-=-Dead Space-=-
High orbit
Part 6
After briefly considering hijacking an astropath to search for local warp anomalies, you decide to first check for more mundane disturbances. Air circulation is a vital part of shipboard life, and one of the most common sources of discomfort for passengers, along with lighting and noise. It's entirely possible that the evaluation by the shipboard crew overlooked some subtle fault, through laziness or incompetence.
Perhaps an outsider with loyalty to the Guard would do better? To that end you vox in a request to the mechanised company, and after some confusion you get the services of an enginseer initiate. Not the most prestigious of roles, but the lower orders of the Cult Mechanicus tend to be relentlessly practical and competent in the pursuit of their duties. However, that's as far as they can get unless they begin pondering the deeper mysteries of the Truth and the Omnissiah and other such mystical and non-work related subjects.
This one is exactly as unimaginative and sensible as you could hope. From what you can see he has only some basic implants to assist his work, nothing flashy or impractical. After a brief greeting and a critical glance around the bunkhouse, he immediately begins waving a device around and manipulating the controls on a portable console. What little emotion displayed seems to be that of vague annoyance, though you can't tell if it's at you for calling him on an errand, or at the problem that eludes resolution.
After a few minutes of divining, the initiate gives you a report; no exotic or dangerous chemicals, no atmospheric imbalances, nothing dangerous or out of the ordinary. You mention that the ventilation seems to be the only plausible cause, and he gives a near-human shrug before leading you to the main air duct.
The vent is large enough for a person to crawl through, but is completely covered by an opaque filtration grill. The initiate points out the sanctified seal, the sign of any proper Imperial maintenance and one of the few consistent elements of competence he's seen aboard. Approvingly, he notes the entries on the attached log; it shows that it was accessed and sealed twice in the last few days with all proper rituals observed.