Scale forms when dissolved minerals (generally calcium carbonate) and other solids in the water crystallize on surfaces. This further reduces the system’s efficiency by clogging water paths and insulating heat-transfer areas: a 1/32" (0.8 mm) layer of scale can increase energy use by close to 10%. Evaporation exacerbates scale formation, and adding make-up water introduces more minerals to the process. This is partially controlled by “blow-down,” a process of replacing some of the solids-laden recirculating water with make-up water.

Treating cooling-tower water to prevent biological fouling, scale, and corrosion is a complex, highly monitored process. Most of the dirty work in the half-million cooling towers in the U.S. is accomplished with biocidal, conditioning, dispersant, and scale-inhibiting chemicals, including chlorine, various brominated compounds, phosphates, molybdenates, acids (including sulfuric acid), and zinc compounds (which are now banned for cooling-tower use in about half of U.S. states). While chemicals do get the job done, there are considerations beyond the tower. Regulations are increasingly stringent for chemical storage, handling, and disposal; in many jurisdictions, chemically treated cooling-tower blow-down water itself is regulated. There are also consequences to worker, public, and environmental health due to accidental spills, chronic chemical exposure (even at low levels), and bioaccumulation of persistent chemicals in the food chain. Reducing or eliminating chemical usage in the treatment of cooling-tower water is an appealing thought.

Lithium-ion batteries can be configured into higher voltage than NiCad without a significant weight penalty. The V28 technology delivers increased power and up to twice the run time of NiCad with no additional battery weight, according to Milwaukee. This battery technology also operates successfully over a wider temperature range (both hotter and colder) than NiCad, and provides more consistent, fade-free power throughout the discharge cycle. A built-in “fuel gauge” shows how much power remains.

While the avoidance of cadmium means that recycling is not mandatory—as it is with NiCad batteries in many states—Milwaukee still encourages the recycling of all rechargeable battery packs.

As with other IEQ problems in our buildings, it makes sense to reduce sources of this “contamination.” Because sources of noise are often beyond our control, however (nearby highways, overhead planes, or a neighbor’s leaf blower, for example), our best option in reducing exposure to noise is often to design wall, ceiling, and floor assemblies that reduce noise transmission.

Toto, the world’s largest manufacturer of toilets and a significant product innovator, has expanded its hands-free EcoPower™ product line to include flush valves for toilets and urinals. EcoPower sensor-activated faucets, introduced in late 2002, use a tiny hydropower turbine generator for operating and back-up power.

Toto’s EcoPower faucet was awarded a 2004 Good Design Award from the Chicago Athenaeum Museum of Architecture and Design.

® in 1969 and since then has developed a wide range of wall, corner, and door guards. In 2002, one of Acrovyn’s biggest customers—Kaiser Permanente, the nation’s largest health maintenance organization—announced that it would begin requiring PVC-free building and finish materials for its new construction projects. As a result, the C/S Group’s Wall Protection Division recently introduced Acrovyn 3000, a wall-protection line featuring a patented, non-PVC, extruded ABS/polycarbonate thermoplastic containing no phthalate plasticizers and no dioxins or furan formers. It also achieves a Class 1 fire rating without the use of brominated or halogenated flame retardants, and, though C/S claims that it is a locally recyclable material, the company also offers a buy-back program.

The performance and appearance of the PVC-free plastic are the same as traditional Acrovyn PVC plastic. The PVC-free line costs 3–10% more.

Kirei™ is a lightweight, formaldehyde-free panel made from waste fiber left over after processing sorghum, a grain crop grown widely in many parts of the world. The product was developed in Japan in the mid-1990s and introduced to the U.S. market in 2003. Kirei is a Japanese character meaning both clean and beautiful, according to Kirei USA president John Stein. In Japan, the product is known as Koryo Board. Its irregular pattern gives the product a unique and attractive appearance. In addition to the sorghum stems, the panels contain two poplar veneers to provide stability.

While the technology is Japanese, most of the product is produced in northern China, where a factory was built in the sorghum-growing region. According to Kirei USA, sorghum is a drought-tolerant plant requiring little fertilizer or pesticide. By utilizing the waste fiber in this way, farmers are able to realize a new form of revenue, says Stein.

A key feature that is particularly relevant to projects going through LEED® certification, but makes sense for every building with ducts, is the integrated strategy for keeping dust and debris out of the duct system. Cardboard dust covers are factory-installed onto the Speedi-Boot and designed for easy removal after construction is completed. Protection of openings into ducts is required for earning LEED IEQ credit 3.1, “Construction IAQ Management Plan – During Construction,” and this system makes obtaining that credit a lot easier.

Speedi-Boot was developed and is marketed by Lance-Larkin™, a Portland, Oregon-based product development and marketing company. Allan Pilger of the company, described the key benefits of Speedi-Boot as fourfold: saving labor on the job site, cutting down on callbacks, saving energy by reducing duck leakage, and improving indoor air quality by keeping ducts clean during construction. “The biggest selling point,” said Pilger, “is that it’s saving time and saving the contractor money.”

Introduced in early 2004, the UltimateAir RecoupAerator 200DX is the only energy-recovery ventilator EBN is aware of that uses a brushless DC, variable-speed, electronically commutated permanent-magnet (ECPM) motor, though the Model SD95+ ERV that Stirling’s current model replaces also used an ECPM motor. The variable-speed motor allows the RecoupAerator to deliver 50 to 200 cubic feet per minute (cfm) (25 to 95 l/s) of airflow very efficiently, even when operating at low flow rates. Its average electrical consumption at 210 cfm is 200 watts; at 70 cfm the consumption is 34 watts. This, along with its very high heat-recovery efficiency (up to 96%), allows this product to achieve Oregon’s highest level of rebate.

“Stirling is the only manufacturer that has elected to use ECPM DC motors in their ERVs or HRVs,” according to Charlie Stephens, a policy analyst with the Oregon Department of Energy. “It’s truly unfortunate that others haven’t done so, because these products often run 24/7, and most of the time at low speed,” he told

To the best of our knowledge, Humabuilt no longer exists, and the products it previously produced are unavailable.

EBN

Vol. 10, No. 3.) Both Schott North America and Japan’s MSK Corporation now offer these products in North America.