Lyophiliser (freeze dryer)
Freeze dryer · Lyo · Lyophilisation chamber · Automated loading and unloading system
The chamber that freezes partially stoppered product and dries it under vacuum, then stoppers it — kept sterile, leak-tight and loaded under grade A throughout.
What this page does not claim
An equipment family page teaches how a kind of equipment works and how it is assured. It is not a qualification of any site’s equipment, sets no universal limits, and was checked by SPEQ against the sources it lists, not by an independent engineer.
WHAT IT DOES
A lyophiliser freezes product on temperature-controlled shelves, removes ice by sublimation under vacuum (primary drying) and bound water by desorption (secondary drying), then closes the vials by pressing the stoppers home inside the chamber. Until then the vials are open, so loading and the chamber are part of the aseptic process.
Annex 1 asks that the chamber and its equipment be sterilised to a validated process, that the maximum permitted air leakage be specified "and checked at the start of every cycle", and that the filter maintaining chamber integrity be sterilised before each use with its integrity result part of batch release (8.122, 8.124).
Where it sits: After filling with partially seated stoppers, before capping and inspection.
WHERE YOU FIND IT
- Lyophilised injectable products
- Biologics and other products unstable in solution
In the reference facility: Aseptic filling & isolator line
Not covered on this page: Cycle development and formulation; Bulk freeze drying of non-sterile materials.
MAJOR COMPONENTS
- Product chamber with temperature-controlled shelves. Freezes and heats product; shelves move to stopper the vials at the end of the cycle.
- Condenser. Traps water vapour as ice.
- Vacuum pumps and control valve. Set chamber pressure for drying.
- Sterile vent filter. Admits gas to break vacuum; sterilised before each use and integrity tested (Annex 1, 8.124).
- Steam-in-place system. Sterilises the chamber and condenser; monitored at locations correlated with the slowest to heat (Annex 1, 8.63).
- Loading and unloading system. Moves open vials under grade A, preferably automated or behind barriers (Annex 1, 8.123, 8.126).
Connects to: Filling line; Clean steam and process gases; Isolator or RABS around loading; Capping line.
INSTRUMENTS AND WHAT THEY MEASURE
- Temperature sensor (RTD or thermocouple). Shelf, condenser and, where used, product temperature. Watch for: sensor not at the location that matters (cold spot, load centre).
- Pressure transmitter (gauge or absolute). Chamber pressure; capacitance and thermal-conductivity (Pirani) gauges read differently in water vapour. Watch for: gauge and absolute values compared directly.
- Filter integrity tester. Vent filter integrity for batch release (Annex 1, 8.124). Watch for: membrane not fully wetted, giving a false failure.
PARAMETERS
SETPOINT · MEASURED · LIMIT · ATTRIBUTE- Temperature (setpoint, °C). Shelf temperature by phase, from the product’s validated cycle.
- Chamber or vessel pressure (setpoint, bar a or bar g or kPa). Absolute pressure during drying, from the validated cycle.
- Chamber vacuum leak rate (limit, mbar/min or kPa/min). Maximum permitted air leakage specified by the site and checked at the start of every cycle (Annex 1, 8.124).
- Sterilising filter integrity result (limit, bar or psi (bubble point) or mL/min (diffusion, water intrusion)). Vent filter result against the limit validated for the process, part of batch certification (Annex 1, 8.124).
- Residual moisture (attribute, % w/w). In the dried product, against the product specification.
SPEQ publishes no universal alarm or acceptance values: they depend on the process, the product and the site’s own qualification.
CONTROLS, ALARMS AND INTERLOCKS
- Control loop: Shelf temperature and chamber pressure control. Follows the validated cycle recipe.
- Interlock: Leak test before cycle start. Holds the cycle if the leak rate is above its limit (Annex 1, 8.124).
- Procedure: Sterilisation frequency. Before each load if loaded manually without barriers; otherwise justified in the CCS; and after maintenance or cleaning (Annex 1, 8.122, 8.123).
- Procedure: Tray checks. Trays checked regularly for distortion or damage (Annex 1, 8.125).
An alarm asks for a response; an interlock stops an action; a safety function protects people and has its own risk basis.
HOW IT FAILS
- Chamber leak. Non-sterile air drawn over open vials, and drying conditions lost.
- Open vials exposed during transfer. Contamination outside grade A (Annex 1, 8.126).
- Product temperature above its critical temperature. Cake collapse or meltback.
- Distorted trays. Uneven heat transfer and stoppering.
- Condenser overload. Loss of pressure control in primary drying.
ASSURANCE ACROSS THE LIFECYCLE
EXAMPLES, NOT A MANDATORY LIST- Qualification. Shelf temperature uniformity; Leak rate and vacuum performance; SIP validation of chamber and condenser (Annex 1, 8.63).
- Process validation. Cycle performance across the load; APS covering loading, hold times and unloading (Annex 1, 8.122).
- Each batch. Leak rate at cycle start; Vent filter integrity; Cycle record and residual moisture results.
- Periodic. Sterilisation per the justified frequency; Tray inspection.
WHAT THIS DOES NOT PROVE
- A shelf temperature trace on target does not prove the product stayed below its critical temperature. Instead: Product temperature data or pressure-rise tests, against cycle development.
- A passing leak test at cycle start does not prove integrity through the cycle. Instead: Pressure control trends and the vent filter result.
- A sterilised chamber does not prove the vials stayed protected during loading. Instead: APS covering the transfer and grade A monitoring during loading.
SOURCES
2 CITED- EU GMP Annex 1: Manufacture of Sterile Medicinal Products — European Commission (EudraLex Volume 4), 2022 revision, in operation 25 August 2023. EU / EEA; revised jointly with the PIC/S Committee; in force. Supports: Air removal for lyophiliser chambers (8.61); steam-in-place (8.63); sterilisation and its frequency (8.122, 8.123); integrity, vent filter and leak testing (8.124); trays (8.125); loading and transfer (8.126).
- EU GMP Annex 15: Qualification and Validation — European Commission (EudraLex Volume 4), 2015. EU / EEA; in force. Supports: Equipment qualification and process validation approach.
HOW THIS PAGE WAS CHECKED
Researched and checked against the sources above by SPEQ (Claude) on 2026-10-21. It has not been reviewed by an independent engineer. It teaches how this kind of equipment works and is assured; it does not say any site, asset or process is qualified, validated or compliant.
- Cycle parameters are product-specific and no figures are given.
Spotted something wrong? Tell us.