BS 6657:2002 pdf download

BS 6657:2002 pdf download.Assessment of inadvertent initiation of bridge wire electro-explosive devices by radio-frequen cyradiation—Guide.
5.3 ResponsIbility for making the hazard assessment
The radio-frequency (RF) environment is becoming increasingly severe, with the proliferation of transmitting sources and increased transmitter powers and the exploitation of new techniques.
NOTE) UK legislation Ill requires that emptoven. safeguard both their employees and othee. who may he pisce4 at risk by their iu’tivitiem. Hence, both npcissmnn. of RF trnnsmittenm slid eec,. of EED hnvr a r eqi.ibility to issuer safe operation.
NOTE 2 Particular locutions such as mines and quarries may exist where additional responsibihues are placed on die owners mind Inanazees
Operators of a proposed site in which EEl) are to he used should request details from the transmitter operators about relevant transmitters in the locality of the Site. The transmitter operators should include details of transmitters fir broadcast, commercial, military, air traffic and emergency services such as police, fire and ambulance. The site operator should then use the assessment procedures given in this British Standard, if necessary in consultation with Ihe transmitter operators concerned.
Similarly, an operator of a proposed new (or altered) transmitter should contact all operators of sites where LED are used within the minimum distance of safe approach for the transmitter, and use the procedure given in this British Standard to assess the potential hazard at each location.
Where both the site and the transmitter already exist but an assessment is required, the site operator should he held responsible for ensuring that the assessment is made. If for some reason relevant information cannot be made available to the body responsible for the assessment, the responsibility for having the assessment carried out should be assumed by the body unable to release the necessary information.
NOTE As an aid to thos, who need to make a hazard aiw.isnwhIt hut do ot has. th. iwmwssaiy t.chnical fiossufess. a hut of of Information and spedalist organizations capable of providing cuuistikatmoo or test facilities is given in Annea C,
5.4 Recommended practices for radio silence in offshore operations
The position adopted by many offshore operators has been to switch off all transmissions frium the installation during the surface preparation of the explosive tool until its immersion in the well at 70 m below sea bed level. At this point services would be restored until the explosive tool was returned to a similar depth on the upward Journey when all services would again be cut off. Following its removal from the well and inspection to ensure its sife condition, services would be restored provided no further explosive handling was to take place.
However, too gres a reliance on all-embracing curtailment of services can itself present a potential hazard to structures which employ radio communication for safety reasons and as an integral part of product transportation systems (pipelines). The identification of these difficulties has highlighted the need for the hazard to be more accurately quantified in order to minimize the disruption of other necessary operations and to avoid the creation of further potential hazards
6 Transmitters and transmitter output parameters
6.1 Types of transmitters
This clause provides information on various types of transmitter and transmitting systems. This information is necessarily rather brief for certain types of radar and other military equipment but basic details are gven and further information may be sought from the specialist organizations listed in Annex C. Typical types of antenna installations are shown in Figure D.1.
8.2 Frequency range
The main frequency range covered is 9kHz to 60GHz, The types of transmitter considered include the following:
a) radio and television broadcast transmitters in specific bands in the range 0,15 MHz to 1 000 MHz:
b) fixed and mobile transmitters for communication lurpose-s, private, commercial and amateur, in specific bands above 0.4 MHz and for military use above 0.15 MHz:
c) radar, in specific bands at 220 MHz. 600 MHz and above 1 GHz:
d) navigational equipment. non.directional beacons, etc., from 9 kHz upwards.