ceiling
https://www.textures.com/download/concretedirty0246/41567 (image 1, ConcreteDirty0246_11)
https://www.textures.com/download/grungemaps0154/106581 (image 1, Grungemaps0154_3)
https://www.textures.com/download/concretedirty0356/79596 (image 1, ConcreteDirty0356_9)
https://www.textures.com/download/concretenew0063/120692 (image 1, ConcreteNew0063_2)
custom license, https://www.textures.com/terms-of-use.html

door_big
https://www.textures.com/download/doorsmetalbig0287/97881 (image 1, DoorsMetalBig0287_1)
https://www.textures.com/download/decalleakingrusty0021/107252 (image 1, DecalLeakingRusty0021_1)
https://www.textures.com/download/grungemaps0053/13560 (image 1, Grungemaps0053)
custom license, https://www.textures.com/terms-of-use.html

door_small
https://www.textures.com/download/doorssinglerusted0095/81547 (image 1, DoorsSingleRusted0095_1)
custom license, https://www.textures.com/terms-of-use.html

doorframe
https://www.textures.com/download/plywoodpainted0057/59134 (image 1, PlywoodPainted0057_1)
custom license, https://www.textures.com/terms-of-use.html

doorframe_bottom
https://www.textures.com/download/plywoodpainted0057/59134 (image 1, PlywoodPainted0057_1)
https://www.textures.com/download/woodplankspainted0332/114077 (image 2, WoodPlanksPainted0332_2)
custom license, https://www.textures.com/terms-of-use.html

dswp_blue, dswp_red
hand-drawn text by JRandomNoob
public domain / Creative Commons 0, whichever applies
https://en.wikipedia.org/wiki/Public_domain
https://creativecommons.org/publicdomain/zero/1.0/legalcode
masked with
https://www.textures.com/download/concretedirty0246/41567 (image 1, ConcreteDirty0246_11)
custom license, https://www.textures.com/terms-of-use.html

floor, floor_edge
https://www.textures.com/download/concretedirty0246/41567 (image 1, ConcreteDirty0246_11)
https://www.textures.com/download/concretemossy0090/87217 (image 1, ConcreteMossy0090_7)
custom license, https://www.textures.com/terms-of-use.html

glass
screenshot by JRandomNoob
public domain / Creative Commons 0, whichever applies
https://en.wikipedia.org/wiki/Public_domain
https://creativecommons.org/publicdomain/zero/1.0/legalcode

painted_metal
https://www.textures.com/download/rustpaint0164/30049 (image 1, RustPaint0164_1)
custom license, https://www.textures.com/terms-of-use.html

splodey
https://commons.wikimedia.org/wiki/File:Triangle_warning_sign_%28black_and_yellow%29.svg
by Fry1989
public domain
https://en.wikipedia.org/wiki/Public_domain
http://en.wikipedia.org/wiki/File:Hazard_E.svg
by Matthias M.
public domain
https://en.wikipedia.org/wiki/Public_domain
masked with
https://www.textures.com/download/concretewornpaint0097/59242 (image 1, ConcreteWornPaint0097_1)
custom license, https://www.textures.com/terms-of-use.html

svarox
hi sva:-)

wall
https://www.textures.com/download/concretenew0037/28252 (image 1, ConcreteNew0037_2)
https://www.textures.com/download/concretebunker0190/65047 (image 1, ConcreteBunker0190_1)
https://www.textures.com/download/decalbottom0033/93547 (image 1, DecalBottom0033_1)
https://www.textures.com/download/decalssubtle0015/107897 (image 1, DecalsSubtle0015_1)
https://www.textures.com/download/decalleakingrusty0002/52572 (image 1, DecalLeakingRusty0002_1)
https://www.textures.com/download/grungemaps0175/130464 (image 1, Grungemaps0175_1)
https://www.textures.com/download/decalleakingrusty0013/93534 (image 1, DecalLeakingRusty0013_1)
https://www.textures.com/download/plasterwhitedirty0171/66584 (image 1, PlasterWhiteDirty0171_1)
masked with
https://www.textures.com/download/concretewornpaint0093/53943 (image 1, ConcreteWornPaint0093_1)
https://www.textures.com/download/plasterwhitedirty0182/8818 (image 1, PlasterWhiteDirty0182)
https://www.textures.com/download/plasterwhitedirty0276/113911 (image 1, PlasterWhiteDirty0276_2)
custom license, https://www.textures.com/terms-of-use.html

windows, windows_overlay
https://www.textures.com/download/windowsindustrial0347/61038 (image 1, WindowsIndustrial0347_1)
custom license, https://www.textures.com/terms-of-use.html