Mould growth

Bio-based insulation materials represent an alternative to petro-based materials which may contribute to enhance buildings energy efficiency. Nevertheless, these material must respond to indoor air quality requirements and prove their resistance to moulds. In this study, VOCs emissions of a wood fibre board were characterised at 50% and 85% of relative humidity (RH) as well as its potential to mould growth. Relative humidity variation impacted significantly some VOCs emissions and colonies from Aspergillus niger developed onto the material.

Scientific evidence exists of an association between dampness and mould in buildings and of an increased risk of health effects for occupants, usually associated with the respiratory system. It is difficult to establish the exact prevalence of residential dampness, but according to WHO, it is likely to be in the order of 10-50%.  

It is not unusual to face moisture problems in buildings in cold climates and wet regions. It is, however, unusual to have the same problem in a relatively dry region such as Jordon, which has moderate weather conditions and mild winters. Nevertheless, a significant proportion of houses and residential apartments in Jordan are affected. The monitoring of inside air conditions, wall surface temperatures, ventilation and living style has shown that a high relative humidity (RH >75%) occurs at walls resulting in possible condensation.

Malaysia is situated near the equator of earth where the weather is hot and humid. The vulnerableenvironment has induced many Indoor Air Quality (IAQ) concerns in hospitals by health professions inmany countries. There is mounting evidence on IAQ exposure leading to excessive morbidity andmortality. Many extensive studies have been conducted but there is not many IAQ standard to-date.The objective of the study is to present the finding of the source of indoor air quality in a new hospital inMalaysia. The study also presents the solution to overcome the IAQ problem faced by the hospital.

In buildings growing conditions for mould fungi can occur and cause fungus infestation. Therefore,consequent measures have to be taken to avoid health dangers that come from mould fungi inbuildings. In order to avoid the mould fungus formation, a strategy has to be set up that focuses on thegrowth conditions for mould fungi. While in Germany only relative humidity is used as an assessmentcriterion for mould growth risk, more and more measured isopleths are used abroad.