Is it permissible for the specialized worker to bring up the gas cylinder to the house when I am not present, given that there is another sister with my wife in the house?

Scholars have agreed on the prohibition of khalwa (private seclusion) with a non-mahram woman, based on the Prophet's (peace be upon him) saying: "No man should seclude himself with a woman unless a mahram is with her." It is permissible for a woman to allow a non-mahram man into her husband's house during his absence under two conditions: the husband's permission, and the absence of khalwa (i.e., with the presence of a mahram or another trustworthy woman). The fundamental and more cautious approach is that a man should not permit a non-mahram to enter his house unless a mahram is present.