Okay, here we go. I'll comment on the first 5-10ish specific nitpicks I have, then move on to an overall response based on how I'd react if I saw this posted to the mainsite. Here are my thoughts:
- Scp-4045 is currently situated at site-█ located ████████████. > try to avoid censoring anything in the containment, since it's the basic information that all personnel keeping the thing locked up should know. Also, Site-XX. Site numbers pretty much always have two to three digits.
- Remember to capitalize all letters in the SCP-XXXX designation.
- contained in a specialized humanoid chamber with direct access through a basic blast door to a room around the size of a tennis court, > this is overly complicated wording and the sentence is a run-on. Also, just give dimensions rather than making vague comparisons that most people don't automatically know. And you can state that there is an antechamber used for testing or the like.
- The chamber is fitted with one way windows and the room has a viewing compartment placed above the blast doors > why? Wouldn't it make more sense to just put a bunch of cameras in?
- Scp-4045 is restricted > I think you mean "access to SCP-XXXX's containment"
- to level 3+ personnel. > Level-3 or higher personnel
- All associated with Scp-4045 is > all what? And if "all" is plural, the verb should be "are".
- to wear full face masks to prevent all chances of Scp-4045 > You don't need to overexplain your containment procedures; stick to giving the instructions. The description content should provide answers regarding why those procedures are necessary.
- from ███████. > this sort of censorship is basically useless in-universe because there's not enough context to figure out what's here. And if it's part of the containment, that makes it even more problematic. Seven letters can be anything from "dragons" to "barfing".
Overall, this is a fairly typical monster manual humanoid, which we see variations of deleted from the mainsite a couple times a month. It has a lot of overcomplicated containment that seems to cause more trouble than it solves (I recommend reading this guide on containment to get a feel for how to write more logical, resource-conserving procedures) and everything is worded in a sort of overly convoluted manner rather than straightforward clinical tone.
Before progressing further with your writing, I suggest reading over this essay on common SCP pitfalls to get an idea of what elements to avoid putting in an SCP article, as well as the the humanoid writing guide if you haven't yet.
Definitely get the base idea polished up in the Ideas and Brainstorming forum before you try fixing the draft. There is no way this will do well as it currently is.