Authorities will raise the earthquake-resistant level for new school buildings to be built in the southwestern Chinese city of Chengdu following the devastating May 12 quake, a local official said Tuesday.

The new schools will be designed with a higher-resistance level than usual residential buildings, said Zhou Guangrong, Chengdu Municipal Education Bureau head, at a press conference here.

"The level will be increased by 1 to 2 grades on the quake intensity scale," he said. "Our aim is to make the school buildings capable of serving as safe havens at critical times."

Chengdu planned to complete the construction of 367 new schools before Sept. 1 next year, of which 26 were now under construction, Zhou said.

Almost all the primary school and high schools in the city, 1,086 in total, had resumed classes, he added.

A quake is measured by its magnitude and intensity. The magnitude indicates the amount of energy released at the source, or the epicenter,and is measured by the Richter Scale.

The intensity of a quake at a particular locality indicates the violence of earth motion produced there by the quake. It is determined from reported effects of the tremor on human beings, furniture, buildings, geological structure and others.

Many countries and regions adopt the Modified Mercalli Scale (MMS) that classifies earthquake effects into 12 grades. China also uses a 12 grade intensity scale similar to MMS.

According to Zhou, residential buildings in Chengdu were designed with a resistance level of 7 grades on the intensity scale, which means a quake can cause negligible damage in buildings of good design and construction, and slight or moderate damage in well-built ordinary structures.

A quake of 8 or 9 grades on the intensity scale can lead to considerable damage in specially-designed structures with partial collapse.

The quake, measuring 8.0 on the Richter Scale and up to 11 in terms of intensity, left nearly 80,000 people dead or missing and millions homeless.

The quake also flattened school buildings and claimed the lives of students and teachers.

(Xinhua News Agency June 25, 2008)