concessionaires part of the campaign so they can inform visitors of the reason behind the policies. Communicating with communities near park entrances, “friends of the parks” groups, and other stakeholders can build understanding and support of low-noise policies. A website could enable sharing of best practices.

PURCHASING

Because A-weighted sound levels do not adequately capture all impacts of noise, the group urged that parks have multiple mechanisms and multiple criteria to deal with protection of the soundscape, wildlife impact, hearing loss prevention, and community noise. However, in considering multiple metrics, the Park Service should standardize its operations nationwide, as applicable, to ensure consistency and enable vendors to compete under the same terms. Moreover, sound quality (e.g., impulsive, rumbly, or hissy) needs to be considered in addition to sound level, as the latter does not convey all the dimensions of noise’s effects on humans, and visitor perceptions are important.

Noise emission requirements could be included in contracts for maintenance and other services and in purchase specifications for equipment. Standards for noise emissions and guidance for low-noise products have been developed both in the United States and in other countries. A measurement standard included in the specification would enable the Park Service to verify measurements. Some products, particularly those manufactured for sale in the European Union, may already be certified and labeled. For example, the Blue Angel3 label, which certifies products as low noise, is widely used in Europe and covers many tools and equipment of potential interest to the Park Service, such as construction machinery, garden tools, municipal vehicles, and automobile tires. As a specific example, plastic garbage cans are quieter than metal, and there is a Blue Angel label for cans that collect glass. There is also a Blue Angel label for chainsaws.

Data from manufacturers on noise emissions are preferable to data from other sources, according to the group, as they are generally more accurate and more current. The group also discussed identifying the most frequently purchased pieces of high-noise equipment in the Park Service and developing specifications for them first. Bulk purchasing, perhaps across government agencies, could also be a strategy for the

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3 Online at www.blauer-engel.de/en/index.php.



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