Indoor Air Quality

In May of 2012, the Barnes unveiled its new campus in Philadelphia. In rooms reflective of the intimate layout and unique character of the original galleries, the campus experience includes galleries, classrooms, garden, interior light court, auditorium, library, restaurant, coffee bar, gift shop, and offices.

Designers had several goals when they were planning the building. Environmental conditions were paramount - systems were designed to preserve one of the world's finest collections of art using constantly stabilized temperature and humidity levels in gallery spaces where temperatures of 70° F and relative humidity of 50% are maintained year round. The filtration system needed to protect art collections from harmful airborne particles, chemicals and gases. The system was designed to clean both recirculated indoor air and also ventilation air brought in from the outdoors. Mechanical systems were operated for a nine month period prior to any artwork being moved into the building, to properly condition the environment for the artwork and ensure that systems were operating as designed. Lastly, designers wanted to employ sustainable practices to manage ongoing operating costs.

Electronic Air Cleaning 

Outdoor air in Philadelphia, like all other metropolitan areas, contains vehicle emissions which are composed of an abundance of ultrafine particles (UFPs) and gaseous and volatile compounds. A minimum of MERV 15 filtration is necessary to remove UFPs particles from the air. Electronic polarized-media air cleaners were selected that are capable of exceeding MERV 15. Their active-field mechanisms give them the ability to capture ultrafine particles and adsorbed gas phase contaminants from the outdoor air.

Dynamic V8 Air Cleaning System

 

Activated Carbon

The activated carbon matrix modules were engineered to meet specific performance requirements including static pressure drop, maximum face velocity, residence time, and target contaminants including Ozone, Xylene, Sulfur Monoxide, Sulfur Dioxide, Nitrogen Oxide, Hydrogen Sulfide, Chlorine, Chlorine Dioxide and other acid gases and odors.

Dynamic Activated Carbon Matrix System

Sustainable Design 

Both systems offer very low static pressure resistance relative to conventional filtration methods. Low static resistance saves energy by reducing the fan horsepower required to move air through the central HVAC system. For example a polarized-media electronic air cleaner consumes three times less energy than a MERV 14 cartridge filter with pre-filters. And activated carbon matrix systems offer up to 60% lower pressure drop than traditional pellet systems which can reduce blower horsepower requirements by up to 50%. For the Barnes Foundation, these results are expected to translate into savings of hundreds of thousands of kilowatt hours per year.

The air cleaning systems used will also reduce other ongoing operating costs. The selected air cleaners hold up to ten times more dust than standard cartridge and bag filters. This exceptionally high dust loading means much longer maintenance cycles; where change-out intervals are measured in years instead of months, meaning no quarterly pre-filter change-outs and no nine month final filter replacements. Likewise, properly rotated carbon matrix systems use 100% of the media, unlike pellet based systems which typically break through after about 66% utilization which means longer service intervals. Carbon matrix modules are also easier to use and maintain because they do not require vacuum trucks, pellet handling or confined space entry that is associated with pellet media. These attributes free up a lot of time for maintenance personnel to concentrate on other things. And less media changes means less material usage, fewer disposal costs and a smaller environmental footprint for the building.

At the Barnes, energy modeling was used for the building in a variety of ways to support LEEDŽ Platinum certification. The museum was designed to exceed the performance of the ASHRAE 90.1 energy standard by an impressive 43 percent. In addition to the filtration system, other strategies that contributed to these savings included ventilation-air heat recovery, demand-control ventilation, rooftop solar panels and optimization of the thermal properties of the envelope, such as overhangs and other shading devices that help control heat gain.

18 Months Later

A year and a half after the opening, the filtration systems were evaluated to see how the service life was comparing to projections. Based on static pressure, the polarized-media air cleaners were on track to last over three years, as planned.

An activated carbon module was also analyzed to determine how much carbon had been used. The core sample indicated higher than normal levels of acetic acid, a substance potentially harmful to artwork. Using Google Earth, it was determined that the acetic acid was likely attributable to an unforeseen circumstance. A Whole Foods Market was located nearby. Whole Foods offers a large selection of fresh produce. Unsold produce goes into the dumpsters behind the store. And decomposing produce off gases acetic acid. Fortunately, the analysis identified the threat and a recommended carbon service interval was established to ensure that the system is capable of dealing with it.

KEY PARAMETERS 

• Type of Facility - New Construction
• Function - Art Gallery / Museum / Educational Institution
• Area - three stories, 93,000 sq ft
• Project Cost: $150M
• Project Completed - May, 2012
• LEEDŽ Platinum Certification

TEAM

• Owner - The Barnes Foundation 
• Architects - Tod Williams Billie Tsien   
• Construction Mgmt - L.F.Driscoll Co.  
• Engineers - Altieri Sebor Wieber LLC
• IAQ - Dynamic Air Quality Solutions
• Construction Mgmt - L.F.Driscoll Co.
• Engineers - Altieri Sebor Wieber LLC
• IAQ - Dynamic Air Quality Solutions