Where materials handling equipment is present or there are other forces that may overturn the structure suitable fixings are required (SEMA COP Low Rise Shelving § 9).
The frequency of floor fixing depends upon the height to depth ratio of the shelving: With a height to depth ratio of less than 4:1 the shelving can be free standing in the absence of materials handling equipment.
With a height to depth ratio of between 4:1 and 6:1, only the perimeter uprights need be fixed by a bolt through the base plate.
Floor fixings should be designed to carry a shear force of 3Kn and a tensile force of 2Kn. Providing that the fixings satisfy these criteria then they would satisfy the SEMA Code. These fixings should be applied through the base plate of the upright and be capable of resisting the anticipated horizontal shear and vertical uplift forces. Where the height to depth ratio exceeds 6:1 additional restraints are required to other substantial structures providing that they are capable of providing this support.
Our recommendation is to always fit floor fixings where the system permits regardless of actual requirement. Alternatively where a system doesn't permit floor fixing you may want to consider alternatives such as securing to an adjacent structure provided that structure is capable of withstanding any additional imposed forces.