BS 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
Annex ZZ (informative) Coverage of Essential Requirements of
         EC Directives
Bibliography

Presents the specific requirements for the construction and testing of transportable ventilated rooms (TVR's), such as skid mounted analyser houses with type of protection 'v' intended for use in potentially explosive atmospheres.

1.1 This European Standard contains the specific requirements for the construction and testing of transportable ventilated rooms (TVR\'s), such as skid mounted analyser houses with type of protection \'v\' intended for use in potentially explosive atmospheres. Transportable in this sense means manufactured in one location (the manufacturer\'s premises) for trade and transportation to another location (the user\'s premises) for installation and use. This European Standard supplements European Standard EN 50014 or where appropriate EN 50021, the requirements of which apply to electrical apparatus with type of protection \'v\' except as modified within this standard. This standard does not contain the requirements for equipment group II, category 1 or equipment group I, category M1. This standard does not contain the requirements for equipment group I, category M2 where there exists a potential source of release. This standard does not contain the requirements for group II where there exists a potential hazard from combustible dusts. NOTE It is not the intention of this European Standard to cover stationary analyzer houses according to EN 61285. 1.2 This European Standard includes the requirements for the construction of the TVR and its associated components including, the inlet and outlet apertures for the ventilation gas supply and for the safety provisions and devices necessary for the type of protection \'v\'. 1.3 This European Standard specifies the requirements for TVR\'s with or without an internal source of release of potentially flammable or toxic, gas, liquid or vapour (for example analyzers placed within the TVR). 1.4 Due to the safety factors incorporated in the type of protection, the uncertainty of measurement inherent in good quality, regularly calibrated measurement equipment is considered to have no significant detrimental effect and need not be taken into account when making the measurements necessary to verify compliance of the apparatus with the requirements of this standard.