Scale

Scale is the ratio between a length on a map or plan and the corresponding length in reality. Scale allows understanding how large an area is depicted and with what level of detail.

Scale notation:

• Numeric scale - ratio 1:500 means 1 cm on plan equals 500 cm (5 m) in reality
• Linear scale - graphic bar scale with markings
• Verbal scale - "one centimeter equals five meters"

Scales used in surveying:

• 1:250 - highly detailed plans, urban construction
• 1:500 - standard topographic plans for construction
• 1:1000 - larger areas, detailed plans
• 1:2000 - village and city plans
• 1:5000 - parish territories
• 1:10000 - municipality maps

Scale selection:

Scale selection is determined by:

• Type of task - construction requires larger scales
• Territory size - smaller scales for larger areas
• Required detail - larger scale for utilities
• Regulatory requirements - minimum scales specified for construction

Scale impact on precision:

The larger the scale (smaller number), the:

• More precisely details can be depicted
• Smaller graphic error
• More precise measurements required
• More sheets needed for large areas

Digital plans:

In modern digital plans, scale is nominal - data can be viewed at any zoom level. However, the plan is developed for a specific scale, which determines measurement precision and detail level.

Graphic precision:

It is accepted that the human eye can distinguish lines at least 0.1 mm apart. Therefore, graphic precision at 1:500 scale is 0.1 × 500 = 50 mm or 5 cm in reality.