Well, of course "without humidity" is not a practical condition for a storage room.

I guess this is an issue of translation. The original Japanese SDS translates to something closer to "Store indoors, away from water and humid places."

If you break down the individual phrases in the original Japanese you get:
"Don't get (it) wet"
"Don't put (it in a) high humidity place"

Still not quantifiable, but as long as the rod is sealed in an original, unopened can any reasonable storage space should be fine.

@MintJulep
Appriciated your reply.
Can you please advice me what high humidity value is? Because client request me mention the detail of temperature and humidity value in the procedure.

Sorry, I can't give you a number that would have any validity.

At any rate, LB-52U is a low-hydrogen electrode. So, it should be (must be?) baked (dried) before use anyway.

@MintJulep
Thank you so much for your advice.
Sure that LB-52U must be baked (dried) before using except the vacuum packed electrode.

Search for "storage and handling" info sheets from various consumable producers.
Commonly, storage < 60% relative humidity is recommended.

Ofcourse, low hydrogen rods (3.5 ml/100g) require different measures. If vacuum packaged, storage doesn't matter as long as the packs are not pierced.
If not, they should be dried right before use, or conditioned in an efficient way (e.g. redried at 300-350 °C for no longer than 3 hrs and held at 80°C until the moment they're used).

@kingnero
Thanks bro. I searched for LB-52U already. But I just got as posted photo.
For other manufacturer such as Hyundai, Lincoln, Oxford,...,they mentioned quite clear, but not Kobelco.