IS 13620:1992 is the Indian Standard (BIS) for general requirements for surveying instruments. This standard specifies the general and performance requirements for surveying instruments like theodolites, levels, and tacheometers. It covers materials, workmanship, optical characteristics, accuracy standards, and testing procedures to ensure the quality and reliability of the equipment for survey work.
Lays down general requirements applicable to all types of surveying instruments regarding their design, construction, and performance.
BIM-relevant code. See the BIM Hub for ISO 19650, IFC, and LOD/LOIN frameworks used alongside it.
| Parameter | IS Value | International | Source |
|---|---|---|---|
| Approach to Instrument Accuracy | Prescribes maximum permissible errors for different classes of instruments (e.g., max 20" collimation error for a Normal Precision Theodolite). | Provides a statistical field procedure to determine the 'standard deviation of a direction' as a measure of precision. No limit is set by the standard. | ISO 17123-3:2001 |
| Operating Temperature Range | Specifies a mandatory range, typically -20°C to +50°C. | Not specified in the testing standard. It is a manufacturer-declared parameter, tested under ambient field conditions. | ISO 17123-1:2014 |
| Ingress Protection (Water/Dust) | Uses descriptive terms like 'drip-proof' and 'dust-protected'. | Uses the specific, test-based Ingress Protection (IP) Code system, e.g., 'IP55' or 'IP67'. | IEC 60529 (Referenced by Manufacturers) |
| Compensator Accuracy (Automatic Levels) | Specifies a maximum setting error, for example, ±0.5 arc-seconds. | Provides a procedure to determine the standard deviation of compensation; acceptance criteria are left to the user or project. | ISO 17123-2:2001 |
| Vertical Axis Stability | Specifies a maximum permissible deviation (e.g., max 1" per 3 minutes of time) after clamping. | Focuses on determining the standard deviation of zenith angles in the test procedure, which implicitly tests overall stability. | ISO 17123-3:2001 |
| Test Documentation | Requires the manufacturer to provide a test certificate confirming compliance with the standard. | The standard itself is the procedure; it provides a format for recording and reporting test results to prove the instrument's performance at a specific time. | ISO 17123-1:2014 |