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Technical Information

Types of explosive gases applied to explosion-proof devices

When selecting an explosion-proof device, it is important to carefully review the device's explosion-proof structure type, temperature characteristics, and type of gas and steam used. The table below introduces the temperature characteristics according to the type and grade of explosive gas and steam specified by the IEC (International Electrotechnical Commission) and KS (Korea Industrial Standards Association). Please refer to this when selecting a product.

IEC regulations

Class of protective structureTypes of Gases and Steam
IMethane (firedamp)
IIA
Ammonia
Ethyl methyl ketone
Carbon Monoxide
n-propyl acetate
Pentane
Chlorethylene
ISO octane
Isobutanol
Xylene
Acetone
Blast furnace gas
Ethyl acetate
Butane
Amyl acetate
Heptane
Ethanol
Benzene
Industrial methane
Methyl acetate
Propane
n-butyl acetate
Hexane
Methanol
Decane
Amyl alcohol
Cyclohexane
IIB
Buta-1,3-diene
Ethylene oxide
Ethylene
Town gas
Diethyl ether
IICHydrogen
temperature characteristicsRatingT1T2T3T4T5T6
maximum surface temperature450°C300°C200°C135°C100°C85°C

KS (JIS) regulations

Flammability
/
explosion rating		range of flash point
Above 450°CAbove 300°C but below 450°CAbove 200°C but below 300°CAbove 135°C but below 200°CAbove 100°C but below 135°CAbove 85°C but below 100°C
G1G2G3G4G5G6
I
Acetic acid
Acetone
Ammonia
Benzene
Carbon
Athyl acetate
Monoxide
Acetic anhydride
Amyl
Acetate-iso
Butane
1-butanol
Ethanol
Gasoline
heptane
hexane
Octanes
Ethyl mercaptan
n-butyladehyde
Terahydrofuran
Crotonaidehyde
Isoprene
1-pentanol
Acetaldehyde
Methyl eher
 Ethylnitrite
IIA Coal gas
Ethylene
Ethylene oxide
 Hydrogen sulfide
Hydrogen
Water gas
 Ethyl Limit of nitrate
IIB
IIC		a
b
Carbon
Disulphide
cAcethelene

Types of explosion-proof structures

Pressure-resistant explosion-proof structured
Hydraulic explosion-proof structureo
Pressure-resistant explosion-proof structuref
Increased safety explosion-proof structuree
Intrinsically safe explosion-proof structurei
Special explosion-proof structures

Example of symbol application

dIndicates that the overall protective structure of the equipment is manufactured as a pressure-resistant explosion-proof structure.
2Indicates that it can be applied and used for gases and vapors corresponding to triggering grades 1 and 2.
G4Indicates that it can be applied and used for gases and vapors corresponding to ignition degrees G1, G2, G3, and G4.

Waterproof-dustproof protection structure

IEC regulations (IEC529)

IP -
Protection level against human body and solid foreign substances
Degree of protection against water ingress

※ IP: Protection characteristic symbol International Protection

Protection level against human body and solid foreign substances

Ratingdegree of protectionRatingdegree of protection
0No special protection4The ends of solid objects, such as wires or steel strips, exceeding 1 mm in diameter or thickness should not enter the interior.
OneThe ends of solid objects such as wires or steel strips exceeding 50 mm in diameter or thickness should not enter the interior.5Dust larger than enough to affect operation does not enter the interior.
2The ends of solid objects such as wires or steel strips exceeding 12 mm in diameter or thickness should not enter the interior.6Dust does not enter the interior.
3The ends of solid objects such as wires or steel strips exceeding 2.5 mm in diameter or thickness should not enter the interior.

Degree of protection against water ingress

Grade
(KS designation)		degree of protectionTest Methods
0
(-)		No special protectionNo special protection against water ingressno exam
1
(spinning type)		Protection against falling waterNo harmful effects from vertically falling waterSpray water from the test device on the right for 10 minutes.
2
(spinning type)		Protection against falling waterNo harmful effects from falling water within 15° from the vertical.Spray water for 10 minutes in a 15° vertical direction from the test device on the right.
3
(rainproof)		protection against rainfallNo harmful effects from rainfall within 60° of the vertical.Spray water from the test device on the right in a vertical direction of 60° for 10 minutes.
4
(splash proof)		protection against dropletsNo harmful effects from water splashes from all directionsSpray water from the test device on the right in all directions for 15 minutes.
5
(room classification type)		Protection of classified waterNo harmful effects from direct jetting of water in any direction.Spray water from the test device on the right in all directions for 15 minutes.
6
(domestic type)		protection against blueNo harmful effects from direct jets of water in all directionsSpray water from the test device on the right in all directions for 15 minutes.
7
(Policy type)		Protection against submersionWater does not enter even if submerged in water for a specified period of time.Place in 1m of water for 30 minutes.

※ In general, the following configuration is mainly used, and any other configuration is considered unreasonable.
IP00/IP11, IP12/IP21, IP22, IP23/IP31, IP33, IP34/IP41, IP42, IP43, IP44/IP54, IP55, IP56/IP65, IP66, IP67, IP68