If you are responsible for managing a portfolio of assets, then your team need AD4s to help them. What does the acronym AD4 mean? Well, it stands for Asset Data Dictionary Definition Document – quite a mouthful, hence the shorter term AD4. What is an AD4? Well, read on….
The AD4 acronym was ‘born’ during the Crossrail programme in conversation between myself and Ross Dentten and is now being used extensively across the programme to communicate asset information requirements to a wide variety of stakeholders. Subsequently, the AD4 acronym has been picked up by many other organisations globally and, whether you use the actual acronym or not, you should understand the purpose of an AD4.
Why do we need AD4s?
Asset intensive organisations (such as airports, water, electricity and gas utilities) typically have many assets of many types spread over a large geographic area. They also use a large team of employees, contractors and other parties to manage these assets. To ensure that data is gathered, stored and used consistently, it is essential that all these stakeholders understand and treat data the same.
Without clear definitions, asset data will be recorded differently leading to ongoing data quality and asset management problems. Some illustrations of the type of problem:
- Is a shunt a length of wire joining two electrical contacts or the movement of a rail freight vehicle?
- Is a table a piece of furniture or a collection of records in a database?
- Is the length of a sheet pile wall the overall horizontal length of the wall or the vertical length of a pile? Is length measured in mm or m?
- Is the diameter of a pipe the internal or external diameter? Is it measured in mm or m?
Depending on how it has been set up, a data dictionary should include this information but may not present it in an accessible way for stakeholders across the organisation. This is where an AD4 comes in.
An example AD4
Something that most of us still use (well, occasionally in some cases) is a ball point pen, so what might an AD4 for a ball point pen look like?
|Class Name||Ball point pen|
|Description||A manual writing instrument using an internal ink reservoir with a small rotating metal ball dispensing ink onto the writing surface. The pen may be disposable or use replaceable refills. The pen may include a removable cap and/or have a retractable point|
|What it is not||Pens using fibre tips or metal nibs to transmit ink to the writing surface. Pencils or other writing instruments where the ink or marking material directly contacts the writing surface|
|Related to||FP001 Fountain pen, PE002 Pencil, PA032 Paper, TP001 Typewriter|
|Make||Allowable values – Bic, Parker, Rotring, Schaeffer, Cross, Waterman, Other|
|Colour||Allowable values – Black, Blue, Red, Green, Other|
|Length||Overall length of pen, excluding cap, measured in millimetres|
|Weight||Overall weight of pen, excluding cap, measured in grammes|
|Retractable||Allowable values – Yes, No|
|Refill type||Allowable values – D1, Parker, Euro, Cross, Schmidt, Other, None|
Storing and publishing AD4s
End users want to understand what data relates to a particular type of asset, and even what type an asset actually is. Usually it is easiest if all the information on a particular type of asset is presented at the same time in the form of a single ‘document’. This makes it easier for someone to check they are referring to the correct class of asset (e.g. a ball point pen rather than a fountain pen) but also to compare attribute definitions at the same time (e.g. to understand what the length, width and depth of a stapler actually refer to). Presenting all this information as if it were a single ‘document’ is a user friendly way to display this information.
Data dictionaries continue to change as new classes of asset are identified, additional attributes are required etc. If end-users have struggled to record data correctly, this indicates that you need to expand the description of what an asset/ attribute represents, even if the underlying data requirement is unchanged.
Although users often prefer to view this information as if it were a document, the ongoing changes to the data dictionary mean that it would be almost impossible to keep a large number of documents up to date. Therefore, it is usually best to store the information in the Asset Data Dictionary in a specific database, but present the final information to users as if it were a document.
Benefits of AD4s
An AD4 does not change the data requirements for an organisation, however, it does ensure that they are more accessible to end users. This can lead to the following benefits:
- Increased likelihood that data will be populated
- Reduced likelihood of asset being incorrectly classified
- Reduced likelihood of attributes such as ratings, dimensions etc. being recorded correctly
- Improved decision making arising from better quality data
- Reduction in poor decisions arising from incorrect data
We have extensive experience in defining, developing and managing data dictionaries. If you want to have a chat about how we can help resolve your data definition challenges, get in contact.