The Measuring Instruments (Gas Meters) Regulations 2006

Definitions

2.  In this Schedule—

“base conditions” means the specified conditions to which the measured quantity of gas is converted;

“climatic environments” means the conditions in which relevant instruments may be used;

“critical change value” means the value at which the change in the measurement result is considered undesirable;

“disturbance” means an influence quantity having a value within the limits specified in the appropriate requirement but outside the specified rated operating conditions of the relevant instrument. An influence quantity is a disturbance if for that influence quantity the rated operating conditions are not specified;

“influence quantity” means a quantity that is not the measurand but that affects the result of measurement;

“MPE” means the maximum permissible error value as set out in paragraph 13;

“measurand” means the particular quantity subject to measurement;

“minimum flowrate” (“Qmin”) means the lowest flowrate at which the relevant instrument provides indications that satisfy the requirements regarding MPE;

“maximum flowrate” (“Qmax”) means the highest flowrate at which the relevant instrument provides indications that satisfy the requirements regarding MPE;

“overload flowrate” means the highest flowrate at which the relevant instrument operates for a short period of time without deteriorating;

“rated operating conditions” means the values for the measurand and influence quantities making up the normal working conditions of a relevant instrument; and

“transitional flowrate” (“Qt”) means the flowrate occurring between the maximum and minimum flowrates at which the flowrate range is divided into two zones, the “upper zone” and the “lower zone”. Each zone has a characteristic MPE.