzugsweise ältere Personen an lebensbedrohlichen Lungenentzündungen. Symptome reichen von Kopfschmerzen über Fiber bis hin zu blutigem Stuhl.

Pontiac fever

Similar to influenza in its course and named after an epidemic in 1968 in Pontiac/USA. With an incubation period of 1-2 days and a very high morbidity rate, it manifests itself in 90% of those exposed to legionella. It often begins with headaches, aching limbs, discomfort, fever, cough and dizziness. The illness usually resolves completely after a week and does not require further therapy.

Diseases related to the workplace.

Sick Building Syndrome

In the mid-70s, there was an increase in non-specific illnesses that were registered in people who are employed indoors in commercial, public or private buildings. Common symptoms are general malaise or fatigue. Other symptoms include fatigue, headache, drowsiness, difficulty concentrating, burning eyes, eye irritation, nasal discomfort, dry throat, sore throat and rheumatic complaints. Finnegan et al. (1984) conducted a wide-ranging study which found that workers in office buildings with air conditioning systems had far more complaints of mucous membrane irritation and headaches than workers in rooms without air conditioning.

Building Related Illness

Here the symptoms are specific and, in contrast to sick building syndrome, clearly defined. The symptoms can be directly attributed to being in a building and do not subside for several days after leaving the building. Clinical syndromes are legionellosis, mould and house dust mite allergy, asthma and humidifier fever (Seifert 1991, Welch 1991, Wiesmüller and Bischof 2006). The causes of the diseases can be traced directly to the buildings during a clinical examination.

Allergic diseases.

"According to Coombs and Gell, allergies are divided into 4 types. Im  Related to ventilation systems and humidification. systems. may be type I, type III and type IV allergies.Typical allergens are. moulds and their spores, animal proteins, and chemical substances that are inhaled in the form of dusts" (Kampen v. et al. 2000).

Type I Allgerie1 .

5-20 % of the population in Western industrialised countries suffer from manifest type I allergies. Moulds belong to the important indoor allergens, the genera Aspergillus  being the most important. and Penicillium indoors and Alternaria and Cladosporum in d. er. outdoor air the main representatives.

The Type III / Type IV allergy.

You can use the same occur side by side, clinical correlate is the exogenous. -allergic  Alveolitis . It is through the i. nhalative uptake of antigens. to obtain an immunological mainly interstitial pneumonia (Ring 2004).
*Dissertation by Sabine Harder. to obtain the degree of Doctor of Medicine.
Studies on the contamination kinetics of. laundry amber water room installations according to different cleaning procedures
.

Exogenous allergic alveolitis.

Diseases associated with humidifiers and cold nebulisers also occur in the general population. Patients have fever, cough, sputum and dyspnoea. As it occurs in various clinical clinical pictures, exogenous allergic alveolitis has been included in the catalogue of occupational diseases in Europe as EAA. It occurs more frequently in occupations where organic dust containing moulds or animal protein components is inhaled. It causes an allergic inflammation of the lung tissue. It is also called farmer's lung, birdman's lung or humidifier's lung. An acute and a chronic course can be distinguished.

Toxic diseases
.

Toxic alveolitis

To be distinguished from EEA is toxic alveolite. A condition caused by metabolic products such as mycotoxins, enzymes, organic components of bacteria, endotoxins produced by bacteria and components of fungi. Toxic alveolitis occurs rapidly after exposure and usually resolves within 24-48. Symptoms are similar to EEA.

Organic dust Toxic Syndrome

The so-called ODTS is caused by the toxic components of so-called endotoxins and glucans. In this case, no sensitisation phase is required. The first symptoms appear almost immediately after exposure (1 to 2 hours).
The symptoms are similar to toxic alveolitis. In some cases, a slight fever with cough occurs after about 4 to 12 hours.