Proactive indoor environmental quality assessments: navigating green building certifications

When constructing or renovating cost-effective, sustainable buildings, it’s important to consider IEQ, or the conditions inside a building and their health effects on occupants. Better IEQ can lead to improved occupant health, well-being, and productivity. IEQ directly affects building occupants and employees across diverse areas from office buildings, hotels, hospitals, schools, and laboratories to industrial manufacturing facilities.

Assessing indoor environments can become complex and include a variety of contaminants such as gases, volatile pollutants, particulates, microbial growth, water quality, light intensity, and hazardous building materials. Indoor temperatures, relative humidity, and ventilation can also affect building occupants’ perception of acceptable IEQ.

These are just some of the challenges building owners and managers face when addressing IEQ in the built environment – in addition to the heightened awareness of building occupants following the Covid-19 pandemic, wildfire smoke, outbreaks of Legionnaires disease, and requirements from numerous green building certifications.

Why perform IEQ testing?

US Environmental Protection Agency (USEPA) studies indicate the potential impact of IEQ on human health can be noteworthy in the US, with approximately 90 percent of a typical American’s time spent indoors, where some pollutant concentrations can be two to five times higher than typical outdoor concentrations. Additionally, many high-risk individuals who spend more time indoors are potentially more susceptible to adverse health effects.

A proactive IEQ testing program can assist building managers with identifying potential building-related issues and taking appropriate corrective actions to maintain a healthy indoor environment.

What common health effects can be attributed to building indoor air quality?

The common reported health effects for building occupants related to indoor air quality include irritation of the eyes, nose, and throat; headaches, dizziness, and fatigue; and other respiratory diseases. However, determining a specific airborne contaminant can be difficult due to the commonality of these symptoms, a variety of contaminants that may be present in the indoor environment, and potential sensitization to agents such as mold or formaldehyde.

Importance of mechanical ventilation

According to the National Institute for Occupational Safety and Health (NIOSH), the most common sources of IEQ issues are related to inadequate ventilation.

Following the pandemic, ASHRAE^® (formerly known as the American Society for Heating, Refrigerating, and Air Conditioning Engineers) and the Centers for Disease Control (CDC) developed guidelines for ventilation that shift toward health-based approaches.

In 2023, the CDC published new guidance focused on improved air circulation, increased ventilation with at least five air changes per hour, post-occupancy air flushing to remove residual contaminants at the end of the workday, more efficient air filtration, and other building-specific ventilation strategies. Although these strategies are a direct result of the Covid-19 pandemic, their utilization as best practices can address infectious aerosols (e.g., the common cold and influenza) and provide additional controls for particulates, allergens, wildfire smoke, chemicals, and construction-related work activities.

Green building standards, certifications, and rating systems

Various national and international agencies have developed green building programs to establish better IEQ in buildings after construction and during occupancy to protect human health, well-being, and productivity. These programs provide an overall improvement of the environment through sustainable design, construction, and maintenance. Each program may include third-party verification and certification fees based on the size of the structure, with various certification levels and specific focus areas.

Examples of widely accepted standards that emphasize IEQ include ASHRAE 62.1-2022, Ventilation and Acceptable Indoor Air Quality and ASHRAE 55-2020, Thermal Environmental Conditions for Human Occupancy. Other common green building certification and rating systems in the US and internationally include US Green Building Council’s Leadership in Energy and Environmental Design (LEED) certification, International WELL Building Institute – WELL Performance or Building Rating systems, Center for Active Design Fitwel certification, and Living Building Challenge certification.

Ramboll can help

Our industrial hygienists, chemists, epidemiologists, toxicologists, and engineers have broad experience partnering with clients to assess air quality in the built environment. We provide expert guidance – including assistance with developing IEQ programs and implementing and achieving certification – for clients to make informed decisions for safe and healthy indoor environments. If IEQ concerns arise, our expertise can often help identify problems, design practical solutions, and communicate with affected stakeholders, including building occupants and property owners and managers.