Northern Telecom IBDN User Manual contains an Appendix D titled 
     _UTP Separation Guidelines From EMI Sources_. The values are the
     same as the cabling pathways standard, EIA-569, table 4.8-5.

      Minimum Separation Distance
           from Power Source at 480V or less
     CONDITION                           <2kVA      2-5kVA       >5kVA
     Unshielded power lines or
     electrical equipment in proximity
     to open or non-metal pathways         5 in.     12 in.     24 in.
      (12.7 cm)  (30.5 cm)  (61 cm)
     Unshielded power lines or
     electrical equipment in proximity
     to grounded metal conduit pathway    2.5 in.     6 in.     12 in.
      (6.4 cm)  (15.2 cm)   (30.5 cm)
     Power lines enclosed in a grounded
     metal conduit (or equivalent
     shielding) in proximity
     to grounded metal conduit pathway      -         6 in.     12 in.
         -      (15.2 cm)   (30.5 cm)

     Transformers & electric motors       <------- 40-in (1.02 m) ----->

     Fluorescent lighting                 <------- 12-in (30.5 cm) ---->

     Source: Integrated Building Distribution Network (IBDN) User Manual
     - Northern Telecom, doc # IBDN-UM-9105, 1991.

     The EIA/TIA working group revising the EIA-569 standard is using the
     results of field and lab tests to update the recommendations. The 
     target date for completion is Dec 1995.