Security Lighting. For security lighting criteria, refer to
Section 6 of this manual.
Grounding. Bonding, and Shielding
Description. All grounding and bonding in new electronic
facilities shall conform to MIL-STD-188/124, Grounding, Bonding and Shielding
for Common Long Haul/Tactical Communication Systems, and MIL-HDBK-419. All
shielding and (HEMP) protection shall satisfy the requirements set forth in
the BESEP and MIL-HDBK-1012/2, High Altitude Electromagnetic Pulse Protection
for Ground-Based Facilities. Requirements for specific facilities are set
forth in Section 8 of this manual.
General Grounding Requirements
220.127.116.11 Facility Ground System Requirements. Recommended grounding
practices for a typical electronic facility are illustrated in Figure 8.
These recommended grounding practices can be modified when HEMP shielding is
required and such modifications are provided in the BESEP.
a) Earth electrode subsystem (EES). The EES consists of a network
of earth electrode rods, plates, mats, or grids and their interconnecting
conductors. For a detailed discussion, refer to MIL-HDBK-419, Chapter 2 of
Volume I and Section 1.2 of Volume II.
b) Lightning protection subsystem. This subsystem, consisting of
air terminals, their down conductors, and related suppressors, provides a
nondestructive path to ground for lightning energy contacting or induced in
facility structures. For a detailed discussion, refer to MIL-HDBK-419,
Chapter 3 of Volume I and Section 1.3 of Volume II.
c) Fault protection subsystem. This subsystem ensures that
personnel are protected from shock and that equipment is protected from damage
or destruction resulting from faults. For a detailed discussion, refer to
MIL-HDBK-419, Chapter 4 of Volume I and Section 1.4 of Volume I and Section
1.4 of Volume II.
d) Signal reference subsystem. This subsystem established a
voltage reference and minimizes noise currents in the facility, so that
relative voltage levels are maintained and unacceptable noise voltages not
occur on signal paths or circuits. For a detailed discussion, refer to MIL-
HDBK-419, Chapter 5 of Volume I and Section 1.4 of Volume II.
a) Earth Electrode Subsystem. The basic measure of effectiveness
of an earth electrode is the value in ohms of the resistance to earth at its
input connection. MIL-STD-188/124A specifies 10 ohms as design goal to
satisfy lightning protection requirements. NFPA 78, National Fire Protection
Association's Lightning Protection Code, also recommend 10 ohms.