Gives guidance on the provision of reactor instrumentation and recommends standard of good practice. The main body of the Recommendation is of general application and aspects applicable only to particular types of reactors are included in Appendices (under consideration). Items of instrumentation are included only where they have a direct bearing on the over-all safety and effective control of the reactor. In detail, the considerations are concerned with: neutron flux measurement, temperature measurement, coolant measurements, protection systems, power supplies for instrumentation, control facilities, and general alarms.