NFPA 99-2012, section 5.1.3.5.15.2 (7) states: EOSCs shall consist of… “Minimum of 1 m (3 ft) of clearance around the EOSC for connection of temporary auxiliary source.”

Does this mean on all sides, including elevations, as in the connection must be 3’ above finished grade? Or does this mean a service clearance of 3’ in front of the EOSC?

Jill I think it is great that you asked this question early in the design process. Not only do you need to consider the clearance around the connection but the location of the EOSC. I have seen the EOSC near receiving areas and Emergency areas. If this is a small facility where the supplier is going to use portable cylinders (high pressure or Dewars) this is not a problem. For larger facilities where the temporary system is installed on a flatbed truck I have seen several common problems such as; shutting down the receiving areas, blocking vehicle access to the emergency areas, and extremely long temporary piping runs between the EOSC and the temporary unit. These larger temporary systems are usually over 20k/scf of product. This means the selected site needs to comply with the exposure hazard requirements in chapter 9 of NFPA 55.