The Encumbrance of an Item is the awkwardness of the combined size, form, and weight/mass of goods. Measures are assessed against a humanoid being as a baseline. Most small items do not have measurable ENCumbrance on an individual basis, but are measured by groups of related items (Kits) and major items (armor, shields, weapons, etc.). A Physical Conditioning Regimen can also offset these penalties.
Items used by characters must match their Size Factor. If not, worn items cannot be used effectively at all and are automatically encumbering; held items increase by +1 ENC per category greater. If you do not meet the minimum attribute rating for an item the default penalty is +1 ENCumbrance per condition unmet.
Encumbrance Capacity (EC): The maximum Encumbrance you can manage without it affecting your activity.
A character without measurable Encumbrance CAN be Unfettered if they meet all other requirements (unimpeded senses, etc.).
Unencumbered Condition: Load/Encumbrance <= 1x Encumbrance Capacity (EC)
Encumbered Condition: Load/Encumbrance > 1x Encumbrance Capacity (EC)
Direly Encumbered Condition: Load/Encumbrance > 2x Encumbrance Capacity (EC)
Disastrously Encumbered Condition: Load/Encumbrance > 3x Encumbrance Capacity (EC)
While the effects encumbering the character are affecting them, they suffer the following penalties:
EC = Size Factor + Strength mod; Some Features adjust ENCumbrance.
* = Movement adjustments includes penalty from Exhaustion unless zero, but not Difficult Terrain.
Its not the intent to make ENCumbrance an inventory management exercise, but those wishing for good game balance and gritty realism requires it to have some presence.