What you’re looking at is a small piece of Bushwick. The maroon colored squares are buildings with 27 or more uncorrected housing code violations and more than five violations per unite. The pink ones have between 3.5 and 5 violations per unit. You can now see this kind of thing thanks to a housing code violation overlay on the maps at Property Shark. (For every block in the city.) Take, for instance, 235 Troutman Street in Bushwick, which has 227 violations. Things like these, in the words of the violations themselves:

Provide ready access to buildings heating system no access door locked at cellar…Repair the broken or defective plastered surfaces and paint in a uniform color ceilling and walls in the bathroom…Remove all obstructions and repair all defects in at bath tub waste pipe in the bathroom…Repair or replace the smoke detector missing in the entire apartment…Provide an approved and operational carbon monoxide detecting device…Repair with similar material the broken or defective fire retardant material ceilings and walls all stories at public hall…Replace with new the broken or defective locking device at the door in the entrance.

And that’s just a sampling of the violations in one apartment in October and December.