List of external influences

From Electrical Installation Guide

Figure E65 below is from IEC 60364-5-51, which should be referred to if further details are required.

Fig. E65 – List of external influences (taken from Appendix A of IEC 60364-5-51)
Code External influences Characteristics required for equipment
A - Environment
AA Ambient temperature (°C)
Low High
AA1 - 60 °C + 5 °C Specially designed equipment or appropriate arrangements
AA2 - 40 °C + 5 °C
AA3 - 25 °C + 5 °C
AA4 - 5° C + 40 °C Normal (special precautions in certain cases)
AA5 + 5 °C + 40 °C Normal
AA6 + 5 °C + 60 °C Specially designed equipment or appropriate arrangements
AA7 - 25 °C + 55 °C
AA8 - 50° C + 40 °C
AB Atmospheric humidity
Air temperature (°C) Relative humidity (%) Absolute humidity (g/m3)
Low High Low High Low High
AB1 - 60 °C + 5 °C 3 100 0.003 7 Appropriate arrangements shall be made
AB2 - 40 °C + 5 °C 10 100 0.1 7
AB3 - 25 °C + 5 °C 10 100 0.5 7
AB4 - 5° C + 40 °C 5 95 1 29 Normal
AB5 + 5 °C + 40 °C 5 85 1 25 Normal
AB6 + 5 °C + 60 °C 10 100 1 35 Appropriate arrangements shall be made
AB7 - 25 °C + 55 °C 10 100 0.5 29
AB8 - 50 °C + 40 15 100 0.04 36
AC Altitude
AC1 ≤ 2000 m Normal
AC2 > 2000 m May necessitate precaution (derating factors)
AD Presence of water
AD1 Negligible Probability of presence of water is negligible IPX0
AD2 Free falling drops Probability of presence of water is negligible IPX1 or IPX2
AD3 Sprays Possibility of water falling as a spray at an angle up to 60° from the vertical IPX3
AD4 Splashes Possibility of splashes from any direction IPX4
AD5 Jets Possibility of jets of water from any direction IPX5
AD6 Waves Possibility of water waves (seashore locations) IPX6
AD7 Immersion Possibility of intermittent partial or total covering by water IPX7
AD8 Submersion Equipment is permanently and totally covered IPX8
AE Presence of foreign solid bodies or dust
Smallest dimension Example
AE1 Negligible IP0X
AE2 Small objects 2.5 mm Tools IP3X
AE3 Very small objects 1 mm Wire IP4X
AE4 Light dust IP5X if dust penetration is not harmful to functioning
IP6X if dust should not penetrate
AE5 Moderate dust
AE6 Heavy dust IP6X
AF Presence of corrosive or polluting substances
AF1 Negligible Normal
AF2 Atmospheric According to the nature of the substance
AF3 Intermittent, accidental Protection against corrosion
AF4 Continuous Equipment specially designed
AG Mechanical shock
AG1 Low severity Normal, e.g. household and similar equipment
AG2 Medium severity Standard industrial equipment, where applicable, or reinforced protection
AG3 High severity Reinforced protection
AH Vibrations
AH1 Low severity Household or similar Normal
AH2 Medium severity Usual industrial conditions Specially designed equipment or special arrangements
AH3 High severity Severe industrial conditions
AK Presence of flora and/or moulds growth
AK1 No hazard Normal
AK2 Hazard Special protection
AL Presence of fauna
AL1 No hazard Normal
AL2 Hazard Special protection
AM Electromagnetic, electrostatic or ionising influences / Low frequency electromagnetic phenomena / Harmonics
AM1 Harmonics, interharmonics Refer to applicable IEC standards
AM2 Signalling voltage
AM3 Voltage amplitude variations
AM4 Voltage unbalance
AM5 Power frequency variations
AM6 Induced low-frequency voltages
AM7 Direct current in a.c. networks
AM8 Radiated magnetic fields
AM9 Electric field
AM21 Induced oscillatory voltages or currents
AM22 Conducted unidirectional transients of the nanosecond time scale
AM23 Conducted unidirectional transients of the microsecond to the millisecond time scale
AM24 Conducted oscillatory transients
AM25 Radiated high frequency phenomena
AM31 Electrostatic discharges
AM41 Ionisation
AN Solar radiation
AN1 Low Normal
AN2 Medium
AN3 High
AP Seismic effect
AP1 Negligible Normal
AP2 Low severity
AP3 Medium severity
AP4 High severity
AQ Lightning
AQ1 Negligible Normal
AQ2 Indirect exposure
AQ3 Direct exposure
AR Movement of air
AR1 Low Normal
AR2 Medium
AR3 High
AS Wind
AS1 Low Normal
AS2 Medium
AS3 High
B - Utilization
BA Capability of persons
BA1 Ordinary Normal
BA2 Children
BA3 Handicapped
BA4 Instructed
BA5 Skilled
BB Electrical resistance of human body (under consideration)
BC Contact of persons with earth potential
BC1 None Class of equipment according to IEC61140
BC2 Low
BC3 Frequent
BC4 Continuous
BD Condition of evacuation in case of emergency
BD1 Low density / easy exit Normal
BD2 Low density / difficult exit
BD3 High density / easy exit
BD4 High density / difficult exit
BE Nature of processed or stored materials
BE1 No significant risks Normal
BE2 Fire risks
BE3 Explosion risks
BE4 Contamination risks
C - Construction of building
CA Construction materials
CA1 Non combustible Normal
CA2 Combustible
CB Building design
CB1 Negligible risks Normal
CB2 Propagation of fire
CB3 Movement
CB4 Flexible or unstable