Balance and load-cell dispensing system

Weighing sets how much of each ingredient goes into a batch and how much sample goes into a test. Chapter 3 asks that "balances and measuring equipment of an appropriate range and precision" be available for production and control (3.40), and that measuring and weighing equipment be calibrated and checked at defined intervals with records kept (3.41).

Dispensing usually happens in a downflow booth that protects the operator and the material, on balances linked to a system that checks the material, lot and target weight before recording the result.

Where it sits: In the dispensary before formulation, in the laboratory for samples and standards, and under vessels and on lines as load cells.

• —Dispensing of active substances and excipients
• —Laboratory weighing of samples and reference standards
• —In-process fill weight checks
• —Vessel batch weights

In the reference facility: Material staging, weighing & dispensing, QC analytical laboratory, Processing & formulation suite

Not covered on this page: Checkweighers on filling lines, covered on the filling line page.

• 01Weighing cell or load cell. Measures the force of the load.
• 02Terminal and data interface. Shows and records the result, ideally transferred without retyping.
• 03Draught shield or downflow booth. Reduces air movement on the pan and protects the operator.
• 04Reference weights. Calibrated weights used for routine checks.

Connects to: Dispensing or batch management system; Laboratory data systems; Calibration management; Material identification and labels.

• 01Balance or load cell. Mass of ingredients, samples and batches. Watch for: weighing below the balance's minimum weight for the required accuracy.

• 01Weighed mass (measured, g or kg). Against the target and tolerance for each ingredient or sample, on a balance of suitable range and precision (Chapter 3, 3.40).
• 02Temperature (measured, °C). Of the weighing room, where it affects fine balances.

SPEQ publishes no universal alarm or acceptance values: they depend on the process, the product and the site’s own qualification.

• 01Interlock: Material and tolerance check. Blocks recording when the material, lot or weight is outside the target tolerance.
• 02Procedure: Calibration at defined intervals. By appropriate methods, with records (Chapter 3, 3.41).
• 03Procedure: Routine checks before use. Check weights confirm performance between calibrations, at a frequency the site defines.
• 04Procedure: Minimum weight. Each balance is used only above the smallest weight it can weigh to the required accuracy, set by the site from its qualification.

An alarm asks for a response; an interlock stops an action; a safety function protects people and has its own risk basis.

• 01Selection and qualification. Range and precision for the intended weighings (Chapter 3, 3.40); Minimum weight determination.
• 02Calibration. Calibration at defined intervals with traceable weights (Chapter 3, 3.41).
• 03Routine. Pre-use checks; Weighing records linked to material and lot.
• 04Data. Electronic records and audit trails where results are stored electronically.

• 01EU GMP Part I, Chapter 3: Premises and Equipment — European Commission (EudraLex Volume 4), 13 August 2014, in operation 1 March 2015. European Union; in force. Supports: Balances and measuring equipment of appropriate range and precision (3.40); calibration and checks at defined intervals, with records (3.41).