NaBH4, sodium borohydride, CAS 16940-66-2
Safety: R14/15, R34, R24/25
Handling and storage
Handling: Avoid contact with skin, eyes and clothing. Wear suitable protective equipment. Avoid contact with water. Do not breathe vapours or spray mist. Wash thoroughly after handling. Ensure adequate ventilation. Keep container tighly closed.
Storage
Storage conditions: Keep containers tightly closed in a dry, cool and well-ventilated place. Keep away from heat and sources of ignition. Do not store this material in containers made of the following: glass, aluminium.
Storage temperature: < 60°C
Further information: Sodium borohydride can liberate flammable hydrogen gas upon contact with acids, oxidizing agents, water and transition metal salts. Moisture can cause the product to decompose and slowly liberate hydrogen, which can accumulate in the headspace of the storage container. Drums should be ventilated by loosening the top bung prior to opening.
Why not glass? I'm not sure, but maybe it is related to the fact that glass contains several metal ions, which might react with the borohydride. Just a guess though.