20 Darton Street, Concord, MA 01742 / 978-369-5680
Helping Clients Achieve Healthy and Productive Indoor Environments


Consulting services are provided to evaluate the performance and condition of the HVAC system, the building, and nearby sources as they relate to the achievement of good Indoor Environmental Quality (IEQ).

Specific testing services include:

Carbon dioxide (CO2) monitoring: Continuous multi-point monitoring of CO2 concentrations provide operational feedback on the amount of ventilation actually provided to building occupants. Research by Milton has shown that providing more ventilation than called for in ASHRAE’s Standard 62 can be cost effective by reducing the short-term absenteeism of employees and thereby raising their productivity. Testing can involve just a few monitoring locations, or as many as 48 with equipment by AIRxpert Systems, Inc.

Tracer testing: Tracer testing potentially provides useful information on building and HVAC performance in several ways. Tracer testing can provide details about pathways of air movement within buildings that allow odors to show up where they are not intended or appreciated. Tracer gas testing can also quantify ventilation rates in buildings that have been evacuated. (see Tracer Gas Testing Service)

Particulate testing: Testing of particulate levels can potentially provide useful information on the performance of the HVAC system by quantifying the capture effectiveness of the filtration system and objectively assessing whether the ductwork should be cleaned.

Pressure mapping and air flow pattern determination: Another assessment technique for improving the understanding of building performance is the measurement of pressure relationships around the building and the resulting air flow patterns.

For information on these aspects of the indoor environment, or other questions about whether a healthy and productive indoor environment is being achieved, please contact David W. Bearg, PE at 978-369-5680 or email

20 Darton Street, Concord, MA 01742-5710

Sage Farm [Energy Efficient Residence]