ISO/TC 113/SC 5 - Instruments, equipment and data management

This document specifies a calibration method for mechanical type, electromagnetic type and acoustic type hydrometric current-meters used for point velocity measurement of flowing water. The method requires towing the instrument through still water in a straight open tank. It includes measuring apparatus, the calibration procedure, the method of presenting the results and the uncertainties associated with the method.

ISO 6420:2016 specifies methods of determining the position of hydrometric boats based on satellite navigation systems and/or with respect to known points on the banks of rivers, estuaries or lakes. It applies to electronic positioning equipment and conventional surveying techniques.

ISO 24155:2016 specifies the technical requirements that should be considered in designing and operating hydrometric data transmission systems (HDTS) and also the necessary functions of those systems. The scope of HDTS is shown in Annex A.

ISO 4375:2014 defines the requirements for equipment, anchorage, supports and accessories for cableway systems for use in stream gauging. Systems which are operated either entirely from the river bank or from a suspended personnel carriage (also called a "cable car") are discussed. Should the cableway installation be required to be certified as lifting equipment, other standards or regulations may apply. ISO 4375:2014 is only applicable to the cableway systems to be used for hydrometric measurements.

ISO 4373:2008 specifies the functional requirements of instrumentation for measuring the level of water surface (stage), primarily for the purpose of determining flow rates. An informative annex provides guidance on the types of water level measurement devices currently available and the measurement uncertainty associated with them.

ISO 3454:2008 specifies the functional requirements of the equipment, excluding bankside cableway systems, used in the measurement of liquid flow in open channels for sounding (by direct method), and suspending the measuring equipment (for example, current-meter or sediment sampler) at the point of measurement.

ISO 1088:2007 provides a standard basis for the collection and processing of data for the determination of the uncertainties in measurements of discharge in open channels by velocity-area methods using current meters. To determine the discharge in open channels by the velocity-area method, components of the flow (velocity, depth and breadth) need to be measured. The component measurements are combined to compute the total discharge. The total uncertainty in the computed discharge is a combination of the uncertainties in the measured components. ISO 1088:2007 is intended to be applied to velocity-area methods that involve measurement of point velocities at a relatively small number of discrete depths and transverse positions in the flow cross-section, as described in ISO 748. It is not intended to be applied to measurements made by Acoustic Doppler Velocity Profilers (ADVP) or other instruments that produce essentially continuous velocity profiles of the flow field.

ISO 4366:2007 provides information concerning the principles of operation, selection and performance criteria for echo sounders used in depth measurements for open-channel flow (and related) measurements. The use of standard terminology is promoted.

ISO 2537:2007 specifies the operational requirements, construction, calibration, and maintenance of rotating-element devices for the measurement of flow velocities in open channels.

Provides a method of specifying the performance of hydrometric equipment. Identifies, within a performance framework, the faktors that affect the range of uncertainty within which the hydrological quantity is converted into a numerical quantity. Applies to all equipment used for hydrological measurement, with the exception of equipment used for the determination of water quality.

Concentrates on the specialized equipment required for gaining access through the ice sheet and obtaining area, velocity, and other information for determining the rate of flow under ice. Does not specify techniques for measurement and computation which are dealt with in various International Standards. ISO 9196 specifically deals with the methods for the measurement of flow under ice and this Technical Report is intended to be used with ISO 9196.

ISO 3455:2007 specifies the procedure of calibration of current-meters of rotating-element type as well as stationary-sensor type (electromagnetic type) in straight open tanks. It also specifies the types of tank, rating carriage and equipment to be used and the method of presenting the results. The procedure does not take into account any possible difference existing between the behaviour of a current-meter moving in motionless water and that of a fixed current-meter in turbulent flow.

ISO/TS 24155:2007 specifies the technical requirements that should be considered in designing and operating hydrometric data transmission systems and the necessary functions of those systems.

ISO/TS 24154:2005 gives the principles of operation, construction, maintenance and application of acoustic Doppler profilers to the measurement of velocity and discharge, and discusses calibration and verification issues. It is applicable to open-channel flow measurements with an instrument mounted on a moving vessel. ISO/TS 24154:2005 is not applicable to measurement of liquid flow in small channels or partly-filled pipes using a single Doppler-based flowmeter at a fixed point in the cross section.

Specifies the functional requirements and operational procedures for stage detecting, encoding and recording devices for measuring water levels in open channels. Replaces the first edition, which has been technically revised.

Specifies the operational requirements, construction, calibration, and maintenance of rotating element devices for the measurement of flow velocities in open channels. Does not define the form of the signal produced by the equipment or the signal receiving equipment. Cancels and replaces the second edition (ISO 2537 : 1985), of which it constitutes a technical revision.

For determining the discharge in open channels by the velocity-area method, components of the flow need to be measured. The total uncertainty in discharge is a combination of the uncertainties in these components. This ISO-Standard specifies a standard basis for collecting and processing the data required to compute the component uncertainties for determining the total uncertainty in discharge.

Specifies methods of determining the position of hydrometric boats with respect to known points on the banks of rivers or estuaries. Applies to conventional surveying techniques and, in recognition of the availability of more sophisticated equipment, describes the principles of operation of currently available electronic positioning equipment.

Specifies functional requirements of sounding and suspension equipment used in the direct measurement of depht and velocity of flow in open channels, including the collection of sediment samples. Does not apply to indirect methods such as echo sounding. This second edition cancels and replaces the first edition (1975).

Provides information concerning the principle of operation, performance and selection criteria for echo sounders used in depth measurements for open channel flow (and related) measurements. The use of standard terminology is promoted. Information on the characteristics of sound in water is provided in annex.

Specifies the procedure to be used for the calibration of current-meters, i.e. for the experimental determination of the relationship between liquid velocity and rate of revolution of the rotating element. Specifies also the type of tank and equipment to be used and the method of presenting the results.