Music Library Association Best Practices for duration

Routinely record the element for audio and video recordings if readily ascertainable. Routinely record the element for notated music only if the resource described explicitly provides an intended or approximate performing time.

In MARC: Record using one or more appropriate fields based on the type of resource:

• identifier: 008/18-20 or 006/01-03 (video)
• unstructured: 300 $a (audio or video; record after extent, enclosed in parentheses)
• structured: 306 $a (any resource)
• unstructured: 505 second indicator blank $a (aggregates, as part of a contents note)
• unstructured: 505 second indicator 0 $g (aggregates, as part of a contents note)
• unstructured: 500 (any resource)

In MARC: Apply the option for unstructured descriptions.

In MARC: Apply the option for unstructured descriptions.

Apply the option if total duration is not readily ascertainable. If only the durations of parts or aggregated expressions are provided, use cataloger's judgment in deciding what is readily ascertainable.

In MARC: Record multiple durations in fields 306, 505, or 500.

In MARC: Record total duration in fields 006, 008, 300, 306, or 500.

Apply the option if feasible.

In MARC: Do not record both a total duration and the durations of parts or aggregated expressions in field 306. Prefer field 306, if used, for multiple durations and another appropriate field for total duration.

Apply the option if total duration is not readily ascertainable. If only the durations of parts or aggregated expressions are provided, use cataloger's judgment in deciding what is readily ascertainable.

In MARC: Record multiple durations in fields 306, 505, or 500.

In MARC: Record total duration in fields 006, 008, 300, 306, or 500.

Apply the option if feasible.

In MARC: Do not record both a total duration and the durations of parts or aggregated expressions in field 306. Prefer field 306, if used, for multiple durations and another appropriate field for total duration.