Noise standard.
Houston Code of Ordinances § 9-323
in effectSec. 9-323. - Noise standard.
(a) Prior to the granting under this article of any license, other than a temporary license or a restricted license, the director shall take, or cause to be taken, a measurement of the ambient noise level at the proposed location.
(b) For purposes of this section, the ambient noise level shall be defined as the totality of the background noise in a given place and time, composed of sounds from various sources at various distances, exclusive of the noise emitted by the operation of the helicopter in flight. The ambient noise level shall be determined by measurements, taken during the proposed hours of operation, using a conventional or integrating sound level meter, at a minimum of two locations. Such locations shall be the two nearest churches, schools or residences. Each measurement shall be taken outdoors at the location's property boundary closest to the proposed heliport or helistop.
(c) The estimated noise to be emitted by each proposed helicopter operation specified in the license application will be measured at the same locations used to measure the ambient noise level. All measurements shall be made with the helicopter operating under normal operating conditions and while the helicopter is simulating normal operating procedures, and utilizing all operating modes applicable to the site, including, but not limited to, ingress, egress, hover and fly-over.
(d) The director shall then calculate, based on the formula in subsection (e), the effect of the helicopter operations on the ambient noise level at the locations specified in subsection (b) of this section. The estimated increase of noise level as a result of the proposed helicopter operations shall not exceed the ambient noise level by more than two dBA. If the proposed helicopter operation increases the ambient noise level by more than two dBA, then the license shall be denied.
(e) Formula:
L eq = 10 log (10 Lamb/10 + | H × T × 10 L/10 )
_____ SO
Where:
Lamb = | Ambient noise level in dBA over the period of operations, without helicopters.
Leq = | Ambient noise level reflecting the operational helicopter noise impact.
H = | Number of daily helicopter operations where one operation consists of a landing and takeoff.
T = | Time duration of each helicopter noise operation (seconds).
L = | L eq of each helicopter operation in dBA.
SO = | Number of seconds in period of operations.
(f) If the proposed facility is located within 2,400 feet of an existing facility, then in addition to the specifications set out in 9-323(b), the measurements taken to establish the baseline ambient noise level shall be taken when the pre-existing facility or facilities are not in active operations, and in addition to the specifications set out in 9-323(c) the measurements taken shall be taken during active operations at the pre-existing facility or facilities.
(Ord. No. 2015-1103, § 2(Exh. A), 11-10-2015)
Source: City of Houston, Code of Ordinances and City Charter (Municode Library, library.municode.com)URL: https://library.municode.com/tx/houston/codes/code_of_ordinances?nodeId=COOR_CH9AV_ARTVHEHE_S9-323NOSTFetched: 10/26/2026