Special Systems - hdbk1132990201

DOE-HDBK-1132-99

control with a combination of timer and photocell should be considered. The

designer should also consider using a backup power source with automatic

transfer switch for street and fence lighting.

In the vicinity of heliports operated by protective force personnel, or near

observatories, light glare should be minimized by selecting the proper fixture.

The installation of aviation warning lights on tall structures adjacent to heliports

should be considered.

2.6

Special Systems.

Standby or emergency power systems should be used to support systems or

equipment components whose operating continuity is determined to be vital by

the design authority for protection of health, life, property, and safeguards and

security systems.

Optional standby systems should be used to power production process

operations if the design authority determines that the process will become

unstable or that a severe monetary loss will result.

The design authority should specify the length of time the emergency power

source is required to maintain full operation of emergency loads. Such power

sources should include built-in features to facilitate operational testing on a

periodic basis to verify readiness.

The source of emergency power may be gasoline engines, batteries,

uninterruptible power supplies (UPSs), diesel engines, fuel cells, propane

engines, hydropower, or gas turbines as determined by capacity, starting duty,

and the life-cycle cost analysis. Steam turbine generators should be used if

steam is being produced for on-site processes.

In many facilities, there are critical loads that are sensitive to fluctuations in the

power supply. There are also loads that should be served continuously if the

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