Certified by any other country? Which?

是否获得其它国家的认证？哪些？

So, why aren't all helmets certified by Snell?

那么，为什么不是所有的安全帽经斯内尔？

Certified by ISO9001 International Quality Control Standard.

获得ISO 9001国际质量管理标准认证。

Since 2007, four countries have been certified by WHO as malaria-free.

自2007年以来，已有四个国家通过世卫组织认证，境内消除了疟疾。

The reliability of the two methods are certified by result of experiment.

实验结果证明了这两种方法的可靠性。