Ex Equipment Code Application

"Whatever method of protection is used, there are always limitations on the

level of protection offered in environmental terms. Any exceptional

circumstance will not necessarily be covered by the certification, and

engineering judgement has to be exercised. Some of the factors to be

considered are:

Temperation - either extreme

Exposure to water - incl. condensation

Vibration and impact

Corrosion

Chemical activity - particularly affecting choice of cable

Exposure to ultra-violet rays or other radiation

Intrinsic safety is in general less influenced than other techniques by these factors, but

their extremes could result in certification not being valid, and occasionally an installation

could become dangerous. In comparison, it is quite obvious that a flameproof

enclosure half full of rusty water being electrolyzed to hydrogen and oxygen is not safe.

In practice, there is not often a major problem, but blind faith in certification can lead to

difficulties."

your training will have already shown you that you can use either of those in zones 1 and 2. It should also have made you aware that there is no such thing as an ex I junction box!

Did you sue the training provider, Mildred?

Which standards are you thinking of, or do you mean Ex ia/ib under European ATEX and IECEx standards?

Yes for a junction box Ex e is fine and common under European ATEX rules as long as the junction box and terminals are Ex e ATEX certified.

Site preferences, consultants, environment, etc however may dictate the use of one protection method over the other regardless of if both comply, so you may need to check.

Be careful, mentioning "Site preferences, consultants, environment, etc however may dictate the use of one protection method over the other regardless of if both comply, so you may need to check." may get you an OT. Like the one I got from some B-hole.

Ex d may often be applied to methane, but is very limited for hydrogen. Ex i is widely applicable but restricted to low power. A method of protection is not applicable to any risk.