Free software may aid creation of commercial ventilators

A new, free software tool from the National Institute of Standards and Technology (NIST) could help designers develop ventilation systems for commercial buildings.

With the so-called Climate Suitability Tool, building-design teams can evaluate whether the local climate in the US is suitable for cooling a prospective building with natural ventilation, or requires a hybrid system that supplies supplemental cooling capacity.

’We think this tool will be useful during the early stages of design, when decisions on the form of a building and its components are being made,’ said NIST mechanical engineer Steven Emmerich.

’It provides estimates of ventilation rates for preliminary design calculations. You can approximate how many air changes per hour will be necessary to offset heat gains due to the occupants, equipment and lighting so that comfortable conditions are maintained.’

Results include an estimate of the total number and percentage of hours that direct ventilation would be effective over the total for the year, as well as the percentage of hours for which ambient conditions would be too cold, hot or humid for direct ventilation.

It can also show the total number of days requiring night-time cooling and the estimated percentage of days for which night-time cooling would be effective.

The Climate Suitability Tool can be accessed at: