The renovation is completed, or a brand-new building is ready, and people can move in. Everything should be in order: the premises are comfortable and everything smells new. But after a while, the people start experiencing various symptoms: headaches, skin symptoms, maybe maxillary sinusitis and fever. Why? After all, they’ve just moved into comfortable new premises. This question is frequently asked.
What causes symptoms in new buildings?
The most common cause is volatile organic compounds (VOC). There is a strong smell of materials in new buildings, just like when you walk into a furniture shop. The odours or VOCs come from construction materials and adhesives and fillers used in boards (e.g. furniture boards, acoustic boards, etc.). In addition, textiles found in a building are treated with fire retardants that release VOCs. Detergents and waxes add their own odours to indoor air. Odours are stronger in rooms where the ventilation is insufficient, or where the room temperature is high.
Emissions from materials can be higher in new buildings for the first six months or even longer. That is why more efficient ventilation is recommended during the first months. Efficient ventilation helps to flush the compounds released from materials out more quickly.
Construction dust remains suspended in indoor air
Dust emissions during the construction phase can remain in new buildings despite careful cleaning before the use of the premises. Dust remains in the air for a long time and settles slowly. Dust consists of particles that can be divided into four size categories:
- Large particles
- Coarse particles
- Fine particles
- Ultrafine particles
It can take even weeks for them to settle.
Table: Characteristics of dust particles of various sizes
Particle |
Size |
Suspension time |
Phase in the body |
Origin |
|
Large particles |
Typically ∅ 50 μm – 125 µm |
Varies depending on the size |
Remain in the nose and on the mucous membranes of the eyes, can enter the digestive system from the hands |
Anthropogenic and natural particles, particle clusters and fibres. Road dust, sand dust, mineral dust, pollen, mould spores, allergens |
|
Dust |
below 100 µm |
From seconds to hours |
Remain in the nose and the upper respiratory tract |
Cloth dust, fibres from construction materials |
|
Inhalable particles = coarse particles |
2.5–10 µm |
|||
|
Fine particles |
below 2.5 µm |
From days to weeks |
Travel to small unciliated bronchi and alveoli |
Combustion products from vehicles, camp fires, smoking, soot, oil and heavy metal particles |
|
Ultrafine particles |
below 0.1 µm |
- |
Travel to alveoli and parts of the circulation |
Table 1: Characteristics of dust particles of various sizes (1)
Careful cleaning before the use of the premises removes most of the particles in the air. However, careful protection even during the construction/renovation phase is most important. This helps avoid the collection of impurities in, for example, ventilation channels, pipes and the tops of lamps and their attachments to wall surfaces.
Careful cleaning is not always enough, however, because the dust suspended in the air continues to settle for several days after cleaning. Construction materials and adhesive boards in new furniture release VOCs long after they have started being used. In new buildings, intensive indoor air purification is often required for the first six months.
Other routes of impurities
Old furniture, other personal belongings and textiles are often brought to new buildings, and sometimes they have been used in a building that has problems with indoor air quality. In this case, the furniture and materials can carry impurities that can cause symptoms to the people using the new building. Damaged materials should be disposed of before moving the furniture and personal belongings. A rule of thumb is to clean all hard materials carefully. Soft materials (e.g. pillows, rugs, etc.) should be washed in as high a temperature as possible, following the washing instructions. Ozonation can be used to clean large furniture or personal property that is hard to clean.
SOURCES:
1) Pesonen-Leinonen, Eija: Sisäilman käsiteet ja siivouksen rooli.
.png)