742                               LAWS OF MARYLAND                         CH. 450

(3) Regulations, (i) Height Limits. Except as otherwise pro-
vided in these regulations or Sections 11 to 25 and the county reso-
lution aforementioned, no structure or tree shall be erected, altered,
allowed to grow, or maintained in any district established by these
regulations to a height in excess of the height limit herein estab-
lished for such district. The datum plane for measurements of such
shall be mean sea level as established by the U. S. Coast & Geodetic
Survey. The definitions of "structure" and "tree" as set out in said
Sections 11 to 25 and the like resolution of the County Commissioners
of Anne Arundel County dated January 1, 1945, shall be applicable.
SECTION (N) (7) AND (8) SHALL BE APPLICABLE.

(ii) Approach Zone Districts. A. The height of any structure
or tree within the inner area of any approach zone district shall not
exceed one foot of height for every fifty (50) feet measured on the
ground. Measurements shall begin from the end of the runway at
the location and elevation shown on the map and along the center-
line of the approach zone district to a point on said centerline at
right angles to the structure in question.

B. The height limit of any structure or tree within the outer area
of any approach zone district shall not exceed two hundred and
eighty (280) feet above mean sea level.

(in) Transition Zone Districts. A. The height of any structure
or tree within a transition zone district shall not exceed the sum of
(a) the height permitted in the adjoining approach zone district at
a point on its centerline at right angles to the structure or tree in
question, plus (b) one (1) foot of height for each ten (10) feet such
structure or tree is distant from the side boundary of the adjoining
approach zone district measured horizontally along a line perpendicu-
lar to the centerline of the adjoining approach zone district, but no
structure or tree shall exceed two hundred and eighty (280) feet
above mean sea level.

(iv) Turning Zone District. A. The height of any structure or
tree within the turning zone district, which shall include all that land
within four (4) miles from a point within the airport proper whose
Maryland Grid Coordinates are E893,909.99-N490,279.30, and which
is not included in an approach or transition zone district shall not
exceed two hundred and eighty (280) feet above mean sea level.

(v) Overlapping Districts. A. Where districts overlap, the height
permitted shall be that of the district having the most stringent
height regulation.

(s) Use Restriction. Except as otherwise provided in these regu-
lations and Sections 11 to 25, inclusive, and the county resolution
aforementioned, it shall be unlawful to put any land located within
any zone hereby created to any of the following prohibited uses:

(1)  Transformer stations;

(2)  High-tower transmission lines;

(3)  Manufacturing establishments or other uses which produce
smoke interfering with the safe use of the airport;

(4) Rifle ranges and private landing fields which would interfere
with the health, safety, and general welfare of the public in the use
of the airport;