Dust from building activity such as concrete, gypsum, wood and other building materials will cover all horizontal surfaces, and if in addition the air humidity is high, it will adhere to all surfaces.
Ventilation systems can make the contamination worse. The risk caused by this type of damage is primarily reduced by cooling of electronic and electric parts. In case of heavy dust contamination heating may result in fire.
In the case of fine-grained dust, the fire can be explosive.
Some types of dust are capable of conducting electricity. In current-carrying apparatus and plant this type of dust can cause short-circuit and electrical arcing. When analysing dust from production plants in the food industry it often contains salt which is corrosive.
Powder damage from AB and ABC fire extinguishers frequently cause secondary damage when used to extinguish the fire or because they are used in acts of vandalism. The powder is a hygroscopic product, which attracts humidity to the surface and can result in the corrosion of metal surfaces.
Excessive wear of plant/equipment
Secondary damage caused by dust and powder damage is an often neglected cause of damage on movable parts such as ball bearings and axles. Fine-grained dust can act as a polishing powder and shorten the lifetime on moving parts in the equipment.
Our choice of first aid is decided on a case by case basis. It is important that contamination is reduced so that it does not spread into other parts of the building by means of air circulation or when blowing the dust away. At the same time dry cleaning of electronics must be handled with care due to electro-static sensitive devices. Generally an air humidity of 35% is recommended.
Tests have shown that, for particle size of <50µm, purely dry process will often only remove 10% of the contamination. Therefore a wet process must be used in these cases.