Fair enough no probs here.
Must admit when trying to explain stuff to Korean/foreign clients I shouldn't complain when they can't grasp what I'm telling them.
I mean.........explaining the difference between EXd and EXe to a Korean in a broad Geordie accent lol.
Poor guy has no chance :confused5:
I'm pretty sure the Koreans will be using the Americain NFPA 70 (NEC Code) etc, which categorize hazardous areas into Class/Divisions/Groups, and can be quite different to the European Ex system, as in what measures of protection etc is required. Not sure if you have worked to the Yank system or not, but have included a rough guide as to how such areas would be categorized...
North American hazardous locations classification in classes, divisions and groups
In general hazardous locations in North America are separated by classes, divisions, and groups to define the level of safety required for equipment installed in these locations.
Classes
The classes defines the general nature of hazardous material in the surrounding atmosphere.
Class
| Hazardous Material in Surrounding Atmosphere
|
Class I
| Hazardous because flammable gases or vapors are present in the air in quantities sufficient to produce explosive or ignitable mixtures.
|
Class II
| Hazardous because combustible or conductive dusts are present.
|
Class III
| Hazardous because ignitable fibers or flyings are present, but not likely to be in suspension in sufficient quantities to produce ignitable mixtures. Typical wood chips, cotton, flax and nylon. Group classifications are not applied to this class.
|
Divisions
The division defines the
probability of hazardous material being present in an ignitable concentration in the surrounding atmosphere.
Division
| Presence of Hazardous Material
|
Division 1
| The substance referred to by class is present during normal conditions.
|
Division 2
| The substance referred to by class is present only in abnormal conditions, such as a container failure or system breakdown.
|
Groups
The group defines the hazardous material in the surrounding atmosphere.
Group
| Hazardous Material in Surrounding Atmosphere.
|
Group A
| Acetylene
|
Group B
| Hydrogen, fuel and combustible process gases containing more than 30% hydrogen by volume or gases of equivalent hazard such as butadiene, ethylene, oxide, propylene oxide and acrolein.
|
Group C
| Carbon monoxide, ether, hydrogen sulfide, morpholine, cyclopropane, ethyl and ethylene or gases of equivalent hazard.
|
Group D
| Gasoline, acetone, ammonia, benzene, butane, cyclopropane, ethanol, hexane, methanol, methane, vinyl chloride, natural gas, naphtha, propane or gases of equivalent hazard.
|
Group E
| Combustible metal dusts, including aluminum, magnesium and their commercial alloys or other combustible dusts whose particle size, abrasiveness and conductivity present similar hazards in connection with electrical equipment.
|
Group F
| Carbonaceous dusts, carbon black, coal black, charcoal, coal or coke dusts that have more than 8% total entrapped volatiles or dusts that have been sensitized by other material so they present an explosion hazard.
|
Group G
| Flour dust, grain dust, flour, starch, sugar, wood, plastic and chemicals.
|
The specific hazardous materials within each group and their automatic ignition temperatures can be found in Article 500 of the National Electric Code and NFPA 497/ NFPA 70E.
Group A, B, C and D apply to class I locations. Group E, F and G apply to class II locations.
Temperature Code
A mixture of hazardous gases and air may ignite in contact with a hot surface. The condition for ignition depends on several factors as surface area, temperature and concentration of gas.
Equipment approved, receives a temperature code indicating the maximum surface temperature of the equipment.
Temperature Code
| Maximum Surface Temperature
| |
[SUP]o[/SUP]F
| [SUP]o[/SUP]C
| |
T1
| 842
| 450
|
T2
| 572
| 300
|
T2A
| 536
| 280
|
T2B
| 500
| 260
|
T2C
| 446
| 230
|
T2D
| 419
| 215
|
T3
| 392
| 200
|
T3A
| 356
| 180
|
T3B
| 329
| 165
|
T3C
| 320
| 160
|
T4
| 275
| 135
|
T4A
| 248
| 120
|
T5
| 212
| 100
|
T6
| 185
| 85
|
Equipment that does not exceed a maximum surface temperature of
212 [SUP]o[/SUP]F (
104 [SUP]o[/SUP]F ambient temperature) is not required to be marked with a temperature code (NEC).