struction light globe shall be installed on each outside corner of the tower at each level.

(4) All lights shall burn continuously or shall be controlled by a light sensitive device adjusted so that the lights will be turned on at a north sky light intensity level of about 35 foot candles and turned off at a north sky light intensity level of about 58 foot candles.

§ 17.33 Specifications for the lighting of antenna structures over 1,350 feet and up to and including 1,500 feet in height.

(a) Antenna structures over 1,350 feet up to and including 1,500 feet in height above the ground shall be lighted as follows:

(1) There shall be installed at the top of the structure one 300 m/m electric code beacon equipped with two 500- or 620-watt lamps (PS-40, Code Beacon type), both lamps to burn simultaneously, and equipped with aviation red color filters. Where a rod or other construction of not more than 20 feet in height and incapable of supporting this beacon is mounted on top of the structure and it is determined that this additional construction does not permit unobstructed visibility of the code beacon from aircraft at any angle of approach, there shall be installed two such beacons positioned so as to insure unobstructed visibility of at least one of the beacons from aircraft at any angle of approach. The beacon shall be equipped with a flashing mechanism producing not more than 40 flashes per minute nor less than 12 flashes per minute with a period of darkness equal to one-half of the luminous period.

(2) On levels at approximately fourfifths, three-fifths, two-fifths, and onefifth of the over-all height of the tower one similar flashing 300 m/m electric code beacon shall be installed in such position within the tower proper that the structural members will not impair the visibility of this beacon from aircraft at any angle of approach. In the event these beacons cannot be installed in a manner to insure unobstructed visibility of the beacons from aircraft at any angle of approach, there shall be installed two such beacons at each level. Each beacon shall be mounted on the outside of diag

onally opposite corners or opposite sides of the tower at the prescribed heights.

(3) On levels at approximately ninetenths, seven-tenths, one-half, threetenths, and one-tenth of the over-all height of the tower, at least one 100-, 107-, or 116-watt lamp (#100 A21/TS, #107 A21/TS, or #116 A21/TS, respectively) enclosed in an aviation red obstruction light globe shall be installed on each outside corner of the tower at each level.

(4) All lights shall burn continuously or shall be controlled by a light sensitive device adjusted so that the lights will be turned on at a north sky light intensity level of about 35 foot candles and turned off at a north sky light intensity level of about 58 foot candles. § 17.34 Specifications for the lighting of antenna structures over 1,500 feet in height.

Antenna structures over 1,500 feet in height above the ground shall be lighted in accordance with specifications to be determined by the Commission after aeronautical study which will include lighting recommendations. § 17.35

Antenna farms and multiple

structure antenna arrays.

In the case of antenna structures which are so grouped as to present a common potential menace to air navigation, the foregoing requirements for painting and lighting may be modified as a result of aeronautical study. § 17.36 Temporary warning lights.

During construction of an antenna structure, for which obstruction lighting is required, at least two 100-, 107-, or 116-watt lamps (#100 A21/TS, #107 A21/TS or #116 A21/TS, respectively) enclosed in aviation red obstruction light globes, shall be installed at the uppermost point of the structure. In addition, as the height of the structure exceeds each level at which permanent obstruction lights will be required, two similar lights shall be installed at each such level. These temporary warning lights shall be displayed nightly from sunset to sunrise until the permanent obstruction lights have been installed and placed in operation, and shall be positioned so as to insure unobstructed

visibility of at least one of the lights at any angle of approach. In lieu of the above temporary warning lights, the permanent obstruction lighting fixtures may be installed and operated at each required level as each such level is exceeded in height during construction.

§ 17.37 Inspection of tower lights and associated control equipment.

The licensee of any radio station which has an antenna structure requiring illumination pursuant to the provisions of section 303 (q) of the Communications Act of 1934, as amended, as outlined elsewhere in this part:

(a) (1) Shall make an observation of the tower lights at least once each 24 hours either visually or by observing an automatic and properly maintained indicator designed to register any failure of such lights, to insure that all such lights are functioning properly as required; or alternatively;

(2) Shall provide and properly maintain an automatic alarm system designed to detect any failure of such lights and to provide indication of such failure to the licensee.

(b) Shall report immediately by telephone or telegraph to the nearest Flight Service Station or office of the Federal Aviation Agency any observed or otherwise known failure of a code or rotating beacon light or top light not corrected within thirty minutes, regardless of the cause of such failure. Further notification by telephone or telegraph shall be given immediately upon resumption of the required illumination.

(c) Shall inspect at intervals not to exceed 3 months all automatic or mechanical control devices, indicators, and alarm systems associated with the tower lighting to insure that such apparatus is functioning properly.

(b) The time the daily check of proper operation of the tower lights was made, if automatic alarm system is not provided;

(c) In the event of any observed or otherwise known failure of a tower light: (1) Nature of such failure.

(2) Date and time the failure was observed, or otherwise noted.

(3) Date, time, and nature of the adjustments, repairs, or replacements made.

(4) Identification of Flight Service Station (Federal Aviation Agency) notified of the failure of any code or rotating beacon light or top light not corrected within thirty minutes, and the date and time such notice was given. (5) Date and time notice was given to the Flight Service Station (Federal Aviation Agency) that the required illumination was resumed.

(d) Upon completion of the periodic inspection required at least once each three months:

(1) The date of the inspection and the condition of all tower lights and associated tower lighting control devices, indicators and alarm systems.

(2) Any adjustments, replacements, or repairs made to insure compliance with the lighting requirements and the date such adjustments, replacements, or repairs were made.

§ 17.39 Cleaning and repainting.

All towers shall be cleaned or repainted as often as necessary to maintain good visibility.

§ 17.40 Time when lights shall be exhibited.

All lighting shall be exhibited from sunset to sunrise unless otherwise specified.

§ 17.41 Spare lamps.

A sufficient supply of spare lamps shall be maintained for immediate replacement purposes at all times.

§ 17.42 Lighting equipment.

The lighting equipment, color of filters, and shade of paint referred to in the specifications are further defined in the following government and/or ArmyNavy Aeronautical Specifications, Bulletins, and Drawings: (Lamps are referred to by standard numbers.)

$17.43

structures.

(a) All existing antenna structures required to be painted in accordance with the terms of an instrument of authorization dated prior to March 30, 1953, shall be painted in the manner set forth in § 17.23 at the time when the antenna structure is required to be repainted (see § 17.39) or in no event later than January 1, 1960.

(b) All existing antenna structures required to be lighted in accordance with the terms of an authorization requiring only the following lighting specifications shall be changed to the lighting specifications set forth below as soon as practicable or in no event later than one year from the date of the first instrument of authorization that is issued to the station after January 1, 1954:

ment.

Replacing or repairing of lights, automatic indicators or automatic alarm systems shall be accomplished as soon as practicable.

§ 17.45 Report of radio transmitting antenna construction, alteration and/ or removal.

Any permittee or licensee who, pursuant to any instrument of authorization from the Commission to erect or make changes affecting antenna height or location of an antenna tower for which obstruction marking is required, shall, prior to start of tower construction and upon completion of such construction or changes, fill out and file with the Director, U. S. Coast and Geodetic Survey, C. & G. S. Form 844 (Report of Radio Transmitting Antenna Construction, Alteration and/or Removal) in order that antenna tower information may be provided promptly for use on Aeronautical Charts and related publications in the interest of safety of air navigation.

18.77

18.78

18.79

18.80

Effect of certificate of type approval. Changes in type approved equipment.

Withdrawal of certificate of type ap-
proval.

Measurement of field strength.
Location of equipment.

Certification attesting compliance
with rules.

18.81 Renewal of certification.

proval.

Subpart F-FR Stabilized Arc Welders

Technical specifications.

Certification requirements.

Location of certificate.

Subpart H-Miscellaneous Equipment

Miscellaneous equipment.

18.262 Existing epilation equipment.

AUTHORITY: The provisions of this Part 1 issued under secs. 4(1), 303 (r), 48 Stat. 1066 1082, as amended; 47 U.S.C. 154(1), 303(r) Interpret or apply sec. 301, 48 Stat. 1081; 4 U.S.C. 301.

SOURCE: The provisions of this Part 18 ap pear at 28 F.R. 12533, Nov. 22, 1963, excep as otherwise noted.

§ 18.1

Subpart A-General

Statement of basis and purpose

(a) Section 301 of the Communi cations Act of 1934, as amended, provides for the control by the Federal Government over all the channels of interstat and foreign radio communication and further provides, in part, that no person shall use or operate apparatus for the transmission of energy, communications or signals by radio when the effects of such operation extend beyond state lines or cause interference with the transmission or reception of energy, communications, or signals, of any interstate or foreign character by radio, except unde and in accordance with the Communica tions Act and a license granted under the provisions of that act. The operation in the industrial, scientific and medica service of medical diathermy equip ment, industrial heating equipment and miscellaneous equipment of a type which emits radio frequency energy upon fre quencies within the radio spectrum con stitutes a serious source of interference to authorized radio communication serv ices operating upon the channels of in terstate and foreign communication unless precautions are taken which wil prevent the creation of any substantia amount of such interference.

(b) The following rules and regula tions are designed to have a twofold effect:

(1) They set forth the conditions under which the operation of the equipment in question is not regarded as a

cause of interference to the authorized radio communication services and is therefore not required to be operated pursuant to license under the Communications Act.

(2) They provide a procedure for the licensing of medical diathermy, industral heating and miscellaneous equipment which in operation constitute a source of interference to authorized communication services, directly affect the control of the Federal Government over the channels of interstate and foreign radio communication, and are therefore required to be licensed. $18.3 Definitions.

For purposes of the provisions of this part the following definitions in the industrial, scientific, and medical service shall be applicable:

a) "Radio frequency energy" shall include electromagnetic energy generated at any frequency in the radio spectrum between 10 kilocycles and 30,000 megaCycles.

b) "Medical diathermy equipment" shall include any apparatus (other than surgical diathermy apparatus designed for intermittent operation with low power) which utilizes a radio frequency Oscillator or any other type of radio frequency generator and transmits radio frequency energy used for therapeutic

purposes.

(e) "Industrial heating equipment" shall include any apparatus which utitres a radio frequency oscillator or any other type of radio frequency generator and transmits radio frequency energy used for or in connection with industrial beating operations utilized in a manufacturing or production process.

(d) Miscellaneous equipment shall include apparatus other than that defined in or excepted by paragraphs (b) and e of this section in which radio frequency energy is applied to materials to

ace physical, biological, or chemical effects such as heating, ionization of pases, mechanical vibrations, hair removal and acceleration of charged particles which do not involve communicaDons or the use of radio receiving equip

e Ultrasonic equipment shall include y apparatus which generates radio frequency energy and utilizes that energy to excite or drive an electromechanical transducer for the production of sonic or ultrasonic mechanical

Se

assigned by this part for the me of M equipment. A specified tolerance soclated with each EM frequency. § 18.13.)

§ 18.11 Full information: inspection by Commission representatives

Upon request by the Commission the owner or operator of BLT medical de thermy equipment mowa Desig equipment, or miscelated empe shall promptly for the Commusun with such informato LE ILET E TEquested concerning the open I se equipment. The premsa via mDEDical diathermy, mas bag miscellaneous equipment are oper and any license or ceristo zred hereby, shall be available for imper by representatives of the Coremiston 2 all reasonable hours.

§ 18.13 ISM frequencies and frequency tolerances.

The following frequences are Elocated for use by EM eopren will ke tolerance limits specified: