Language:   Useful Links: FAQs Sitemap  
Home  /  Articles  



April 28, 2011


Ventilation is the intentional movement of air from outside a building to the inside. Ventilation air, as defined in ASHRAE Standard 62.1 is that air used for providing acceptable indoor air quality.

IAQ refers to the nature of conditioned air that circulates throughout the space/area where we work and live, that is, the air we breathe during most of our lives.  IAQ, refers not only to comfort, which is affected by temperature, humidity and odours, but, also to harmful biological contaminants and chemicals present in the conditioned space.

We try and maintain a healthy the environment in our homes by keeping the windows open  if  the room feels stuffy, using exhaust fans in the kitchen and toilets to clear smoke and odours, etc. However, it is not so easy do so in modern commercial structures where occupants have virtually no control over the in-vironment. More often than not, windows cannot be kept open or exhaust fans switched on. One cannot also   leave the room if a colleague has severe cold and cough.

In a conditioned space, often free passage of air is limited, with little or inadequate fresh air ventilation. This produces an indoor air environment with relatively high levels of contaminants, bacteria, fungi and dust. The indoor air, thus, has all of the pollutants of the outdoor or surrounding air and also those, that are generated within the building by people and their activities like smoking, hair sprays, cleaning products, paints and pesticides spray residues, carpeting, copy machines and air-conditioning coolants. As a result, the indoor air ends up in most spaces with greater concentration of some pollutants than that is present in the outdoor air. The composite effect of multiple pollutants can seriously impact human respiratory systems leading to various short term and long term illness.

The origins of poor IAQ can be traced to the 1970’s when energy conservation was the only focus. This resulted in tighter with recirculated air for building ventilation and minimum amounts of fresh air being brought into commercial buildings. This minimized the amount of air to be heated or cooled and hence conserved on energy. Ventilation for comfort began to compete with ventilation for health.  This resulted in a situation described as the 'Sick Building Syndrome' (SBS), a term which is used to describe the presence of acute non specific symptoms in the majority of people, caused by working in buildings with an adverse indoor environment.

Increasing the ventilation rate and air distribution rate is a good and cost effective way of reducing indoor pollutant level. At the minimum, heating, ventilating and air conditioning systems should be designed to meet ventilation standards in local building codes. Advanced designs of new buildings can feature mechanical systems that bring outdoor air into the conditioned space. Some of these designs include energy efficient heat recovery ventilators.

Desiccant Rotors International . . . DRI, an ISO certified company is a global provider of components, products and systems for fresh air ventilation, energy recovery, evaporative cooling, humidification, RH control and green buildings. DRI product range includes Energy Recovery Ventilators (ERVs) and Treated Fresh Air Units (TFAs) incorporating the EcoFresh Heat Wheels for Fresh Air Treatment & IAQ. They also provide Evaporative Cooling Pads for Humidification/ Evaporative Cooling & ARCTIC Coolers incorporating EcoCool Pads for cooling large spaces.

DRI's "Green" products help optimize energy performance of the air conditioning systems. This results in a considerable reduction of installed tonnage, reduction in utility bills for the product`s entire life cycle, enhanced IAQ and productivity and reduced health risks. It also helps us procure rating points for energy certification programs like Greenstar and LEED.

Other Group
& Drying
  Dry Air On Rent   Compressed Air Drying   Compressed Air Drying   IT Portals