There should always be sufficient space around the logo to keep it clear of distracting elements, such as type, photographs or graphics. In general, this clear space is equivalent to two times the height of the "book" illustrated within the logo.
Because of inherent space restrictions in some specific usages, this space requirement may have to be modified. For example on business cards, banners or signs, the logo may be positioned closer to the edge of the product so long as the logo remains the primary visual.
The logo should always be proportional to the piece being created. The height of the seal should never be less than 5/8 inch. The logotype will always be proportionate to the seal and should not be scaled separately.
As a rule of thumb, the seal should never be smaller than about the size of a dime.