Santa fe is one of only 20 U.S. cities the ALA looked at with consistently safe ozone levels.

圣达菲是美国汽车法律协会(ALA)观察的臭氧水平一贯在安全范围的20个城市中唯一的一个。

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But the ozone layer is not yet safe.

但是即使如此，臭氧层依然没有获得安全保障。

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Ozone as a disinfectant is used extensively in various regions. It is intensely concerned because of its properties of no - residual, no - pollutional, safe and effectual.

臭氧作为杀菌剂广泛应用于各个领域，它以无残留、无污染、安全、高效等特点越来越引起人们的关注。

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