Chapter 12 Operating Communications

General

Communications on the site are important aspects to the safety and efficiency of a tunneling project. This communication system should connect all major workplaces and safety-critical locations as well as the emergency services from the site (BS 6164: 18.1).

Communication Systems

General

The person in charge of the workplace should be able to give warning of unexpected hazards and receive instructions. The potential hazards and the speed of operations should be considered as the main factor when designing voice communications systems.

When a signal code has been adopted, the details should be posted for any person entering the construction site at the entrances and exits as well as in clear view of the operator.

Tests or adjustments to the communication systems should be made to ensure that messages can be clearly transmitted. Also, the system should be independent of the main tunnel power supply and should be able to withstand mechanical or fire damage (BS 6164: 18.2.1).

Precautions in the Presence of Explosives

Special attention should be placed with radio communication equipment where blasting is being carried out by the use of electro-explosive devices, this includes the use of mobile phones.

A system to ensure that any equipment coming onto the site that emits electromagnetic waves which should not interfere with the equipment operating on site should be put in place, and the details of the frequencies such equipment is operating on should be made available (BS 6164: 18.2.2).

Use of Mobile Phones

A policy and procedure should be put in place for the use of mobile phones underground. Mobile phones emit increasingly strong signals when they are unable to find a base station, e.g., when they are located underground, increasing the risk of interference with equipment (BS 6164: 18.2.3).

Signals

General

A safety sign should be set in place and should be used when the significant risk to health and safety cannot be avoided by the engineering control implemented in place (BS 6164: 18.3.1).

Audible Signals

Audible signals should be considered for routine operations. They should be distinctive and sufficiently loud to avoid confusion. Bells, whistles and air horns are among the most commonly used, and these are the recommended codes (BS 6164: 18.3.2):

Stop one signal.
Lower: two signals.
Hoist: three signals.
Hoist personnel: four signals.
Emergency: continuous

Visual Signals

Signals to machinery and equipment operators should only be given by competent or authorized personnel. These signals should be made familiar to all persons involved in the operations.

Light signals should utilize the same codes as audible signals (BS 6164: 18.3.3).

Closed-Circuit Television (CCTV)

CCTV should be used to assist an operator to monitor or control operations from a place of safety. This can be used with or without sound.

Depending on the location the CCTV is being used at, the system should be able to operate in color and infrared modes (BS 6164: 18.4).

MUST KNOW

Alberta Occupational Health and Safety Code Relevant to the Topic

According to the Alberta Occupational Health and Safety Code (current as of January 1, 2019) an employer must follow the following:

According to Part 5, Section 48(1)(f)

An employer must ensure that a communication system is established that is readily available to workers in a confined space or a restricted space and is appropriate to the hazards.

According to Part 6, Section 108(2)

An employer must ensure that an underground shaft hoist

(a) has a communication system available and working at all times between the hoist operator and workers at landings in the shaft leading to a tunnel or an underground space, and

(b) the controls of the communication system can be operated at all times at every landing in the shaft, on the hoist platform and at the operator’s position.

According to Part 6, Section 108(4)

An employer must ensure that, if a code is used in a communication system in an underground shaft hoist, the code is prominently posted at all times at every landing in the shaft and at the operator’s controls.

AOHS Part 11: 179

An employer and prime contractor must ensure that an emergency communication system is in place for workers to summon first aid services.

According to Part 28, Section 394(1)

An employer must, for any worker working alone, provide an effective communication system consisting of

(a) radio communication,

(b) landline or cellular telephone communication, or

(c) some other effective means of electronic communication that includes regular contact by the employer or designate at intervals appropriate to the nature of the hazard associated with the worker’s work.

According to Part 28, Section 394(1.1)

Despite AOHS Part 28: 394(1), if effective electronic communication is not practicable at the work site, the employer must ensure that

(a) the employer or designate visits the worker, or

(b) the worker contacts the employer or designate at intervals appropriate to the nature of the hazard associated with the worker’s work.

According to Part 6, Section 71

An employer must ensure that hand signals necessary to ensure a safe hoisting operation are given in accordance with AOHS Part 12: 191 by a competent signaller designated by the employer.

According to Part 6, Section 85(1)

An employer must ensure that

(a) if a signal system is used to control the movement of a material hoist the signal descriptions are posted at each floor or level and at the operator’s station,

(b) the operator of a material hoist, and a designated signaller at the floor or level where loading and unloading is being performed, maintain visual or auditory communication with each other at all times during loading and unloading, and

(c) if an electrical or mechanical signal system has been installed to coordinate the movement of the hoist’s skip, platform or cage, the system is arranged so that the hoist operator knows from which floor or level a signal originates.

According to Part 6, Section 85(2)

An employer must ensure that a material hoist erected at a building that is more than 20 metres high has a signal system that

(a) is installed at each floor or level and at the operator’s station,

(b) is designed to allow voice communication between a worker at any floor or level and the operator, and

(b) informs the operator from which floor or level the signal originates.

According to Part 19, Section 264(2)

An employer must ensure that the lights on earthmoving construction machinery installed on or after July 1, 2009 complies with SAE Standard J1029 (2007), Lighting and Marking of Construction, Earthmoving Machinery.

According to Part 5, Section 56(1)

For every confined space or restricted space entry, an employer must designate a competent worker to be in communication with a worker in the confined space or restricted space.

According to Part 5, Section 56(4)

An employer must ensure that the tending worker under AOHS Part 5: 56(3)

(a) keeps track at all times of the number of workers inside the confined space,

(b) is in constant communication with the workers inside the confined space, and

According to Part 6, Section 108(2)

An employer must ensure that an underground shaft hoist

(a) has a communication system available and working at all times between the hoist operator and workers at landings in the shaft leading to a tunnel or an underground space, and

(b) the controls of the communication system can be operated at all times at every landing in the shaft, on the hoist platform and at the operator’s position.

According to Part 6, Section 108(3)

An employer must ensure that in an emergency an additional means of communication is available and working at all times between the operator of a shaft hoist and workers at the face of the tunnelling operations.

According to Part 6, Section 108(4)

According to Part 40, Section 803

A utility employee stringing or removing communication lines or cables near any electric utility facility must ensure that

(a) the limit of approach distances required by Rule 4-130 of the Alberta Electrical and

Communication Utility Code between the communication lines or cables and energized equipment or lines are met,

(b) the communication lines or cables are prevented from contacting overhead electrical lines,

(d) the work method is acceptable to the operator of the electric utility system.

Here are some practices from mining specified in the AOHS and relevant to tunneling:

According to Part 36, Section 644(1)

An employer must ensure that the blast area is clearly identified by posted signs or flagging.

According to Part 36, Sectrion 644(2)

An employer must ensure that unauthorized mobile equipment, vehicles and workers do not inadvertently enter a blast area.