BS 6656:2002

Committees responsible
Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 Symbols and abbreviations
5 General considerations
6 Transmitter and transmitter output parameters
7 Structure and spark-making mechanisms
8 Ignition of flammable atmospheres
9 Practical measurements and tests
10 Methods of assessment for determining potential RF ignition
   hazards on a plant containing hazardous areas
11 Plant safety measures
12 Special cases
Annex A (informative) Sources of information and addresses of
        some advisory bodies
Annex B (informative) Electromagnetic radiated fields and examples
        of radiating antennas and unintended receiving antenna
        characteristics
Annex C (informative) Subdivision of group II flammable gases and
        vapours
Annex D (normative) Measurement of electromagnetic fields
Annex E (normative) Method of measurement on structures (on-site
        tests)
Annex F (informative) Derivation of vulnerable zone distances for
        Table 5, Table 6 and Table 10
Annex G (informative) Worked examples of full assessment procedure
Annex H (informative) Ground-wave propagation (vertical
        polarization) - Calculation of field strength
Bibliography

Presents guidance on assessing the potential ignition hazard from the inadvertent extraction of energy from electromagnetic fields, propagated from communication, radar or other transmitting antennas to plant where a potentially flammable atmosphere may be present.

This British Standard provides guidance on assessing the potential ignition hazard from the inadvertent extraction of energy from electromagnetic fields, propagated from communication, radar or other transmitting antennas to plant where a potentially flammable atmosphere may be present. The frequency range covered by this British Standard is 9 kHz to 60 GHz. This British Standard does not apply to similar hazards arising from electromagnetic fields generated by other means, such as electric storms, electricity generating installations or other radiating electrical equipment, nor does it apply to any hazard arising within telecommunication or other electronic equipment.

NOTE 1 The methods of assessment from 9 GHz to 60 GHz are based on extrapolation of data for frequencies below 9 GHz.

NOTE 2 The ignition of dust is not covered in this British Standard.

This British Standard also provides advice on how to mitigate the hazard in cases where the assessment indicates that a hazard may exist.

This British Standard does not cover the hazards associated with the use of electro-explosive devices (EED) (see BS 6657), or the biological hazards of exposure to RF fields.