I.S. EN 50381:2004

1 Scope
2 Normative references
3 Definitions
4 Construction requirements for TVR's and ducting
   4.1 General
   4.2 Degree of ingress protection
   4.3 Design and construction
   4.4 Mechanical strength
   4.5 Penetrations
   4.6 Floor drains
   4.7 Floors
   4.8 Doors
   4.9 Inspection window(s)
   4.10 Apertures
   4.11 Enclosures
5 Requirements for TVR's, equipment group I, type of
   protection vM2
6 Ventilation requirements for TVR's, equipment group II
7 Additional ventilation requirements for TVR'S with an
   internal source of release
8 Temperature limits
9 Minimum safety provisions and devices
10 Additional safety provisions and devices for TVR's
   meeting the requirements of type of protection v2 and
   vM2
11 Additional requirements for TVR's with an internal
   source of release
   11.1 Assessment of containment systems
   11.2 Release conditions
        11.2.1 No release
        11.2.2 Release of a flammable liquid
   11.3 Design requirements for the containment system
        11.3.1 Infallible parts of the containment system
        11.3.2 Containment system with limited release
   11.4 Ignition capable apparatus in the case of type of
        protection v2
   11.5 Location of apparatus in the case of type of protection
        v3
   11.6 Internal hot surfaces
        11.6.1 Loss of minimum pressure differential, type of
               protection v2
        11.6.2 Loss of ventilation flow, type of protection v2
        11.6.3 Loss of ventilation flow, type of protection v3
   11.7 Potential source of internal release
12 Requirements for gas detectors
13 Supply of protective gas
   13.1 Ventilation
   13.2 Leakage Compensation of a Breathable Atmosphere (LCBA)
   13.3 Density limits
14 Type verification and tests
   14.1 Sequence of tests
   14.2 Thermal tests
   14.3 Overpressure test
   14.4 Purging test
   14.5 Verification of minimum pressure differential
   14.6 Ventilation flow rate tests for TVR's with an internal
        source of release
   14.7 Overpressure test for containment systems with limited
        release
   14.8 Verification of sequence of operation of the safety
        devices
   14.9 Additional tests
15 Routine tests
   15.1 Test conditions
   15.2 Verification of minimum pressure differential
   15.3 Ventilation flow rate tests for TVR's with an internal
        source of release
   15.4 Overpressure test for containment systems with limited
        release
   15.5 Verification of sequence of operation of the safety
        devices
   15.6 Additional tests
16 Marking
   16.1 TVR's all cases
   16.2 TVR's with a containment system
   16.3 Safety related control systems
   16.4 Additional marking
17 Instructions
Annex A (normative) Method of protection of electrical
        apparatus containing a potential release of a
        flammable gas or vapour
   A.1 Introduction
   A.2 Definitions
   A.3 Requirements
Annex B (normative) Method of protection of electrical
        apparatus containing a potential release of a
        flammable liquid
   B.1 Introduction
   B.2 Definitions
   B.3 Requirements
   B.4 Flammable non-flashing liquids
   B.5 Spark and particle barriers
   B.6 Flashing liquids
Annex C (informative) Determination of peak rise in
        enclosure pressure, resulting from an internal
        release of a flashing liquid
   C.1 Introduction
   C.2 Definitions
Annex D (informative) Method of protection of electrical
        apparatus containing a potential release of a
        flammable gas or vapour
Annex E (informative) Mathematical model of dilution of a
        source of release
Bibliography