NEN EN 50073 : 1999

Foreword
1 Scope
2 Normative references
3 Definitions
4 Intended application
    4.1 General
    4.2 Performance testing
    4.3 Electrical testing and certification for
          use of apparatus in potentially explosive
          atmospheres
    4.4 Fixed apparatus and fixed systems
    4.5 Transportable apparatus
    4.6 Portable apparatus
    4.7 Sampling lines and sampling probes
    4.8 Filters
    4.9 Flame arrestors
5 Criteria of selection
    5.1 General
    5.2 Catalytic sensor
    5.3 Thermal conductivity sensor
    5.4 Infrared sensor
    5.5 Semicondutor sensor
    5.6 Electrochemical sensor
    5.7 Flame ionization detector (FID)
    5.8 Flame temperature analyser (FTA)
    5.9 Photo ionization detector (PID)
    5.10 Paramagnetic oxygen detector
6 Operation of fixed gas detection systems
    6.1 General
    6.2 Installation
    6.3 Criteria for the placement of sensors and
          sampling points
    6.4 Operation
7 Operation of portable and transportable gas detection
    apparatus
    7.1 General
    7.2 Operation
8 Training
    8.1 Operator training
    8.2 Maintenance training
Annex A (informative) Physical and chemical principles
of sensors
A.1 - Catalytic sensors (see 5.2)
A.2 - Thermal conductivity sensors (see 5.3)
A.3 - Infrared absorption sensors (see 5.4)
A.4 - Semiconductor sensors (see 5.5)
A.5 - Electrochemical sensor (see 5.6)
A.6 - Flame ionization detectors (FID) (see 5.7)
A.7 - Flame temperature analyser (FTA) (see 5.8)
A.8 - Photo ionization detector (PID) (see 5.9)
A.0 - Paramagnetic oxygen detector (see 5.10)
Annex B (informative) Nature of a release
B.1 - General
B.2 - Parameters influencing the release
B.3 - Outdoor sites and open structures
B.4 - Buildings and enclosures
Annex C (informative) Measuring ranges up to LEL
C.1 - Reference to the annex of EN 50054
Annex D (informative) Environmental parameters
D.1 - Typical environmental conditions used in type testing

Provides guidance on selecting, installing, use and maintenance of electrically operated Group II apparatus, to be used in industrial and commercial safety applications for detecting of combustible gases and oxygen.