Foreword
1 Scope
2 Normative references
3 Terms and definitions and symbols
   3.1 General terminology
   3.2 Functional variables
   3.3 Operating features
   3.4 Further design terminology
4 Construction requirements
   4.1 Basic requirements
   4.2 Materials
   4.3 Strength of housings
5 Functional requirements
   5.1 General
   5.2 Shell strength, external tightness and internal
        sealing
   5.3 Accuracy group
   5.4 Response time
   5.5 Relatching difference and unlatching
   5.6 Closing force
   5.7 Endurance and accelerated ageing
   5.8 Resistance to gas of plastic components
   5.9 Maximum flow with respect to the performances of
        the trip mechanism and the valve seat
   5.10 Flow coefficient
   5.11 Final inspection
6 Testing
   6.1 Types of tests
   6.2 Selection of test samples
7 Test methods
   7.1 General
   7.2 Shell strength, external tightness and internal
        sealing
   7.3 Accuracy group
   7.4 Response time
   7.5 Relatching difference and unlatching
   7.6 Closing force
   7.7 Endurance and accelerated ageing
   7.8 Resistance to gas of plastic components
   7.9 Verification of the strength of the trip
        mechanism, valve seat and closing member
   7.10 Determination of flow coefficient
   7.11 Final inspection
8 Documentation
   8.1 Documentation related to type test
   8.2 Documentation for the customer
   8.3 Documentation related to surveillance
9 Marking
   9.1 Mandatory markings
   9.2 Marking of connecting nipples for sensing,
        exhaust and breather lines
   9.3 Identification of auxiliary devices
Annex A (informative) Use of allowable pressure p[zul]
Annex B (informative) Ice formation
   B.1 General
   B.2 Requirements
   B.3 Tests
Annex C (informative) Conformity evaluation
   C.1 General
   C.2 Manufacturer's conformity evaluation
   C.3 Third parties' conformity evaluation
   C.4 Issue of the certificate of conformity
Annex D (informative) Pressure drop and flow coefficient
   D.1 Calculation method for pressure drop throughout
        the safety shut-off device
   D.2 Test method for the determination of the flow
        coefficient C[v]
Annex E (informative) Alternative test method to verify
        the maximum flow with respect to the performance
        of trip mechanism
   E.1 Test method
   E.2 Test method for the determination of the dynamic
        factor C[r]
   E.3 Test method for a series of safety shut-off
        devices
Annex F (informative) Sizing equation
Annex G (informative) Inspection certificate
Annex H (informative) Order specification
   H.1 Minimum specifications
   H.2 Optional specifications
Annex I (informative) Acceptance test
Bibliography