BS EN 61779-1:2000

1 General
  1.1 Scope
  1.2 Normative references
2 Definitions
  2.1 Gas properties
  2.2 Types of instruments
  2.3 Sensors
  2.4 Supply of gas to instrument
  2.5 Signals and alarms
  2.6 Times
  2.7 Miscellaneous
3 General requirements
  3.1 Introduction
  3.2 Construction
4 Test methods
  4.1 Introduction
  4.2 General requirements for tests
  4.3 Normal conditions for tests
  4.4 Test methods
5 Field calibration kit
6 Information for use
Annex A (normative) Flammability limits (i.e. LFL and UFL)
                    of some flammable gases and vapours
Annex B (informative) Determination of time of response
Annex C (informative) Bibliography
Annex ZA (normative) Normative references to international
                     publications with their corresponding
                     European publications

Gives general requirements for the construction and testing and describes the test methods applicable to portable, transportable and fixed apparatus for detecting and measuring flammable gas or vapour concentrations with air. The apparatus, or parts of apparatus are meant for use in potentially explosive atmospheres and in mines susceptible to firedamp. This standard is supplemented by the following standards: IEC 61779-2, IEC 61779-3, IEC 61779-4 and IEC 61779-5.

Applies to electrical and electronic apparatus intended for use in residential, commercial and light-industrial environments. Immunity requirements in the frequency range 0 Hz to 400 GHz are covered. No tests need to be performed at frequencies where no requirements are specified. This generic EMC immunity standard is applicable if no relevant dedicated product or product-family EMC immunity standard exists. This standard applies to apparatus intended to be directly connected to a low-voltage public mains network or connected to a dedicated DC source which is intended to interface between the apparatus and the low-voltage public mains network. This standard applies also to apparatus which is battery operated or is powered by a non-public, but non-industrial, low-voltage power distribution system if this apparatus is intended to be used in the locations described below. The environments encompassed by this standard are residential, commercial and light-industrial locations, both indoor and outdoor. The following list, although not comprehensive, gives an indication of locations which are included: - residential properties, for example houses, apartments; - retail outlets, for example shops, supermarkets; - business premises, for example offices, banks; - areas of public entertainment, for example cinemas, public bars, dance halls; - outdoor locations, for example petrol stations, car parks, amusement and sports centres; - light-industrial locations, for example workshops, laboratories, service centres. Locations which are characterised by being supplied directly at low voltage from the public mains network are considered to be residential, commercial or light-industrial. The immunity requirements have been selected to ensure an adequate level of immunity for apparatus at residential, commercial and light-industrial locations. The levels do not, however, cover extreme cases, which may occur at any location, but with an extremely low probability of occurrence. Not all disturbance phenomena have been included for testing purposes in this standard but only those considered as relevant for the equipment covered by this standard. These test requirements represent essential electromagnetic compatibility immunity requirements. Test requirements are specified for each port considered.