Page 18 - Electrical Installation in Hazardous Area

Contents xv

19.9 Pressurized enclosures in dust risks 557
19.10 Analyser houses 558
19.10.1 Pressurization considerations 559
19.10.2 Analyser house construction and protection 563
19.11 Pressurized rooms 563

20 Installation of intrinsically safe apparatudassociated
apparatus and intrinsically safe systems 'i' 566
20.1 Standards and Codes 567
20.2 Basic installation requirements 568
20.3 Cables, conduits and conductors 569
20.3.1 Conductor temperature 569
20.3.2 Inductance and capacitance 570
20.3.3 Cable installation 571
20.3.4 Conduit installation 572
20.3.5 Marking of cables, cable bundles, cable trays,
or ducts and conduits 572
20.3.6 Additional requirements for Zone 0 (and
Zone 20 where appropriate) 573
20.4 Conductor terminations 573
20.4.1 Terminal construction 574
20.4.2 Assemblies of terminals 577
20.5 Earthing and bonding 581
20.5.1 Typical Zone 1 and Zone 21 intrinsically safe
circuits with bonding in the non-hazardous
area 584
20.5.2 Typical Zone 1 and Zone 21 intrinsically safe
circuits with bonding in the hazardous area 587
20.5.3 Typical Zone 1 and Zone 21 circuits with
bonding connection at more than one point 587
20.5.4 Bonding and insulation of screens for
intrinsically safe circuits 589
20.5.5 Typical Zone 0 and Zone 20 intrinsically safe
circuits 59 1
20.5.6 Special circuits 595

21 Documentation, inspection, test and maintenance of 598
explosion protected apparatus, systems and installations
21.1 Documentation 598
21.2 Detailed inspection requirements 599
21.2.1 Initial inspection 599
21.2.2 Inspection after apparatus repair 604
21.2.3 Inspection after change in area classification,
sub-group or surface temperature classification 604
21.2.4 Routine inspection 604