Subclass of:

• crmsci:S18 Alteration
• crm:E7 Activity

Superclass of:

• crm:E12 Production
• crm:E79 Part Addition
• crm:E80 Part Removal
• crmdig:D7 Digital Machine Event

Scope note:

This class comprises all instances of E7 Activity that create, alter or change E24 Physical Man-Made Thing.

This class includes the production of an item from raw materials, and other so far undocumented objects, and the preventive treatment or restoration of an object for conservation.

Since the distinction between modification and production is not always clear, modification is regarded as the more generally applicable concept. This implies that some items may be consumed or destroyed in a Modification, and that others may be produced as a result of it. An event should also be documented using E81 Transformation if it results in the destruction of one or more objects and the simultaneous production of others using parts or material from the originals. In this case, the new items have separate identities.

If the instance of the E29 Design or Procedure utilized for the modification prescribes the use of specific materials, they should be documented using property P68 foresees use of (use foreseen by): E57 Material of E29 Design or Procedure, rather than via P126 employed (was employed in): E57 Material.

Examples:

• the construction of the SS Great Britain (E12)
• the impregnation of the Vasa warship in Stockholm for preservation after 1956
• the transformation of the Enola Gay into a museum exhibit by the National Air and Space Museum in Washington DC between 1993 and 1995 (E12, E81) 
• the last renewal of the gold coating of the Toshogu shrine in Nikko, Japan

In First Order Logic:

• E11(x) ⇒ S18(x)
• E11(x) ⇒ E7(x)

Outgoing properties:

• crm:P31 has modified (was modified by) (0,n:1,n) → crm:E24 Physical Man-Made Thing
• crm:P126 employed (was employed in) (0,n:0,n) → crm:E57 Material