Per 
Item #: SCP-XXXX
Class: Safe
Above: image of SCP-XXXX captured during early decompression phase upon entry into the structure (zone Alpha, two [2] units)
Containment procedure:
The airlock portion is to be kept in a pressure-sealed containment cell, fitted with a Pressure Warning System (PWS). Entry into SCP-XXXX is validated by Category 4 personnel only. Movement within the installation is currently limited to the beginning of Zone Theta (under direction of the O-5 Council). No electronic equipment is to be introduced into the airlock section of SCP-XXXX-A without approval from Category 4 personnel.
Description:
SCP-XXXX-A is a traversable art installation consisting of interconnected plastic vinyl chambers. The only externally visible part of the installation is a 4x4m tent-like structure, (designated as SCP-XXXX-AX) which serves as an airlock entry to the rest of the installation. The installation is comprised of an indeterminate number of these interconnected chambers. For information about the composition of SCP-XXXX, see the zoning table.
SCP-XXXX-B are instances of a United Electric VC-02 air pump(s) that provide a positive air pressure within the structure of SCP-XXXX-A, supporting the structure. The air pumps are entirely self-sustaining and do not require external power to operate; they are intermittently scattered within SCP-XXXX-A and thus far it has not been possible to remove them from the structure without triggering a decompression scenario.
SCP-XXXX-C is [DATA EXPUNGED].
The chambers within SCP-XXXX are multiple-sided curved polygons, ranging from a minimum side count of 4, up to a maximum observed side count of ████. The chambers either link together through archways, longer tunnels, or via [DATA REDACTED] within Zone Eta. The chambers maintain their structural integrity via an unknown number of SCP-XXXX-B, generating a positive air pressure of eight [8] atmospheres. When n is the number of sides of the chamber, the number of air pumps appears to be n-3. It must be noted that this formula only applies to zones Alpha to Gamma (see zoning table), and that the number of air pumps becomes inconsistent after moving past these zones. Investigations suggest that the chambers extend at least ████ units away from the central airlock, but this is not conclusive.
In order to enter, a manual zip is used in the entrance chamber, and functions as an airlock to maintain the structural integrity of the installation. If the airlock is left open and the air pressure drops below 1.7 atmospheres, instances of SCP-XXXX-B will attempt to increase output to maintain a constant air pressure and regain the structural integrity of SCP-XXXX-A (see addendum XXXX-e).
Decompression scenario:
Attempts to introduce digital photographic, GPS, or audio-visual equipment into SCP-XXXX-A results in the rapid decompression of the structure (see addendum 4877-b). The structure will then re-inflate over a period of 30 minutes. The decompression phase appears to be carried out by the reversing of the air pumps, and as of yet there is no method of manually overriding this protocol.
Current actions that induce a decompression protocol within SCP-XXXX
- Introduction of electronic audio-visual or measurement equipment past the airlock component of SCP-XXXX-A
- Attempts to remove/damage vinyl material from SCP-XXXX-A
- Attempts to interact with/remove instances of SCP-XXXX-B
- Attempts to interact with instances of SCP-XXXX-C within Zone Theta.
Investigations into SCP-XXXX have therefore taken place without electronic equipment. Instead, personnel use fibre trails to track their path through the installation and return to the airlock. Due to the inability to use audiovisual equipment, artistic sketches have been made of the more anomalous chambers further within the installation to help plot the internal structure. However, due to the mutating nature of the more extreme zones, a definitive map cannot be plotted of the structure. Instead, researchers have created zones within the installation that share particular characteristics. As a general rule, the chambers become more anomalous the more units away from the airlock are undertaken.
SCP-XXXX Zoning Table
Zone: SCP-XXXX-AX (also mentioned within documents as; tent/ tent-structure/ airlock)
Distance from airlock in units: N/A
Chamber structure, deviation index: The tent structure is a 5x5x5 airlock with an interior and exterior zip to facilitate the airlock function. DI:0
Colour Scheme: Greyscale
Air pump: An iteration of SCP-XXXX-B that appears to function separately to the rest of the studied examples. Designated SCP-XXXX-BX, the air pump functions to equalise the airlock pressure during entry and exit.
Comments: The only externally visible portion of SCP-XXXX-A.
Zone: Alpha (Α)
Distance from airlock in units: 1 – 4 units
Chamber structure, deviation index: Regular polygon. DI:0
Colour Scheme: Primary colours (blue, green, red, yellow)
Air pump: n-3
Comments: None
Zone: Beta (Β)
Distance from airlock in units: 3 – 8 units
Chamber structure, deviation index: Regular polygon. DI:0
Colour Scheme: Secondary colours
Air pump: n-3
Comments: None
Zone: Gamma (Γ)
Distance from airlock in units: 7 – 15 units
Chamber structure, deviation index: Regular polygon. DI:0
Colour Scheme: Gradient colours that appear to merge into one another within the same chamber.
Air pump: n-3
Comments: None
Zone: Delta (Δ)
Distance from airlock in units: 16 units
Chamber structure, deviation index: Regular polygon. DI:0
Colour Scheme: Greyscale
Air pump: n
Comments: Delta Zone appears to be the only stable area within SCP-XXXX that strictly adheres to its characteristics and location.
Zone: Epsilon (Ε)
Distance from airlock in units: 17 – 38 units
Chamber structure, deviation index: Irregular polygon with consistent chamber height. DI:0.11
Colour Scheme: Chambers in this zone show no consistency in their colour scheme
Air pump: Inconsistent. Within this zone, n=0 up to an observed n+23.
Comments: None
Zone: Zeta (Ζ)
Distance from airlock in units: 34 – 418 units
Chamber structure, deviation index: Irregular polygon with inconsistent chamber height. DI:0.42
Colour Scheme: Chambers in this zone show no consistency in their colour scheme and appear to change when unobserved
Air pump: Inconsistent. Within this zone, n=0 up to an observed n+83. Many pumps in this zone are damaged or have mutated (see addendum 6).
Comments: Chambers in this zone visually and physically degrade as the distance from the airlock increases4. Some chambers are discoloured and appear to be physically damaged by unknown means. In this zone, some passages are blocked by further vinyl and are not possible to be traversed.
Zone: Eta (H)
Distance from airlock in units: 190 – ██████████
Chamber structure, deviation index: There is no consistency between chamber shape. Chambers in this zone appear to mutate and change when unobserved. Some chambers have been observed as wholly spherical, with interconnecting passages that appear to [DATA EXPUNGED]. DI:0.96^3
Colour Scheme: Efforts to record colour data in this zone has thus far been unsuccessful.
Air pump: Damage to chambers in this zone has meant that efforts to record pump information has thus far been unsuccessful. This is presumably because [DATA REDACTED]
Comments: Chambers in this zone visually and physically degrade as the distance from the airlock increases4. Some chambers are discoloured and appear to be physically damaged by unknown means. In this zone, some passages are blocked by further vinyl and are not possible to be traversed.
Zone: Theta (Θ)
Distance from airlock in units: █████████████████
Chamber structure, deviation index: DI: 141`•.¸¸.^^*33/140 (see Operation Polychoron)
Colour Scheme: Efforts to record colour data in this zone has thus far been unsuccessful.
Air pump: No air pumps observed in this zone, instead, [DATA REDACTED]
Comments: Due to experiment 4877-15.a, the O5 council has postponed further exploration of this and further potential zones.
1. Due to the mutating nature of the further zones of the installation, zone data is a ‘general observed characteristic’ and thus far there is no indication of any set formula for these characteristics.
2. A unit is a one chamber. The values refer to the minimum and maximum observed chamber with said characteristics.
3. Due to the inability to use visual recording and measurement technology, the Deviation Index (DI) allows Foundation personnel to monitor the changes in the chamber dimensions using manually taken measurements. A regular chamber (Alpha to Delta) will always have a DI of 0, whereas a chamber of DI 0.27 would deviate on average 27% from the standard regular polygon variant. For example, two chambers may have the same number of surface and indices, yet the DI allows personnel to record the extent of irregularity in certain chambers. It is hoped that this system will help explain the more geometrically anomalous chambers in the later zones, and is generally believed to be a scientifically sound method for explaining █████████████████████████████████████████
4. Report by Dr. Rama Nahidji and Dr. Elias Petersen during the 6th entry to SCP-XXXX
(Begin transmission; 22:19:40)
RH: Yikes, I think we’ll have to make a new designation for this zone. This is looking fairly anomalous; there’s a [….] there’s a massive tear in the vinyl here, but I’m not feeling any pressure leak at all. How many units have we gone in?
EP: I’m counting 53 here. We saw a similar thing on the 4th entry, but I’m pretty sure that was at least 120, 130 units in. There’s definitely a bit of overlap between these zones, which makes recording data a massive nightmare.
RH: Tell me about it, you should have seen Sarah’s (Dr. Sarah Anyemi) reaction when we were told we couldn’t take a barometer past the airlock.
EP: Can you get a closer look at the abrasion on the vinyl?
RH: I’m just seeing darkness behind it, as I said, not getting any pressure differential at all; there’s no leak flowing in or out of the chamber. Control, can we take a bio swab?
Control: We’re gonna have to pull a negative on that one, we’re gonna struggle to complete an en emergency withdrawal 50+ units in if we get a decompression protocol. We’ll schedule a D-class information gather tomorrow.
RH: Alrighty, we’ll proceed through and get some more data. We’ll see if we can get an endpoint for this zone (later designated as Zeta).
EP: Onwards and upwards. Well, forwards and […] forwards I suppose.
(End transmission; 22:20:58)
Addendum 4877-b
On the 5th investigation into SCP-XXXX, 3 Class C personnel entered the airlock with a video camera, a GPS tracking device and a barometer (18:13:22) to begin the first long distance expedition into SCP-XXXX. At (18:14:09), having traversed [5] units of the installation, researcher Dr. Hans Delzer noted ‘a noticeable drop in the air pressure reading [and] a visible depression in the roof of the structure’. By (18:15:30), the roof of the installation had depressed to roughly 50% of the original height and the operations command recommended a full withdrawal from SCP-XXXX. On return to the airlock, the opening of the zip caused a sudden decompression of the structure. After exiting SCP-XXXX, two researchers were admitted to a hyperbaric chamber to remedy moderate effects of decompression sickness.
A further 4 repeated experiments using these devices caused the same decompression scenario in the installation. Using barometric equipment to measure pressure differentials, it has been deduced that;
- There is at least one [1] other external connection within SCP-XXXX-A
- This external connection is located roughly ███ units from the contained airlock within SCP-XXXX
Addendum 4877-e
Following the studies that resulted in a decompression scenario within SCP-XXXX-A, further tests were ordered on the pressure-producing capabilities of SCP-XXXX-B. Barometric equipment was installed outside the chamber (control), and also within the chamber to observe the change in pressure. As part of the experiment, the airlock zip was intentionally left open by two class C personnel who remained within the chamber but outside of SCP-XXXX. Between (12:55:13) and (12:57:00) the pressure in the containment cell increased to 40 atmospheres, roughly equivalent to 400m below sea level. Due to a further increase in pressure, at (12:59:16) both of the class C personnel remarked that they were experiencing ‘painful headaches’ and ‘extreme aching in their extremities’. At (13:01:14), the pressure warning system (PWS) within the chamber alerted the operations team that pressure had reached a critical level (70 atmospheres) within the chamber and the class C personnel were order to seal the airlock zip. After the emergency containment chamber decompression had completed, both class C personnel were treated in the Foundation hyperbaric chamber for extreme decompression sickness.
