Introduction

A definitive guide to how vertical autoclave systems deliver validated steam sterilization across clinical, research, and pharmaceutical laboratory environments — from instrument processing to waste decontamination.

134°C Peak Temp
Digital PLC Control
Validated Cycles
Gravity & Pre-vac Modes

"Steam sterilization remains the gold standard for decontamination of heat- and moisture-stable instruments, media, and biohazardous waste — and the vertical autoclave is the workhorse instrument delivering that standard across laboratory and medical environments worldwide."

A vertical autoclave is a pressure vessel that uses saturated steam under controlled pressure and temperature to achieve sterilization of laboratory and medical materials. The vertical chamber orientation makes it especially well-suited for tall containers, flasks, and bagged biohazardous waste — load types that horizontal autoclaves cannot accommodate without modification.

The Fison Vertical Autoclave delivers validated sterilization cycles with digital PLC control, temperature accuracy to ±1°C, and programmable cycle profiles for different load types. It serves hospitals, research institutions, pharmaceutical QC labs, and biotechnology facilities where sterility assurance is a regulatory and operational requirement.

How Steam Sterilization Works

The validated autoclave cycle — from loading to sterility confirmation

1
Load & Seal
Items loaded in chamber; door sealed and interlocked. Pre-cycle checks confirm water level and door closure
2
Air Removal
Gravity displacement or pre-vacuum pulse removes air from chamber and load — air pockets block steam penetration
3
Sterilization Hold
134°C / 3 min or 121°C / 15–20 min — saturated steam contacts all surfaces for microbial kill
4
Exhaust & Dry
Steam exhausted; drying phase removes surface moisture from wrapped instruments before chamber opens
5
Cycle Complete
Printout / log confirms cycle parameters met. Biological indicator incubation confirms sterility assurance level (SAL 10⁻⁶)
Sterility Assurance Level (SAL): Validated autoclave cycles achieve SAL of 10⁻⁶ — meaning a probability of less than one in a million that a viable microorganism remains on a processed item. This is the regulatory standard for sterile medical devices (ISO 11135, EN 556).
Temperature & Pressure Parameters

Standard autoclave cycle conditions across load categories

134°C
Peak Sterilization
Prion-effective flash cycle for wrapped instruments and hollow loads using pre-vacuum air removal
121°C / 103 kPa
Gravity displacement — glassware, media, pipettes, unwrapped instruments. 15–20 min hold time
134°C / 206 kPa
Pre-vacuum — wrapped surgical instruments, porous loads, hollow items. 3–5 min hold time
121°C — Waste
Biohazardous waste decontamination — bagged infectious materials, cultures, sharps in safety containers
121°C — Liquids
Agar, culture media, water for injection — slow exhaust cycle prevents boil-over during pressure release
Materials Processed
Surgical InstrumentsGlasswareCulture MediaPipette TipsWrapped PacksBiohazardous WasteTextiles & GownsRubber GoodsHollow InstrumentsLab PlasticwareAnimal BeddingLiquid Media
Key Performance Features

Six core capabilities that define laboratory-grade vertical autoclave performance

01
Digital PLC Control

Programmable Logic Controller manages all cycle phases automatically — temperature ramp, hold, exhaust, and drying. Eliminates manual intervention and operator variability across cycle runs

Cycle Repeatability: ±1°C accuracy
02
Dual Cycle Modes

Gravity displacement for media, glassware, and waste — pre-vacuum mode for wrapped porous and hollow loads. Switchable via front panel for load-appropriate sterilization

Load Coverage: Full Spectrum
03
Cycle Documentation

Integrated data logger and thermal printer outputs time, temperature, and pressure traces for every cycle. Provides compliant records for ISO 13485, GMP, and hospital CSSD accreditation

Audit Readiness: GMP Compliant
04
Multi-Layer Safety

Safety valve, door interlock system, over-temperature cutoff, and low-water alarm work in concert to prevent overpressure events. Door cannot open while chamber is pressurized

Safety Redundancy: 4-Layer System
05
Vertical Chamber Design

Top-loading vertical orientation accommodates tall flasks, IV bottles, bagged waste, and upright instrument trays that cannot fit in horizontal chamber formats without repackaging

Load Flexibility: Tall & Bagged Items
06
Stainless Steel Chamber

316L stainless steel inner chamber and basket resist corrosion from steam condensate and repeated thermal cycling — maintaining chamber integrity across thousands of sterilization cycles

Material Standard: 316L SS / ASME
Clinical & Laboratory Applications

Where vertical autoclaves are deployed across the life-sciences ecosystem

Hospital CSSD

Central Sterile Supply Departments use vertical autoclaves for routine instrument reprocessing — forceps, clamps, specula, and wrapped surgical packs requiring validated sterilization before reuse

Microbiology Laboratories

Culture media preparation, glassware sterilization, and biohazardous waste decontamination before disposal — critical for BSL-2 and BSL-3 containment laboratory safety protocols

Pharmaceutical Manufacturing

GMP-compliant sterilization of production equipment, stoppers, and fill-finish components. Cycle records feed directly into batch documentation for regulatory submission

Research Institutions

Autoclave use in animal research facilities for bedding, caging, and feed sterilization — and in cell culture labs for media, pipettes, and consumables requiring endotoxin-free conditions

Biosafety Waste Management

On-site decontamination of Category B infectious waste before municipal disposal — reducing transport risk and eliminating reliance on third-party waste contractors for routine loads

Dental & Veterinary Clinics

Compact vertical autoclave format suits point-of-care settings requiring validated handpiece, instrument, and cassette sterilization between procedures per infection control standards

Sterilization Validation Pipeline

From installation to ongoing compliance — how autoclave validation works in regulated environments

IQ — Installation Qualification
Verify autoclave installed per manufacturer specifications: utilities, chamber dimensions, safety device calibration
OQ — Operational Qualification
Empty chamber mapping with thermocouples confirms temperature uniformity at ±1°C across all chamber zones
PQ — Performance Qualification
Loaded chamber mapping + biological indicator (Geobacillus stearothermophilus) confirms kill at worst-case positions
Ongoing Monitoring
Routine BI testing, chemical indicators, Bowie-Dick test (pre-vac), and annual requalification per ISO 17665
Regulatory Basis: Validation protocols follow ISO 17665-1 (moist heat sterilization of health care products), ISO 11135 (medical devices), and EN 13060 / HTM 01-01 for healthcare steam sterilizers.
Technical Specifications
ParameterSpecificationStandard / Compliance
Chamber OrientationVertical (top-loading)ISO 17665-1
Temperature Range105°C – 134°C (±1°C accuracy)EN 13060
Operating PressureUp to 220 kPa (32 PSI)ASME BPVC VIII
Cycle ModesGravity displacement, Pre-vacuum, Liquid, WasteISO 11135
Control SystemDigital PLC with LCD displayIEC 61010-1
Chamber Material316L Stainless SteelASTM A240
Safety DevicesSafety valve, door interlock, over-temp cutoff, low-water alarmEN ISO 11607
DocumentationIntegrated data logger + thermal cycle printerISO 13485
Sterility AssuranceSAL 10⁻⁶EN 556-1
Validation ProtocolIQ / OQ / PQ compatibleISO 17665-1
Power Supply220–240V / 50–60HzIEC 62133
Deployment Environments
Hospitals & Clinics

CSSD, operating theatres, endoscopy units, dental surgeries requiring validated instrument reprocessing

Research Laboratories

BSL-2/3 labs, cell culture facilities, and animal research units needing media and waste autoclave cycles

Pharma & Biotech

GMP-compliant sterilization of equipment and components with full batch record documentation for regulatory audits

Veterinary & Ag Labs

Instrument sterilization, bedding processing, and necropsy waste decontamination in veterinary and agricultural research settings

Frequently Asked Questions

Gravity displacement cycles remove air by relying on steam entering from the top of the chamber and displacing the cooler, denser air downward and out through a drain. This method works well for non-porous loads — glassware, culture media, unwrapped instruments, and liquid loads. Pre-vacuum cycles use one or more vacuum pulses to actively evacuate air from the chamber and load before steam admission. This is required for porous loads (wrapped textiles, gowns), hollow instruments (tubing, handpieces), and any load where air pockets would prevent steam contact with surfaces.

Autoclave validation follows a three-stage protocol per ISO 17665-1: Installation Qualification (IQ) confirms the instrument is installed correctly with calibrated utilities; Operational Qualification (OQ) involves empty-chamber temperature mapping using calibrated thermocouples to confirm ±1°C uniformity; Performance Qualification (PQ) maps loaded chamber conditions and uses biological indicators (Geobacillus stearothermophilus spore strips at 10⁶ CFU) placed at worst-case locations. All three stages must be documented and approved before the autoclave is placed in routine use for sterile product or medical device processing.

Biological indicators (BI) using Geobacillus stearothermophilus spores (10⁶ CFU) are the primary monitoring tool — after exposure, the BI is incubated at 56°C for 48–72 hours; no growth confirms adequate lethality. Chemical indicators provide immediate visual confirmation: Class 1 (process indicators on packaging), Class 4 (multi-variable indicators for each load), and Class 5 (integrating indicators that respond to all critical parameters). For pre-vacuum cycles, the Bowie-Dick test is performed daily on an empty chamber to confirm air removal efficacy before loading patient-contact items.

Vertical autoclaves are top-loading, allowing upright placement of tall Erlenmeyer flasks, Schott bottles, graduated cylinders, and bagged infectious waste without requiring items to be laid on their side. This prevents spillage of liquid media during loading and ensures waste bags remain sealed in their intended orientation. For laboratories preparing large volumes of culture media or processing tall equipment, vertical geometry eliminates the repackaging step required when using horizontal floor-standing autoclaves, reducing preparation time and handling risk.

Routine maintenance includes daily tasks: check water level (use distilled or deionized water only), inspect door gasket for cracking or deformation, verify safety valve function, and review previous cycle printouts. Weekly: clean chamber interior with appropriate stainless steel cleaner, check drain filter and strainer for debris, and inspect chamber basket. Annually: calibrate temperature and pressure sensors against traceable standards, replace door gasket, service safety valve, and perform full IQ/OQ requalification if chamber conditions have changed. Records of all maintenance should be maintained in the equipment logbook for regulatory inspection.

No. Autoclaves are limited to heat- and moisture-stable materials. Items that cannot be autoclaved include: electrical devices and electronics, heat-sensitive plastics (check compatibility — polypropylene is generally safe; polystyrene is not), anhydrous powders and oils (steam cannot penetrate), sharp edges that damage packaging under steam conditions, and materials that degrade at 121°C or above. For heat-sensitive items, alternative sterilization methods include ethylene oxide (EO) gas, hydrogen peroxide plasma (VPHP), radiation (gamma or e-beam), or liquid chemical sterilants — each with specific applications, regulatory requirements, and cycle validation protocols.

Equip Your Laboratory with Validated Steam Sterilization

Explore the Fison Vertical Autoclave — built for cycle accuracy, safety compliance, and continuous laboratory operation.

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