Indoor Air Quality: Towards a Revision of the Regulations on Ventilation

Specialists in the quality of indoor air held a meeting under the initiative of the Energy Balance Association with respect to a revision of ventilation regulations. This meeting focused on the lack of regulations concerning the ventilation, and the confusion around regulations relating to the tertiary sector and residential homes.

The Energy Balance Association organised a discussion workshop on the decisions concerning the preservation of indoor air quality. On the same day, Ségolène Royal announced the postponement of the January 2015 date for the obligation to measure the air quality in nurseries coming into force.

According to Ms. Andrée Buchmann, President of the Observatory for the quality of indoor air (OQIA) obligations and systematic controls for boilers with CO₂ emissions is a good way to deal with the important issues in our society. A change in behaviour is essential to oblige professionals and authorities to invest in this way.

Dr. Suzanne Déoux, president of the Association of Building Health and Mr. Pierre-Louis François president of Uniclima (union of the thermal, air and refrigerated industries) have joined this cause. The establishment of uniform systematic checks could however be counter-productive and useless if it does not take into account geographical and environmental contexts.

The technical recommendations should therefore vary according to the different situations of the fact that there is no single solution. According to Mr. Pierre-Louis François “We shall not equip with the same system of ventilation a building situated at the edge of the Parisian beltway and another one in the countryside”.

Conflicting regulations on the regulations on the ventilation

The three experts noticed many contradictions in the regulations. The ventilation of commercial buildings is governed by the Labour Code for local so-called “non-specific pollution” while they have to conform to the thermal regulations. Education locals are governed by departmental sanitary regulations of hygiene (DSRH). The Labour code imposes the renewal of air of 25m³/h for a teacher whereas the DSRH requires18 m³/h for a high school student.

Mr. Pierre-Louis François wishes to point out that France and Scandinavia were at the forefront. The introduction of the concept of general and permanent ventilation associated with the obligation of air inlets in dry rooms and extractors in wet rooms began in 1969. There had also been the generalisation of the concept of controlled ventilation and minimum flow between 1982 and 1983. The orders of March 24th, 1982 and October 28th, 1983 are always applicable 32 and 31 years after their promulgation. France is less well advanced in terms of humidity sensitive ventilation system compared to the Germanic countries that have adopted technological equipment and a generalization of the VMC turbofan.

Prioritising energy criterion

4 thermal regulations (TR) referred on the texts of 1982 and 1983 to innovate VMC installations – a device which has focused on the energy criterion in the field of ventilation regardless of health criteria.

Construction projects between 1982 and 1990 are mostly equipped with self-adjusting VMC. VMC humidity control with an average flow divided by 2 was adopted between 2000 and 2005. The TR2012 application once again halved the permeability of the frame with 0.6 m³ / h. m², reducing by 20% air exchange rates.

According to Uniclima, the individual house of 110 m² T4 with an air flow of 145 m³ / h with 0.53 vol/h is now increased to 62 m³ / h with 0.22 vol/h. The air change rate in the collective housing also fell today with only 0.36 vol / h for a T4 of 84 m².

This situation is largely due to the growth of the concern on the outdoor air quality and the urban densification.

According to Uniclima, TR2012 is the cause of the disappearance of the turbofan developed between 2005 and 2012 in individual houses with the labels BBC TR2005. The main cause is indeed abandoning the encouragement of devices with filtration.

Better ventilation in commercial buildings than residential

The definition of minimum air flows in commercial buildings has improved ventilation in these buildings. In 2004, regulations focused on sensing devices or CO2 sensors, disregarding “hygro” systems.

The minimum air flow levels were maintained for thirty years in the tertiary sector. To meet the requirements of energy consumption mentioned in the TR 2012, the sector turned to dual stream offering both filtration and heat recovery systems.

This has resulted in a significant difference between ventilation in homes and the tertiary sector like office, hotels, restaurants and schools. The French people on the other hand spend two-thirds of their time in homes and less time in offices.

The experts stressed “It would be reasonable to change the regulation of housing with larger air exchange rates to meet the health challenges”. For his part, Pierre-Louis François said “We recommend a progressive and experimental approach by taking advantage in particular of future environmental labels”. In addition, he suggests for collective housing and houses built in urban zones, the installation of innovative CO₂ presence detector or control systems of the VMC allowing limiting the energy consumption.

Andrée Buchmann argues that it is not required to comply with inappropriate standards to different situations. She also argues that the TR 2012 must take into account certain criteria such as location and not require vents or ventilation systems. A targeted approach and a lot of thoughts will be, according to her, necessary to find the best way to renew the air of a building.

Follow up the implementation

Control of the site would be – for Dr. Suzanne Déoux – an important step in improving the quality of indoor air (QIA). Improper installation of ventilation systems is a degradation factor of the QIA in buildings. The waterproofness control of buildings, checking of the functioning of the installations and air renewal must be compulsory according to her. Uniclima president has meanwhile stressed the urgency of implementing a control at the reception of the site by a survey conducted in several building lots. He also proposed the addition of a specific lot “ventilation” in the tender (CCTP) for collective housing in which the VMC installations are mainly failing.