Public transport was free in Paris on Monday and half of the city’s cars were forced off the road in a bid to fight pollution.

Anne Hidalgo, the mayor of Paris, said, “I am delighted the state has agreed to put in place a partial driving ban Monday, which I have been requesting for several days.”

Only vehicles with number plates ending in an odd number were allowed, with exemptions for taxis, electric cars and ambulances.

Authorities were planning to ban cars with odd numbers Tuesday, but the scheme was halted following improving forecasts.

Foreign visitors to Paris, including thousands of Britons on holiday, were also permitted to use their cars.

But police patrols were seen booking locals who flouted the ban, forcing them to return home. Meanwhile, Metro trains and buses were full to overflowing as thousands abandoned their vehicles.

Air quality monitors showed concentrations of potentially dangerous particulates in the Paris air were above the recommended maximum. These are created by cars and lorries, heating and heavy industry, and can potentially cause serious health problems.

Though public transport is free of charge to take the sting out of the restrictions, drivers in the capital have protested against the measure, despite it having been used only twice since 1997.

Similar emergency restrictions were last implemented almost exactly a year ago — March 17 — during a particularly bad spike in the pollution levels.

Authorities measure the concentration of particulates with a diameter of less than 10 microns — so-called PM10 — in the air to determine pollution levels.

The safe limit for PM10 is set at 80 micrograms per cubic meter (mcg/m3), with levels in Paris Monday expected to be somewhere between 40 and 55 mcg/m3. The city’s alert level is fixed at 50 mcg/m3.

为对抗污染，本周一巴黎公交免费运营，半数汽车不得上路。

巴黎市长，安妮·依达尔戈说：“我很高兴国家同意在周一实施部分车辆限行，这个要求我已经提了好几天了。”

只有车牌尾数为单数的车辆可以在周一上路， 但是出租车，电动车以及救护车不受限。

巴黎市政府本计划周二禁止车牌尾号为单数的车辆上路，但是这一方案因随后预报会有所改善的天气状况而终止了。

外国游客，包括成千上万来巴黎度假的英国游客，也可以不受限制使用自己的车辆。

不过，路上可见巡警将那些无视禁令的当地人记录在案，并让他们把车开回家。与此同时，地铁列车以及巴士也因人们不能开车而人满为患。

空气质量监测显示，巴黎空气中的潜在危险颗粒浓度超过了容忍上限。这些颗粒物是由汽车、卡车、供热以及重工业产生的，可能引发严重的健康问题。

虽然在这项限制措施期间的公共交通是免费的，但巴黎的驾车者仍然抗议此项措施。尽管从1997年以来，该措施仅实施过两次。

最近一次类似的紧急限制措施正好是一年前3月17日的实施的，当时的污染水平处于峰值。

检测机构会检测直径小于10微米的微

粒，即PM10浓度，并由此判定污染程度。

PM10 的安全警戒线为每立方米80微

克，周一巴黎PM10浓度预计介于40-55微克/立方米之间。

该市规定的PM10警戒水平为50微克/立方米。

   Words to Learn 相关词汇

    【溢出的】yìchū de overflowing be filled or supplied with in great measure

    【猛增】měngzēng spike an abrupt increase or rise