Washington Administrative Code › Title 468 - Transportation, Department of (See Title 88) › Chapter 468-240 - Obstruction marking and lighting › LIGHTING › Section 468-240-195 - Obstruction lighting standards - Prominent buildings and similar extensive obstructions

Current through Register Vol. 24-14, July 15, 2024
(1) Prominent
				buildings and similar extensive obstructions should be lighted in accordance
				with the following specifications. In the event the individual objects of a
				group of obstructions are approximately the same over-all height above ground,
				or water if so situated, and are located not more than 150 feet apart, the
				group of obstructions may be considered an extensive obstruction and so
				lighted.
(2)
Specification
				"E-1."
When the particular obstruction is not more than 150 feet in
				over-all height above ground, or water if so situated.
(a) If the obstruction is not more than 150
				feet in either horizontal dimension, there should be installed at approximately
				the highest point or edge at each end of the major axis of the obstruction at
				least one light, consisting of a lamp of at least 100 watts, enclosed in an
				aviation red obstruction light globe. These lights should be positioned so as
				to insure unobstructed visibility of them from aircraft at any normal angle of
				approach, and to indicate the general extent of the obstruction; or, if the
				shape of the obstruction is such as to make this manner of lighting
				impracticable, there may be installed two such lights at the approximate center
				of the highest point or edge of the obstruction. Both lights should burn
				simultaneously and be so positioned as to insure unobstructed visibility of at
				least one of the lights from aircraft at any normal angle of
				approach.
(b) If the obstruction is
				more than 150 feet in one horizontal dimension, but not more than 150 feet in
				the other, there should be installed at least one light, consisting of a lamp
				of at least 100 watts enclosed in an aviation red obstruction light globe, for
				each 150 feet, or fraction thereof, or the over-all length of the major axis of
				the obstruction. At least one of these top lights should be installed on the
				highest point or edge of each end of the obstruction, with the additional
				lights as required spaced at approximately equal intervals not exceeding 150
				feet, on the highest points or edge between the end lights in a manner to
				indicate the extent of the obstruction and to insure unobstructed visibility of
				the lights from aircraft at any normal angle of approach. If there are two or
				more edges of the same height on such an obstruction located near a landing
				area, the edge nearest the landing area should be lighted.
(c) If the obstruction is more than 150 feet
				in both horizontal dimensions, there should be installed at least one light,
				consisting of a lamp of at least 100 watts enclosed in an aviation red
				obstruction light globe, on the highest point of each corner of the
				obstruction. In addition, there should be installed at least one similar light
				for each 150 feet, or fraction thereof, [if] the distance between the corner
				lights exceeds 150 feet. These additional lights should be installed at
				approximately equal intervals, at the highest points along the outer edges of
				the obstruction, between the corner lights in a manner to indicate the general
				extent and definition of the obstruction and to insure unobstructed visibility
				of the lights from aircraft at any normal angle of approach.
(d) In the event there are one or more points
				within the outer edges of the obstruction, the uppermost parts of which are
				higher than the highest level of the lights hereinbefore prescribed, at least
				one similar light should be displayed from the top of each such point.