We all know that there is particulate matter in the air – we can see it floating in sunlight or over the beam of a projector. What you might not know is that there are many other particles present in indoor and outdoor air that are much too small to see. These particles, less than 0.1 micron in diameter, are known as "Ultrafine Particles or "Nanoparticles."
The main source of such particles in our daily life is the combustion engine, in particular diesel engines. Petroleum fuel burns – but not completely. One of the bi-products of incomplete combustion is ultrafine particulate, or UFP. Thus, outdoor levels of UFP tend to be highest in urban areas with high traffic concentrations.
And yet some people may be getting more of a dose of UFP than they imagine. Studies have shown that some office equipment, such as printers and faxes, can give off substantial numbers of UFPs. These UFPS impact indoor air quality.
Some immediate signs that high levels of UFPs are present in a building include eye, nose, and throat irritation. Some more serious health effects of prolonged exposure to UFPs include asthma exacerbation and respiratory problems.
The reason these particles can cause discomfort and health problems is their size. Once these particles are inhaled, they can penetrate deep into lung tissue, and even have the capability of moving to other organs. Studies have shown that these particles may travel from the nose and throat region to a portion of the brain via neural cells. Research has also shown that, because of these particles' extremely small size, they are able to penetrate into the mitochondria of individual cells.
The reason why UFPs can cause health problems has do to with their size as it relates to total surface area. This large surface area attracts chemicals, which are then adsorbed onto the surface of the particle. When the particle is inhaled, the chemicals may be released, causing cellular damage, inflammation, and oxidative stress.
Ultrafine particles from office equipment should not cause problems as long as the ventilation system design is sound and is running properly. Many indoor spaces are not provided with sufficient makeup (outdoor) air. When this happens, contaminants such as UFPs can build up and cause irritation, discomfort, and even health problems.
Should you be interested to know whether your HVAC system is operating effectively, or would like measurement of indoor contaminants such as UFPs, you should retain the services of a reputable industrial hygiene consulting firm. These consultants can assess the HVAC system's operation, and can measure airborne concentrations of many different contaminants.
For more information download our paper outlining common indoor air quality test parameters.