Phosphorus Gas

Phosphorus Gas is a gaseous element that, when present in an area, imparts the Polluted Atmosphere status to that space for gameplay systems that check atmosphere type. Its presence alters how food spoilage and related mechanics operate inside rooms or containers filled with the gas, because the game treats any Polluted Atmosphere uniformly for spoilage calculations.

Food stored or left in an environment composed of Phosphorus Gas is considered to be in a Polluted Atmosphere. Polluted Atmosphere applies the base spoilage multiplier of ×1 to perishable food; combined with temperature-based multipliers, this determines the final spoilage speed and shelf life. Temperature categories interact with atmosphere type as follows: below −18 °C (frozen) a Polluted Atmosphere uses ×1 spoilage multiplier and a shelf life multiplier of ×1; between −18 °C and 4 °C (refrigerated) Polluted uses ×1 spoilage multiplier (with shelf life multiplier ×0.833); above 4 °C (unrefrigerated) Polluted uses ×1.7 spoilage multiplier (with shelf life multiplier ×0.588). Refrigeration and deep-freeze mechanics still apply: a refrigerated body of food (≤ 4 °C) reduces spoilage compared to unrefrigerated, and deep freeze (below −18 °C) can stop atmosphere-driven spoilage entirely, though the specific tables above should be used to compute exact multipliers.

Phosphorus Gas therefore accelerates food spoilage relative to Normal Atmosphere in many temperature bands (Normal Atmosphere often has lower multipliers such as ×0.3 in unrefrigerated or ×0.5 in refrigerated ranges). Because Phosphorus Gas forces the Polluted Atmosphere status, it negates the benefits of Normal or Sterile Atmospheres for food preservation; food in a Sterile Atmosphere would otherwise see spoilage multipliers reduced or removed, but Phosphorus Gas does not count as sterile.

Phosphorus-related solids and liquids appear elsewhere in production and critter interactions: melting Phosphorite yields Liquid Phosphorus, which can be frozen into Refined Phosphorus; Refined Phosphorus is used by certain critters (Azure Bugs, Abyss Bugs) as food and as bait for airborne critters, and is consumed by the Geotuner to influence metal volcanoes. These solid/liquid phosphorus forms are distinct from Phosphorus Gas and have separate mechanics; only the gas form confers the Polluted Atmosphere status described above.

Practical notes and interactions:

• Food stored or transported through an area filled with Phosphorus Gas will spoil at Polluted Atmosphere rates; avoid routing food through or stocking food in rooms with Phosphorus Gas unless temperature is controlled to refrigerated or deep-freeze levels.
• Refrigeration reduces spoilage even in Polluted Atmosphere (use refrigerators, insulated containers, or place food in lower-temperature environments). Deep freeze removes atmosphere-driven spoilage effects if temperatures are below the deep-freeze threshold.
• Sterile Atmosphere benefits do not apply in Phosphorus Gas; it is not listed among gases that count as sterile.
• Treat Phosphorus Gas like any other Polluted Atmosphere for systems that query atmosphere type (venting, disease/spoilage algorithms, and building behavior that differentiates atmosphere categories).