There were 15 minutes between the first air raid alert and the sounding of the all-clear signal.

从第一个空袭警报到警报解除号音其间有15分钟。

During the air pollution red alert, the Beijing Commission of Education ordered all kindergartens, primary schools and middle schools to suspend classes.

在空气污染红色预警期间，北京市教委下令让所有幼儿园、小学和中学停课。

The alert level "is now at a higher class" than in 2002, says Air Force Brig. Gen. Jung Jae-bu, commander of the 20th Fighter Wing.

“目前的警戒水平”高于2002年，第20战斗机飞行中队指挥官，空军准将郑在卜(音)表示。

If pilots keep getting unnecessary alerts, they will tend to ignore them.If an alert is not issued when it should be, however, the result can be a mid-air collision.

如果它不断发出“狼来了”的警告，飞行员将会逐渐无视它的存在，反之，如果紧急关头警报没有及时发出，后果可能是撞机。

If an alert is not issued when it should be, however, the result can be a mid-air collision.

而如果在必要时未能发出预警，其结果就可能是空中撞机。

The Airparif monitoring agency said smog density was still near alert levels Monday, but rain forecast for Tuesday was expected to clear the air.

空气监测机构表示，周一雾霾浓度仍然处于警戒水平，但是预计周二的降雨能够净化空气。

The announcement came last night as Beijing has extended its orange alert forheavy air pollution again as smog is expected to persist until the weekend.

这个宣布来自昨晚，北京再次发布空气重污染橙色警报，预计雾霾将持续到周末。

Passengers traveling by air face a new security alert. Airport screeners are extra-focused on thermos-type insulated beverage containers.

乘坐飞机旅行的乘客面临新的安全警告。机场扫描仪现在更加注意热水瓶性的保温饮料罐。

During the recent red alert, pollution peaked at 508 on Tuesday, according to the US Embassy's air pollution monitoring service in Beijing.

据美国驻北京大使馆的空气污染监测服务中心数据显示，北京红色预警期间，污染在星期二达到峰值508微克。

It also initiated its first-ever air pollution red alert mechanism.

它还启动了首个空气污染红色预警机制。

Some areas in northern China including Beijing will pass New Year's Day under a cloud as the national observatory renewed an orange alert for air pollution on Sunday.

上周日国家天文台公布了新的空气污染橙色警报，这意味着包括北京在内的一些北方地区不得不在阴霾下度过元旦。

The crew failed to lower the landing gear and turned off an alert system, according to the Air Force Times.

船员们没有降低起落架和关闭警报系统，根据空军时报。

Last week, Beijing issued its first ever red alert because of poor air quality, closing schools and restricting traffic.

上周，北京发布了雾霾红色预警，致使多所学校停课，交通限流。

Traffic Alert and Collision Avoidance System (TCAS) plays a more and more important role in flight safety with the constantly increasing air traffic flow.

随着空中交通流量的日益上升，空中交通警戒和防撞系统(TCAS)在保障飞行安全方面的作用越发重要。

The Pakistani air forces meanwhile put Lahore, Sargodha and other forward bases on alert to reduce reaction time.

同时，巴空军已下令包括拉哈尔、萨戈达在内的所有前沿基地进入戒备状态，以减少反应时间。

This is why many air pollution monitors have been set up, because public health authorities want to know if there is a need to issue an alert for bad pollution.

这就是为什么许多城市建立了空气污染监测，因为公共卫生当局想确定是否需要发布环境污染警报。

Beijing has issued and extended an orange alert for heavy air pollution as persistent smog continues to shroud the Chinese capital.

近期雾霾持续笼罩首都北京，北京市发布并延长了空气重污染橙色预警。

I'll play out in the open air, I will be alert and kind and fair.

我要在户外多玩耍，变得机灵友善又美丽。

When a red-alert for air pollution goes into effect, the emergency plan will only allow drivers to use their vehicles every other day on an odd-even license plate system.

概要：《北京市空气重污染应急预案》今天正式发布，市环保局新闻发言人方力表示，空气污染达一级红色预警时，机动车将实行单双号限行。