When an inventor develops a product, they will often patent the product to make sure no one else develops the same thing and takes credit for it. Are you wondering whether someone has made a device similar to the one you want to make? You can see if the idea has been patented by searching in InnovationQ Plus, Derwent, or the US patent database.
Patent search tool (slightly harder to use than the others).
When someone makes a new product, they have to make sure it follows the standards for that type of product. Are you wondering what published standards there are for the product you want to make? You can see what regulations exist by searching in the IEEE database or on the ASTM website.