An argument for a reality check in the ventilation industry: We still have an energy crisis, in practice, and are not generally, in practice, achieving better indoor climate

In 2017 the Danish Building and Property Agency started a project titled “Avoiding energy waste in ventilation systems” by tracking the actual energy use in a sample of their 4 million m2 portfolio of buildings through on-line energy management tools. The project is not complete, but the key preliminary findings  described in this paper are: 

Feedback on installation, maintenance, and aging of mechanical humidity-controlled ventilation exhaust units

With 35 years of existence and more than 10 million equipped dwellings, mechanical humidity-based demand-controlled ventilation (RH-DCV) can provide a comprehensive feedback on installation, aging, and maintenance of its components. Their working principle is based on the extensions and retractions of a hygroscopic fabric, which pulls on a shutter to modify the device’s cross-section – hence the airflow – upon humidity changes in their environment. 


This report describes the results from the questionnaire and detailed survey conducted in 2004 to 2006.The 15 items of questionnaire included in facilities management, maintenance management, savingenergy, art gallery facilities. The number of art galleries investigated by questionnaire survey is about171 art galleries in Japan. Then we scanned findings during about 1 year 6 months to get speculationhaving high reliability and summarized a tendency and a characteristic based on the result. Fromthesurvey results, it shows the tendency and characteristics about each item.

Study on Performance Evaluation of Mechanical Ventilation Systems for Occupied Houses

In the first phase of the current project, the ventilation rates of occupied houses in the northern region of Japan were investigated from 2001 to 2005. It was revealed that, despite installing mechanical ventilation system, low ventilation rate was found in many houses. The causes were believed attributing to lack of cleaning of grills, filters and insect protection meshes. The second phase of the project was to investigate the causes and resolve the problems. This project was started in 2005 and 12 houses installed with mechanical ventilation system were investigated.

Surface dust contamination and perceived indoor environment in office buildings

The aim of that study was to test the impact of cleaning on indoor environement quality. Surface dust measurements were made on samples taken from office rooms before and after cleaning during the heating period of the buildings. Before the sampling, the occupants completed a questionnaire survey. The data were analyzed then discussed.

HVAC - The importance of clean intake section and dry air filter in cold climate

In this paper, practical recommendations for design and operation of HVAC systems are presented. The result of a proper maintenance will be less pollution and a better indoor environmental quality.

Moyens et méthodes pour l'hygiénisation des réseaux Means and methods for the cleaning of air-handling ducts

The search for top quality is the requirement of the professionals of "hygienisation". A description of desinfection with its methodology applied to ducts is presented : dust removal, cleaning of the surfaces before their disinfection.

Some schools at risk for poor IAQ

In this paper, the author presents what could be done to improve the poor indoor air quality in some schools :- A demand for accountability from school systems about maintenance procedures such as roof-leak repair, classroom ventilation and air-conditioning, presence and care of carpeting etc.- A promotion of a responsible and adequate funding for the maintenance of public facilities- The most important activity is a good, basic, responsive and adequately funded building maintenance.

A gravimetric measurement method for ventilation cleanliness, before and after cleaning. Description and application.

The cleaning of HVAC systems aims at removing contaminants and re-establishing the function of the system of ventilation.A measurement method for ventilation cleanliness is discussed in this paper. It is based on measuring the dust deposits inside ducts. Comparison of that HVAC cleanliness method is made with others.

La désinfection des réseaux aérauliques Disinfection of air-handling ducts

A kind of protocol for the desinfection of air-handling ducts is presented in this paper with its different steps : relationship with the customer, available techniques, prerequisites for the desinfection, choice of the products and the desinfection itself.
The limits of the system are presented too along with possibilities to develop.