Table 1: The elements of an address

To have a shared set of terms and concepts that are well known to everybody involved in addressing, this chapter provides a short introduction to the elements of street addresses that are used to “compose” the formal system introduced in ‎0 below.

The table on the right shows the written representation of an imagined address for a flat in Wilayat Bawshar in Muscat Governorate. This written address is used as a starting point for the walkthrough of the elements of an address. Please note that this chapter only introduces the typical elements of an address and does not state how each of these will be used. This information may be found in chapter ‎0 below.

For each element, a sub-heading follows which defines the terms and elaborates upon their meaning.

Elements are divided into two categories: mandatory and optional elements. Mandatory elements are essential to the addressing system, optional elements may add value when used in speech among people who are familiar with a city— but may also lead to unnecessary complexity as discussed later in this report.

Elements are presented in descending order by the spatial resolution they represent, i.e. from large to individual sub-address unit locations, i.e. a subdivision inside a building.

Country is only a mandatory element if providing an address for international use, outside of the country that the address is located in. It qualifies the area in which the addressing system is valid.

The administrative validity area of an address identifies the area in which the address must be unique. Typically, this coincides with the jurisdiction area of the public authority responsible for addressing in an area, i.e. a municipality in many countries.

Synonyms for administrative validity area include “address jurisdiction area” (in cases where the addressing is made into law).

Synonyms used in addressing vocabulary includes “area”, “city”, “place” or “town”.

The policies and rules for this element for the National Addressing System (NAS) are given in chapter ‎4.2 below.

The street identifier is the name, number or combination of name and number of a street. The identifier should be unique within the mandatory addressing elements. As an example, no two streets can have the same name within the administrative validity area of the addressing system.

To keep addresses short and usable, it is common practice to keep street identifiers unique within an entire administrative validity area. This way, any user of the addressing system only needs to two elements to identify a location uniquely: the address unit identifier and the street identifier, e.g. “32, Mazoun Street”.

Synonyms for street identifier include “street name”, “street number” (for systems where streets have numbers rather than names) and “street”.

The policies and rules for this element for the NAS are given in chapter ‎4.5 below.

The address unit identifier is a code that specifies the location of an address along a street, or within an area. The address unit identifier is usually assigned based on an offset from the starting point of a street following a metering principle as this ensures that it is easy to assign a systematic address to any new building along a street and that numbers will always be allocated in sequential order.

Address unit identifiers are typically assigned to main entrances to buildings or gates to unbuilt properties including vacant plots, parks and similar. A single building may also have more than one address unit if it is large and have several distinctive functions.

A function in this context could be e.g. commercial and residential.

Synonyms for address unit identifier include “house number”, “building number” and “address number”.

The policies and rules for this element for the NAS are given in chapter ‎4.6 below.

This element is mandatory on when an address refers to sub-units within multi dwelling units (MDUs) such as apartment building.

A sub-address unit identifier is used when the address unit identifier is assigned to an MDU where more than one delivery point (DP) for goods, people and services are accessible through the same entrance.

Examples of MDUs include sub-divided residential villas, closed compounds, residential high-rise buildings, commercial complexes and offices.

Synonyms for sub-address unit identifier include “flat number”, “villa number” (in closed compounds), “apartment number”, “office number” and “shop name/number”.

Guidelines on when and how sub addresses should be created.

The recipient’s name is the name of a legal or physical person or other recognizable entity who resides at a given address. This addressing element is not subject to standardization. This information is temporal and has no bearing on the addressing system.

Elements are presented in descending order by the spatial resolution they represent, i.e. from large to smaller areas.

The post code is a numeric or alphanumeric code facilitating sorting and/or distribution of mail. In postal administrations where mail is delivered to post office boxes, the post code typically identifies the location of the post office.

In postal administrations where mail is delivered to homes, post codes typically identify an area or in some cases a street or even an individual building. With new transport modes and improved distribution efficiency, the main purpose of contemporary post codes is to facilitate automatic sorting of mail. Thus, a sequence of characters that is short, legible and easy to interpret using optical char recognition (OCR) technology is the key requirement. See also ‎1.4.4 below.

The policies and rules for this element for the NAS are given in chapter ‎4.3.

This element is often encountered in address forms and is reserved for any additional useful information. This line is not mandatory and does not add any precision to the address but can be included by the user subject to what he or she thinks useful for the party who is going to interpret the address.

There are no absolute rules dictating the usage of this element in the NAS but practical examples of its use for optional elements is given in chapter ‎4.1 below.

In addition to the human readable elements described above, the NAS also has a few identifiers that are relevant for data management but that are not intended to be seen by end-users. These are described below.

A unique system generated code that identifies an area

A unique system generated code that identifies a street

A unique system generated code that identifies an address unit

An address code is a short number or alphanumeric string that identifies the unique numerical identifier or geographical location of a single address rather than an area, a street or a portion of a street.

Address codes are derived by applying an algorithm to the geographical location of an address unit point or to its unique system generated ID.

Address codes differ from other information system elements in that they have two purposes:

1. Internal: they may be used as database keys in databases or part of persistent uniform resource identifiers (PURIs) in semantic data structures.
2. External: they may be used as a supplement, verification measure or replacement for physical street addresses through their compactness and complexity

An address code may be identical to or distinctive from a post code. Address codes do not exist for all addressing systems. The policies and rules for this element for the NAS are given in chapter ‎4.4 below.