Per 
Item #: SCP-4193
Object Class: Keter
Special Containment Procedures: SCP-4193 is currently located within a desert in █████, ████. Due to SCP-4193's mostly unknown properties, Class-D personnel are currently allowed to enter for testing. Any unusual patterns from SCP-4193-1 are to be reported to the personnel responsible for Site-███
Description: SCP-4193 is a high school building located in █████, ████. From the outside its appearance does not appear unusual. However, when a human enters and is at least 17-39 meters from the exit, SCP-4193's anomalous properties will take effect. The human who has entered will be surrounded by an unknown solid. They will then proceed to suffocate to death, whereafter the solid will disappear. SCP-4193-1 has been observed ringing after the subject's death.
SCP-4193-1 is a bell located in a tower above the facility. It has only been observed to play when a subject has expired. Due to SCP-4193's nature, nobody has entered the tower containing the bell as of yet. A second bell is located in a tower on the exact opposite side of SCP-4193-1. The second bell however (previously known as SCP-4193-2), has not shown any anomalous properties as of now.
Addendum: Incident 4193-AA
On ██/██/████ , Agent ████████ entered SCP-4193. She walked about 17 meters before screeching over the radio. Personnel that were present during the incident report seeing a brown-ish material instead of the school halls that were usually seen. Agent ████████ claims to have been surrounded by this material, which apparently was a solid. She claims that it had become harder to breathe. ██ hours after initially entering Agent ████████ had deceased due to air becoming thin. She had suffocated.
[BEGIN LOG]
Agent ████████: I'm entering the facility.
Dr ██████: Mhm, just don't go too far. We don't know what this thing can do. Yet.
Agent ████████: Alright Doc.
( Personnel currently connected to frequency 45.8 have reported hearing a screech. Assumed to originate from Agent ████████ )
Dr ██████: What in the world is that thing?!
Agent ████████: I don't know, I think I'm inside of it.
Dr ██████: It looks liquid, is it?
Agent ████████: It's a solid. Definitely.
Agent █████: Doc, we are unable to get in. I don't think she will get out.
Dr ██████: Alright, calm down. ████████, can you answer some questions?
Agent ████████: Alright then.
Dr ██████: What do you think the solid is.
Agent ████████: Nothing. Absolutely nothing.
Dr ██████: What do you mean «nothing»?
Agent ████████: It's nothing. I mean, it's the solid state of nothing. I can't tell you anything else.
Dr ██████: Very well. Report if anything happens.
Agent ████████: Roger that, Doc.
( ██ hours after entering, one of the two bells rings. Almost in the same exact moment the solid disappears. Agent ████████ was declared MIA following this incident. )
[END LOG]
