I.S. EN 61241-1:2004

FOREWORD
INTRODUCTION
1 Scope
2 Normative references
3 Terms and definitions
4 Construction
5 Practice A and practice B
6 Supplementary requirements for electrical apparatus protected
  by enclosures for practice A for use in zones 20, 21 and 22
7 Supplementary requirements for electrical apparatus protected
  by enclosures for practice B for use in zone 20 or 21
  7.1 Joints
      7.1.1 Plain joints
      7.1.2 Spigotted joints
      7.1.3 Gasketed joints
  7.2 Operating rods, spindles or shafts
      7.2.1 General
      7.2.2 Running contact seals
      7.2.3 Power shafts
      7.2.4 Operating rods
  7.3 Clearance of bolts
8 Verification and tests
  8.1 General
  8.2 Type tests
      8.2.1 Tests for dust exclusion by enclosures
      8.2.2 Thermal tests
9 Marking
Bibliography
Figures
Tables

Applies to electrical apparatus protected by enclosures and surface temperature limitation for use in areas where combustible dust may be present in quantities which could lead to a fire or explosion hazard. Specifies requirements for design, construction and testing of electrical apparatus. The ignition protection is based on the limitation of the maximum surface temperature of the enclosure and on other surfaces which could be in contact with dust and on the restriction of dust ingress into the enclosure by the use of 'dust-tight' or 'dust-protected' enclosures.