California Code of Regulations
Title 8 - Industrial Relations
Division 1 - Department of Industrial Relations
Chapter 4 - Division of Industrial Safety
Subchapter 13 - Logging and Sawmill Safety Orders
Appendix A - Radio Control Signaling Devices

Radio equipment at cable logging sites which is used primarily for voice communication shall be assigned a frequency separate from radio equipment used primarily to: initiate whistles and other audible signaling devices; control any machine, material handling device, or other equipment hazards to workers.

Frequencies at 72.44, 72.48, 72.52, 72.56, 72.60, 75.44, 75.48, 75.52, 75.56, 75.60, 154.57 and 154.60 megahertz (MHz) are to be retained for channels using coded modulation to provide secure signalling for the purpose of activating signalling devices and machine functions in cable logging with a maximum one half watt output. Voice transmission on these radio frequencies will be limited to emergency situations only.

All radio devices that are tone coded for signal and/or machine functions or used for voice communications, shall meet or exceed the following requirements, specifications, tolerances and tests:

(1) Transmitters and receivers shall be Federal Communications Commission (FCC) type accepted and certified.

(2) Radio coded systems which activate audible signals or machine functions shall transmit and decode only on authorized codes.

(3) The receiver tone signaling threshold sensitivity shall be .35 micro-volt or better to initiate the signal function.

(4) The receiver spurious attenuation shall be no less than 50 dB.

(5) The receiver selectivity shall be more than 60 dB at the adjacent channel.

(6) In tone coded systems the receiver decode tone frequency stability shall not exceed plus or minus (±) .006 (.6 percent) of the assigned tone frequency.

(7) In tone coded systems, the transmitter encoder tone frequency stability shall not exceed plus or minus (±) .006 (.6 percent) of the assigned tone frequency.

(7.5) In systems which use coded modulation other than tone coding, tolerances on modulation/code parameters shall be such as to guarantee security against code falsing and/or interference with systems of the same or different coding format.

(8) Radio systems (transmitters and receivers) shall operate in accordance with the specifications over an ambient temperature range of minus 30°C to plus 60°C.

(9) Switches of transmitters used to send whistle signals or activate equipment associated with high lead, slackline, or skidder systems of logging shall be designed so that two buttons, motions, or a combination of these are required simultaneously to cause activation of the system. Arrangement of the activating switches shall be such that the operator can transmit signals easily by the use of either hand, but cannot easily activate the transmitter accidentally.

(10) All receivers intended to be mounted on or in the yarder or similar equipment shall continue to operate satisfactorily and shall suffer no mechanical damage after being subjected to a series of no less than 10 impacts in each plane (total 30). Each impact shall be no less than 20 g acceleration.

(11) All receivers intended for mounting in the yarder or similar equipment, and all portable transmitters, shall continue to maintain specified mechanical and electrical performance during and after being subjected to vibration of the magnitude and amplitude as prescribed in ANSI/TIA/EIA-603-1992, Section 3.3.4, Vibration Stability, which is hereby incorporated by reference.

(12) All portable transmitters shall continue to maintain specified mechanical and electrical performance after being subjected to the following test:

The equipment shall be dropped once on each of 5 surfaces from a height of 4 feet.

(13) At least one model of each radio system shall be tested, and certified that it meets or exceeds the minimum requirements for performance specified in this Appendix. The model shall be selected at random from stock.

1. Amendment of Appendix A filed 2-6-85; effective thirtieth day thereafter (Register 85, No. 6).
2. Amendment of second and fourth paragraphs filed 5-1-97; operative 5-31-97 (Register 97, No. 18).
3. Change without regulatory effect amending fourth paragraph filed 12-23-97 pursuant to section 100, title 1, California Code of Regulations (Register 97, No. 52).
4. Amendment filed 10-24-01; operative 11-23-01 (Register 2001, No. 43).
5. Change without regulatory effect providing more legible illustrations within Appendix A filed 3-2-2009 pursuant to section 100, title 1, California Code of Regulations (Register 2009, No. 10).

Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.