Recommended distances when selecting/planning a Data Center

In Data Center Design, Site selection is one of the most critical and the very first step out of all the phases. We mainly focus on 2 sub-areas. Natural and Man-made hazards are taken into consideration. Today, we are going to look at a few Man-made objects and the required minimum distances. 

Man-made object Minimum Distance (KM)
Gas/fuel stations 1.6
High-voltage transmission lines 1.6
Airport runaways 1.6
Small lakes & overflow areas 1.6
Railroads 1.6
Large store complex 1.6
Water storage towers 1.6
Canals 3.2
Harbour & ports 3.2
Lakes & dams 3.2
Quarries 3.2
Radar stations 5
Research laboratories 5
Radio/TV stations 5
Embassies 5
Airports 8
Chemical & Power plants 8
Military stations & installations 13
Nuclear plants 80

Data Center Areas (MDA,IDA,HDA,ZDA,EDA)

Data Center Areas are to facilitate telecommunication cabling and equipment. Those areas can be categorized as below;

  • Entrance Room
  • Main distribution area (MDA)
  • Intermediate distribution area (IDA)
  • Horizontal distribution area (HDA)
  • Zone distribution area (ZDA)
  • Equipment distribution area (EDA)

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Those areas have been logically defined. Physically, those areas could be either separated or within the same spaces. Will discuss bit more in detail


Entrance Room
The entrance Room may include both access provider (SP) and customer (CE) owned cabling. SP demarcation hardware and equipment are being placed in this area. When using multiple entrance rooms, those should be at least 20m apart from each other. Further, entrance rooms should be outside the computer room in order to improve security.


Main distribution area (MDA)
MDA includes the main cross-connect (MC), which is the central point of distribution for the data center cabling system. Below devices are being placed within the MDA

  • Core Routers
  • Core, Spine, and SAN switches
  • High-end network switches
  • PBX, Voice/VOIP Gateways
  • Multiplexers

Every data center should have at least one MDA.


Intermediate distribution area (IDA)
IDA is to support intermediate cross-connects. The IDA is optional and can include LAN or SAN switches.

Horizontal distribution area (HDA)
HDA is the distribution point for cabling to the EDAs. The main purpose is to provide network connectivity to the end devices located in EDA. EDA area consists of below devices/hardware.

  • LAN switches
  • SAN switches
  • KVM switches

Zone distribution area (ZDA)

ZDA is an optional interconnection point within the horizontal cabling between the HDA and EDA

Equipment distribution area (EDA)
EDA is the area allocated for end devices/equipment. These devices could be Computers, Collaboration devices &, etc.