English to Italian Tech/Engineering Manufacturing

STORAGE
Vapour samples cannot be stored. Liquid Gas samples can be stored; with the exception of ethylene which cannot be stored as the time between sampling and analysis is a maximum 5 hours. Butadiene must be stored in an explosion-proof refrigerator between -5°C and 5°C.
CLEANING AND MAINTENANCE
The cleaning procedure is applicable to flammable liquefied gases such as propanes, butanes, pentanes, etc. All flammable gas cylinders must be flared in a hood.
Examine the sample cylinder to be sure it is in good working order and contains a rupture disc. Determine which side the “dip tube” is on and the general condition of the cylinder.