* 분사 = 1) spray of fine liquid particles (분사하다 = to spray), 2) participle (as in English grammar).
* 장 = 1) head of an organization, 2) place, venue, 3) sheet (of paper, etc.), 4) chapter, (and there's more).
장 is very common, but 분사장 doesn't seem to be a word. I've never heard it and it's not in the dictionary.
The only thing I can think of is referring to a chapter in a grammar book talking about participles. For example, 동사장 would be the "verb" chapter, and 분사장 the "participle" chapter. This is not a very common usage, but you could say it.