Any company wishing to sell solar collectors and systems worldwide must have its products certified in order to obtain whichever certificate is required in a particular region. This is a barrier to being active on the global marketplace. The requirements are now converging, however.
Links:
[1] http://admin.indiaenvironmentportal.org.in/feature-article/towards-one-standard
[2] http://admin.indiaenvironmentportal.org.in/category/author/ina-ropcke
[3] http://admin.indiaenvironmentportal.org.in/category/journal/sun-and-wind-energy
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/solar-energy
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/renewable-energy
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/trade
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/solar-thermal-power