Do steel doors need smoke seals? There is a seal around the door set at my work place but a seal is missing on one side. Is this a smoke seal or acoustic seal.

The requirement for smoke seals is based on the needs in terms of fire strategy at the building. For example, fire escape routes would benefit greatly from restricted spread of smoke as would sleeping areas.

Having the door type (steel/timber) alone reveals nothing about any requirement for smoke seals.

As said it depends on location. Protecting an escape route is a common situation where a door would need smoke seals.