OSB is available for structural applications and for non-load-bearings uses. In Europe there are four basic grades available.
Manufacturers also offer variants within these grades, for example, sanded and un-sanded, tongue-and-grooved and plain-edged.
Here is a broad guide to which grade you will need for the job in hand:
General purpose applications in dry conditions. Furniture and interior fitments
Load-bearing applications in dry conditions
Load-bearing applications in humid conditions
Heavy-duty load-bearing applications in dry or humid conditions
Technical specifications for these grades are set out in the European standard EN 300 and in OSB manufacturers' users manuals. For details, ask your national standards organisation, trade association, or timber supplier.
OSB delivers the performance of plywood at a lower cost. It even has some important characteristics that give it the edge over veneered boards - like its uniformity, its lack of knots, its resistance to de-lamination, distortion and splitting and, not least, its low impact on global timber resources. All this may come as a surprise if you are one of those who have thought of OSB as just a 'cheap substitute'.
But surely, you may say, plywood is a quality, precision-manufactured product available in a whole range of performance grades? Yes, but so is OSB! In fact, OSB will do the same job at least as well for less cost.