NS EN 13821 : 1ED 2003

Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 Test apparatus
  4.1 Spark generation circuit
  4.2 Test vessel
5 Test sample
6 Test procedure
  6.1 Test description
  6.2 Calibration
  6.3 Conformity
      6.3.1 Conformity tests
      6.3.2 Criteria for conformity
  6.4 Test report
Annex A (normative) Descriptions of spark generating systems
      A.1 General
      A.2 Triggering by high-voltage relay, using a
          two-electrode system
      A.3 Triggering by electrode movement, using a
          two-electrode system
      A.4 Triggering by auxiliary spark, using 3-electrode
          system
      A.5 Triggering by voltage increase, using two-electrode
          system
      A.6 Triggering by transformer, using two-electrode
          system
      A.7 Example of a test apparatus
Annex ZA (informative) Clauses of this European Standard
         addressing essential requirements or other provisions
         of EU Directives
Bibliography

Specifies a method of test to be determine the minimum ignition energy of a dust/air mixture by an electrically-generated spark.