Don't Downplay Human Health Priorities

Don’t Downplay Human Health Priorities

I very much appreciate your recognition of the need for and efforts to identify priorities for “green building” (whatever that is). Such priorities can either be defined implicitly by the buildings a “green designer” creates or by some systematic process based on a hierarchy of environmental problems. Your September/October 1995 feature article reflects the priorities for ecological risks established by the EPA’s Scientific Advisory Board (SAB) in the “Reducing Risk...” report. Yours is an important step in the right direction, and I applaud you for it. Far too many claims of “green design” remain unsupported by any such analysis. Mostly, we building professionals tend to do what we know how to do, what we think is the right thing to do, and what our clients are willing to let us do.

The EPA’s SAB actually had two lists of environmental problems, ecological risks and human health risks. Both types of risks must be considered together in setting priorities. The human health risks were listed as follows (not in rank order):

•Indoor air pollution

•Outdoor air pollution

•Worker exposure to industrial or farm chemicals

•Pollutants in drinking water

•Pesticide residues in food

•Toxic chemicals in consumer products

Clearly,

EBN is aware of the human health risks and devotes substantial editorial space to designs, products, and techniques that can address them.

We have been involved in the NIST/EPA BEES team project described in the same issue. Our (Hal Levin & Associates’) role has been scoping the impacts of buildings on the environment and developing methods for weighting environmental problems based on the prioritization of environmental risks (ecological and human health). We have tried to go beyond the EPA SAB list, since there have been more recent, more complex analyses performed. In particular, we have benefited from various efforts to prioritize environmental risks, and we have added a focus on buildings’ contributions. Note that any effort to create such a list is plagued by the complexity and interconnectedness of environmental problems and a significant lack of scientific knowledge on many of them. We have taken the four criteria used by the SAB and added two of our own to create the criteria set used in our ranking of environmental risks. Our criteria follow:

Criteria for Priority Ranking of Building-Related Environmental Problems

Global, regional, local (large scale being worse than small)

2.The severity of the hazard

The more toxic substances being of more concern, and irreversible changes, such as death or species extinction

3.The degree of exposure

Well-sequestered substances being of less concern

4.The penalty for being wrong

Longer remediation times being of more concern than shorter times

5.The status of the affected sinks

An already overburdened sink is more critical than a less-burdened one (sinks = receptors, environmental compartments)

6.The relative contribution of buildings

Large share of building-related in- or out-flows being worse

In spite of the limitations, I feel comfortable offering designers and their clients advice based on our analysis to date. Noting that the results of our efforts are still preliminary, we suggest the following list of prioritized risks as a basis for focusing designs intended to be less environmentally destructive.

Ecological problems

Top priority env’l problems:E1)Reduction of biodiversity through habitat destruction (especially deforestation)

E2)Global warming

E3)Ozone layer depletion

Medium priority env’l problems:E4) Acid deposition

E5)Urban air pollution/smog

E6)Depletion of groundwater

E7)Surface water pollution

E8)Soil degradation and erosion

E9)Depletion of minerals (especially oil and some metals)

E10)Soil and groundwater pollution

Major human health problems:

HH2)Outdoor air pollution

HH3)Worker exposure to industrial or farm chemicals

HH4)Pollutants in drinking water

Note that we have dropped “toxic chemicals in consumer products” since it is not as directly building-related. Its impacts in buildings tend to be manifested in indoor air pollution.

Using available life-cycle analysis inventory data, one can calculate the impact on each ecological and human health problem. If no prioritization or ranking is done, then, by default, all problems will be weighted equally in a systematic assessment of a material, product, or building design. The NIST/EPA model is intended to eventually provide an analysis based on the prioritization and weighting of various environmental problems.

Of course, such weighting schemes can become even more elaborate if human value choices are considered or if efforts are incorporated to calculate

real environmental costs. For example, a recent study determined that the dollar value of electric power plant operations in New York state was roughly equal to the current price of the energy itself. This analysis was based on only one of many economic tools that have been created for assessing the value of environmental resources, pollution, and encroachment. Differing human moral and ethical perspectives dictate whether we value the spotted owl or the old growth redwood more than the products that can be produced by harvesting certain forests.

Rigorous weighting criteria can be established based on

sustainability analysis such as has been completed by an advisory commission to the Dutch government. Using true sustainability criteria would result in a radical shift in current

green building endeavors.

The reality is that sustainable design and sustainable buildings are far beyond the understanding of current practice, although we can hardly afford to wait much longer before performing the transformation of “green building” into “sustainable building.” We hope our contribution to the NIST and EPA model BEES team effort will provide direction to those seeking to understand and create sustainable buildings. Meanwhile, we encourage your readers to establish clear priorities based on the relative importance of environmental problems. Our preliminary analysis suggests the following design/building actions reflect our prioritization of environmental problems:

•Select durable materials and building systems.

•Re-use (and provide for the re-use of) building materials directly where possible.

•Use recycled materials only if they clearly can perform as well or better than alternatives and no re-usable materials are available.

•Design energy conserving buildings.

•Use energy sparingly and efficiently.

•Create buildings that meet users needs to provide for the longest useful life.

We will continue to evolve our recommendations as our work continues, both as part of the EPA team and also as we consult to architects and building owners in the efforts toward sustainable design. We hope this will contribute to the dialogue you have initiated with your important article, and we look forward to further developments and comments.

Hal Levin, Research Architect

Hal Levin & Associates

Santa Cruz, California