EN ISO 4373:2008

Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 Instrument specification
  4.1 Performance classifications
  4.2 General
  4.3 Maximum rate of change
  4.4 Environment
  4.5 Timing
5 Recording
  5.1 Chart recorders
  5.2 Data loggers
6 Enclosure
7 Installation
8 Estimation of measurement uncertainty
  8.1 General
  8.2 Type-A estimation
  8.3 Type-B estimation
  8.4 Level measurement datum
  8.5 Combining primary measurement uncertainties
Annex A (informative) - Types of water level measuring devices
      A.1 Reference gauges
      A.2 Peak level gauges
      A.3 Mechanical float and counterweight gauges
      A.4 Air reaction gauges
      A.5 Electrical pressure transducers
      A.6 Echo-location, acoustic instruments
      A.7 Echo-location, radar instruments
      A.8 Systems using electrical properties
      A.9 Recording device
Bibliography

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.