^ Off-topic much
The problem isn't so much sleeping during the day: there are several benefits for taking naps and in many cultures is actually something pretty common. The problem is like you very well pointed, not going to bed/waking up at the same time, as this can disrupt your circadian cycle and influence the quality of your sleep.
As someone who does shifts (yesterday I got up at 5am, today I'm working till 1am, tomorrow till 4am), it's more important to find a balance in the middle of the chaos. Study your work hours and see how can you fit the biggest amount of sleep in the most consistent way possible: it's better to loose 1/2 hours of sleep if it means you're waking up at a closer hour than the rest of the week. At the same time, don't sleep in, but instead go to bed earlier when you want to compensate for lack of sleep. The most important thing is sleep quality, not quantity (I believe there's one study that shows that 8 hours of sleep with constant awakenings end up being as harmful as 4 hours of sleep).
If you have no troubles falling/continuing sleeping, it doesn't harm you. Much more important are things like the room-temperature, light exposure, etc. In fact, the fan might actually increase your sleep quality by silencing those noises (I have the same problem due neighbors

).
PS: another study (wil link it later), shows that the way YOU FEEL about the amount of sleep you get also matters (placebo ofc): when you sleep few hours, don't think "no dreams, no recall, blaah!" but instead "yay, more rem next night!"
Just realized I'm late for work yay

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