ONORM EN 1127-1 : 2011

Foreword
0 Introduction
1 Scope
2 Normative references
3 Definitions and abbreviations
4 Hazard identification
    4.1 General
    4.2 Combustion properties
    4.3 Ignition requirements
    4.4 Explosion behaviour
5 Elements of risk assessment
    5.1 General
    5.2 Determining the amount and likelihood of an
          occurrence of an explosive atmosphere
          5.2.1 Degree of dispersion of flammable substances
          5.2.2 Concentration of flammable substances
          5.2.3 Amount of explosive atmosphere
    5.3 Determining the presence of effective ignition
          sources
          5.3.1 General
          5.3.2 Hot surfaces
          5.3.3 Flames and hot gases (including hot particles)
          5.3.4 Mechanically generated sparks
          5.3.5 Electrical apparatus
          5.3.6 Stray electric currents, cathodic
                  corrosion protection
          5.3.7 Static electricity
          5.3.8 Lightning
          5.3.9 Radio frequency (RF) electromagnetic
                  wave
          5.3.10 Electromagnetic waves
          5.3.11 Ionizing radiation
          5.3.12 Ultrasonics
          5.3.13 Adiabatic compression and shock waves
          5.3.14 Exothermic reactions, including self-ignition
                  of dusts
    5.4 Estimating the possible effects of an explosion
6 Elimination or minimisation of risk
    6.1 Fundamental principles
    6.2 Avoidance or reduction of the amount of explosive
          atmosphere
          6.2.1 General
          6.2.2 Process parameters
          6.2.3 Design and construction of equipment,
                  protective systems and components
    6.3 Classification of hazardous places
          6.3.1 General
          6.3.2 Zones for gases/vapours
          6.3.3 Zones for dusts
    6.4 Requirements for the design and construction
          of equipment, protective systems and components
          by avoidance of effective ignition sources
          6.4.1 General
          6.4.2 Hot surfaces
          6.4.3 Flames and hot gases
          6.4.4 Mechanically generated sparks
          6.4.5 Electrical apparatus
          6.4.6 Stray electric currents and cathodic
                  corrosion protection
          6.4.7 Static electricity
          6.4.8 Lightning
          6.4.9 Radio frequency (RF) electromagnetic
                  waves
          6.4.10 Electromagnetic waves
          6.4.11 Ionizing radiation
          6.4.12 Ultrasonics
          6.4.13 Adiabatic compression and shock waves
          6.4.14 Exothermic reactions, including
                  self-ignition of dusts
    6.5 Requirements for the design and construction of
          equipment, protective systems and components to
          reduce the explosion effects
          6.5.1 General
          6.5.2 Explosion-resistant design
          6.5.3 Explosion relief
          6.5.4 Explosion suppression
          6.5.5 Prevention of explosion propagation
                  (explosion decoupling)
    6.6 Provisions for emergency measures
    6.7 Principles of measuring and control systems for
          explosion prevention and protection
7 Information for use
    7.1 General
    7.2 Information on equipment, protective systems and
          components
    7.3 Information for commissioning, maintenance and
          repair to prevent explosion
    7.4 Qualifications and training
Annexes
A (normative) Tools for use in potentially explosive
atmospheres
B (normative) Relationship between categories and zones
C (informative) Concepts for the use of measuring and
control systems to avoid effective ignition sources
D (informative) Index
ZA (informative) Clauses of the European Standard
addressing essential requirements or other provisions
of EU Directives

Defines procedures for identifying and assessing hazardous situations leading to explosion and the design and construction measures required for safety.