Deterioration

Deterioration is the gradual loss of the hit points of certain items. An item is anything that can be hauled by a colonist. Deterioration is akin to an item taking damage from projectiles, explosions, or fire since they all affect the same hit points stat. Affected items include clothing, armor, weapons, and most resources. Deterioration is applied to an item that is not placed in a safe place. An item being in an outdoor area, water, sea, or swamp will trigger the deterioration.

A shelf protects any item. Mountains have an indestructible roof making them well-suited to protect perishable items. But be careful when re-constructing the walls; if the roof collapses, everything underneath will be buried.

When an item's hit points reach 0, it is destroyed.

Special notes

• Deterioration is also applied to apparel (both clothing and armor) when worn.

• A colonist wearing any apparel with hit points 50% or below will get the -3 thought "Ratty Apparel".
• If any worn item is below 25%, the thought will worsen to a -5 "Tattered Apparel".

• A colonist does not receive negative thoughts for using deteriorated weapons.

• Equipped weapons do not deteriorate.

• Artillery shells that deteriorate to 0 hit points will explode.

• Raw food deteriorates in addition to still being prone to spoilage.

• As an item loses hit points, it may also lose its market value. This only applies to items which have not been configured to ignore health when determining price. The XML tag for this is healthAffectsPrice, which defaults to true if not explicitly set in the def or a parent of the def. This is set, for most items, in the base definition which the item inherits from. In the base game, this includes: all drugs, meals (including Pemmican and Kibble), medicine, raw plant matter (ex. Hops, Hay, Corn), raw animal products (ex. Milk, Insect Jelly, eggs), textiles (all leathers, wools, and cloths/threads), as well as Wort, Industrial and Advanced Components, Neutroamine, Chemfuel, and most/all of the basic resources (Wood, Jade, Steel, Uranium, Plasteel, Silver, Gold).

• If an item loses value with hit points, it loses them very quickly. An item retains 100% of its value down to 90% HP, then loses 1.67% of its maximum value per 1% HP lost between 90% and 60% HP, then loses 4% if its maximum value per 1% HP lost between 60% and 50% HP, then loses 0.2% of its maximum value per 1% HP lost between 50% and 0% HP. The item will have 50% of its maximum value at 60% HP and only 10% of its maximum value at 50% HP.

• Other than market value, an item's HP does not affect any other stats, including damage output, accuracy, armor value, heat or cold insulation, nutrition, flammability, beauty, comfort, medical potency or quality, etc. In addition, a finished product is not influenced in any way by the deterioration of its ingredients, including in market value.

Deterioration Rate

An item's deterioration rate specifies how many hit points are lost per day. Depending on the type of item, it ranges from 0.25/d to 10.0/d. This stat is listed in an item's information tab. If this stat is not listed or listed as '0.00/d', then the item will not deteriorate. Rain greatly affects the deterioration rate. For items with the quality stat, a high-quality item will have a lower deterioration rate than a poor quality item.

Immunity

Metal and stone are immune to deterioration. However, items crafted from these materials do not carry over that immunity.
Other immune items:

• AI persona core
• Artifacts
• Minified furniture and buildings

Version history

• In the past, deterioration lowered the effectiveness of weapons and armors, but that is no longer the case.