You could sometimes tell if there were humans nearby, or at least if the space was intended for humans, by the environment.

One sign was of course, food, or any place that revolved around food. Diners and grocery stores, of which there were few, were the places to go to encounter humans and for the most part, humans only.

Then there was the quality of air. Fortunately, even robot-only dwellings usually had some ventilation system. Although constructs didn’t breathe, they did tend to like things clean and orderly. An abundance of dust and a breeding ground for mold wouldn’t do. Besides, the ventilation systems were already built, so they might as well keep them running.

One notable exception of course was a large section of the second level known as Miasma. Not only did the vent system there no longer work, but there was a significant leak of poisonous gasses from the machinery on level 1. An attentive person might be able to see this as a faint yellow glow that hung in the air, with faint swirls of gas illuminated by strong lights. It wasn’t so think that one couldn’t see down the hallway, but it did limit visibility somewhat. Down a particularly long hallway, it was sometimes difficult to see one end from the other.

Not only was the vent system supposed to filter out such gasses, it also maintained the proper humidity levels. Without it, Miasma grew into a very wet place. It was full of mold. But since Vermilion’s entire structure was made of metal and glass, the water and mold posed no real threat to the structural integrity of the area. But it did make it a place unsuitable for mammals, especially fragile, picky ones such as humans.

Though a human could certainly survive entering miasma, and even make a short stop there without much ill effect, a prolonged stay there could be deadly. It was rumored that the construct inhabitants of Miasma had a way of fixing the vent system, but chose not to, in order to discourage the presence of humans. Human-unfriendly factions like the Skinless were known to spend time there.

A less pressing difference was plumbing. In some apartment complexes, there was no water at all. Since constructs didn’t need to bathe, use toilets or cook, water was thought of as a convenience for people who liked to keep things clean, rather than a necessity.

Some constructs even preferred to live in a place without working indoor plumbing. This may be best explained by a page from THESIS’ original manual to the Helpmate.

While the Helpmate(TM) is water resistant, it is not waterproof. They contain steel parts which will rust if neglected, and some connections may short if too wet, which could cause permanent damage. To ensure a long, healthy service life for your Helpmate, please observe the following guidelines.

  1. Never submerge the Helpmate in water or send it out in heavy rain. Light rain shouldn’t cause problems, but we do suggest an umbrella. A patented THESIS umbrella can be found at your local android supply store or through one of our online partners.
  2. If the Helpmate gets significantly wet, turn it off immediately. Dry it with a towel, and then allow it to air dry completely before turning it on again. THESIS is not responsibly for any damage resulting from leaving the Helpmate on when it is wet.
  3. If you have a Helpmate II or Helpmate Porcelain Collection, oil its exposed joints regularly to avoid rust. If light rust has begun, we suggest cleaning it with a scrubbing sponge dipped in alcohol. If the rust is severe, take your Helpmate to a THESIS certified technician.
  4. While we know you’ll do your best to care for your Helpmate, we know accidents can happen. If you would like to purchase an extended care plan to insure against water damage and other mishaps, simply contact a THESIS representative before your warranty expires.

But there was one difference between human and construct sections that was more universal, though not more vital. That was heat.

The entire complex of Vermilion was heated by one system, a massive combination of a boiler and hot water heater, which ran to each section, with shutoff valves for each level and section. It was old, but quite powerful, and provided everyone with more heat and hot water than they could ever use, due to the fact only humans really used these, and it was built to accommodate ten times the human population that currently lived there.

This was shut off in certain apartment complexes and business where only Constructs lived and did business. So when a human entered an area and was hit with a sudden wave of cold, they knew they were someplace where no humans were likely to be found - a place not meant to accommodate them.

A characteristic of levels 3 and 4 was that it was entirely heated. Even the “outdoor” areas were always heated. It was intended to be the right temperature and moisture for human comfort at all times. Plants, too, were meant to thrive here. The ground was cement and therefore had no soil, but there were potted plants here and there, placed strategically under lamps.

There were rumors that the boiler was getting too old and, one day, might stop working altogether. The sounds of the boiler were loud, but distant. A cavernous rumble from the depths below. It could barely be heard on the third floor and not at all on the fourth, but from the second floor, it was clear and distinct.

It was a comforting sound, despite its ominous, echoing quality, as it was what separated the warmth-loving humans within from the cold wilderness without.