How to Use MS1759?
1. Coding of features and attributes
This standard has not been developed to the requirements of any single application or level of resolution. This standard is also not meant to support any specific digital product. As with any dictionary, there may be more than one way to encode spatial entities, either by offering a choice of features or a combination of features and attributes
For example, an airport is listed as feature AB0010 - Aerodrome
(A defined area on land or water intended to be used either wholly or in part for the arrival, departure and surface movement of aircrafts, could also be coded as feature BD0010 - Institutional Building with attribute INU (Institutional Usage) with a coded value of 001 (Airport Terminal)).
The choice is entirely up to user own application and interpretation; to code only the terminal building or the entire aerodrome area. Feature codes are shown in Annex A and Attribute codes and values are given in Annex B. Annex B also provides information as to the units, formats, ranges, increments and maximum text characters typically associated with each actual value attribute.
If a feature does not reside within this standard, it is allowed for a user-designated features and associated attributes. Otherwise, features and attributes shall be encoded using this standard. The process for amending and updating this standard is described in 2.3.
2. Coding structure
Each feature is identified by a unique six-character code. The first character corresponds to the feature category and can have an alphabetic value from A through Z. Currently there are twelve feature categories, including one category, X, which has been reserved for special use (dataset-specific) features.
Attributes are used to describe characteristics of a feature. Each attribute is described by using attribute codes to represent the category of information. Attribute value format statements provide a computer interpretation for the attribute value data type (e.g. real, alphanumeric) and attribute values give quantitative/qualitative meaning to the attribute code. An attribute can be used by any feature, but care must be taken so that only meaningful attributes are chosen for a particular feature.
For example, syntactically, an attribute "Lift Facilities" can be used with feature "Rail Line", but semantically, the combination is useless. A list of possible attributes for each feature have been provided for the convenient of users.