Technology Foundation

Sterilization Science

Non-ionizing methodology derived from regulated biological processing.

The Technology

Vaporized hydrogen peroxide delivered under extreme vacuum enables vapor-phase diffusion throughout complex biological material—penetrating beyond surface boundaries into the material matrix.

The controlled vacuum chamber environment ensures consistent distribution and contact. Validated parameters govern exposure duration, concentration, and environmental conditions—producing repeatable, documented outcomes.

Post-process decomposition is complete and chemically irreversible: VHP breaks down entirely to H₂O and O₂—water vapor and oxygen. Zero chemical residue. Zero molecular damage. This is not a trace-level outcome; it is the inherent end-state of the chemistry, and it is why pharmaceutical-grade application is viable.

What It Is Not

—Ionizing radiation

—Ozone-based processing

—Thermal sterilization

—Ambient fogging or misting

—Surface-only decontamination

What It Is

—Controlled vacuum sterilization

—Vapor-phase diffusion process

—Deep penetrative exposure

—Low-temperature compatible

—Decades of validated application

Foundation

Non-Ionizing Process

Microbial disruption without ionizing energy—material chemistry remains unaltered by the process.

Preservation

Material Integrity

Selective action—parameters that microorganisms cannot tolerate but sensitive compounds can.

Validation

Documented Efficacy

Log reduction measured against scientific standards. Repeatable parameters. Consistent outcomes.

Why Non-Ionizing Matters

Ionizing Radiation

Gamma rays, X-rays, and electron beams carry enough energy to break molecular bonds indiscriminately. Effective for sterilization, but can alter material chemistry in unintended ways.

Vacuum-Enabled VHP

VHP delivered under extreme vacuum achieves microbial disruption through deep vapor-phase diffusion—without the penetrating energy that can alter material chemistry. Molecular structure remains intact.

Method Comparison

Not all sterilization methods are equivalent. These distinctions matter at the regulatory level.

Attribute	TheBOX® (VHP)	Ionizing Radiation	Ozone	Traditional Remediation
Pharma heritage	FDA-regulated sterilization	Industrial sterilization	Industrial / water treatment	None
FDA Established Category A	Yes (January 2024)	Yes (legacy)	No (Category B)	No
Standards-based self-validation	ISO 22441:2022	ISO 11137 (facility not operator-accessible)	No recognized standard	No validation pathway
Residuals	Zero (H₂O + O₂)	None, but molecular damage	Ozone residuals possible	Chemical residuals
Molecular integrity	Preserved	Compromised (bond-breaking)	Surface-only treatment	Variable
Audit documentation	Built-in, lot-level	Batch-level at best	Minimal	Typically none
Schedule III pathway	Direct (pharma-grade)	Partial	Unlikely	Not applicable

Selective Action

Microorganisms and plant-derived compounds respond differently to this process. System design exploits this differential susceptibility.

Differential Susceptibility

Microbial structures are vulnerable at concentrations and durations that do not significantly impact cannabinoid or terpene chemistry. This selectivity is the basis of process design.

Parameter Control

• Exposure duration: Managed to achieve efficacy without excess

• Concentration: Maintained within validated range

• Environment: Temperature, humidity, and pressure regulated

Scientific Background

Established Use

Vaporized hydrogen peroxide has been recognized as a sterilant for nearly five decades — from its 1979 patent as a cold sterilization alternative from ethylene oxide, through its first FDA clearance for medical device sterilization in 1993, to its formal designation as an Established Category A method in January 2024. It is not a technology adapted from pharmaceutical applications — it is a pharmaceutical technology, one that has governed sterilization in the most demanding regulated environments on earth. The technology behind TheBOX® draws on this lineage through PuroGen's 22+ years of operating VHP within FDA-regulated biological processing — specifically, the sterilization of human allograft tissue for surgical implantation. ISO 14937, ISO 22441, and ISO 10993 compliance frameworks were built around it. The Category A designation also established ISO 22441:2022 as an FDA-recognized consensus standard — providing a published, internationally accepted framework for process validation that operators can validate against directly, rather than building and defending proprietary protocols from scratch.

• Medical device sterilization: Electronics, polymers, optical components, sensors, and battery-containing devices that cannot tolerate thermal or ionizing methods

• Human tissue processing: Allograft tissue prepared for clinical transplantation under FDA oversight, where irradiation or heat would compromise biological structure and osteoinductive function

• Pharmaceutical manufacturing: Cleanroom and isolator decontamination in environments requiring validated sterility without residue—the standard against which all others are measured

• Hospital environments: Operating suites, patient rooms, and critical care areas where rapid turnaround and material compatibility are required

When the most delicate sterilization challenges arise—across healthcare, pharmaceutical, and advanced manufacturing—VHP is the established methodology of record. TheBOX® brings that same lineage to cannabis.

Cannabis Application

Cannabis presented a constraint-driven engineering problem. Dried flower is a moisture-bearing, chemically volatile botanical material—conditions that commercially available VHP systems are not designed to accommodate. Standard VHP equipment will not initiate in the presence of meaningful residual moisture and lacks the programmability required to adapt to moisture-bearing biological loads.

The core technology was originally developed by PuroGen, the parent company, for human tissue sterilization in the transplant industry. Human allograft tissue presented similar preservation constraints: moisture sensitivity and the requirement to preserve osteoinductivity and osteoconductivity—biological properties essential to surgical outcomes.

The parallel between preserving biological performance in tissue and preserving terpenes, cannabinoids, and moisture behavior in cannabis informed the engineering approach. TheBOX® was purpose-engineered to operate in moisture-bearing biological materials using controlled vapor-phase diffusion under extreme vacuum—achieving microbial elimination alongside preservation, not at the expense of it.

Adaptation of this technology to cannabis began in 2015. More than 100 units have since been deployed across U.S. and international markets.

Technology Lineage

Nearly five decades of VHP sterilization science. More than two decades of PuroGen operating within it.

VHP Technology Class

PuroGen / TheBOX®

1975

Patent application filed

Hydrogen peroxide vapor sterilization — Moore & Perkinson

1975

Patent application filed

Hydrogen peroxide vapor sterilization — Moore & Perkinson

1979

US Patent #4,169,123 granted

Cold sterilization alternative to ethylene oxide and radiation

1979

US Patent #4,169,123 granted

Cold sterilization alternative to ethylene oxide and radiation

1991

STERIS launches VHP 1000 commercially

First broad pharmaceutical deployment of VHP technology

1991

STERIS launches VHP 1000 commercially

First broad pharmaceutical deployment of VHP technology

1993

First FDA clearance: STERRAD 100

Advanced Sterilization Products / J&J — medical device sterilization

1993

First FDA clearance: STERRAD 100

Advanced Sterilization Products / J&J — medical device sterilization

2002

FDA formalizes VHP in aseptic guidance

FDA addresses VHP isolator decontamination in revised aseptic processing guidance

2002

FDA formalizes VHP in aseptic guidance

FDA addresses VHP isolator decontamination in revised aseptic processing guidance

2003

PuroGen begins FDA-regulated VHP operations

Human allograft tissue sterilization for surgical transplantation under FDA oversight

2003

PuroGen begins FDA-regulated VHP operations

Human allograft tissue sterilization for surgical transplantation under FDA oversight

2015

TheBOX® development begins

PuroGen adapts VHP technology for dried cannabis flower

2015

TheBOX® development begins

PuroGen adapts VHP technology for dried cannabis flower

2022

ISO 22441:2022 published

First international VHP sterilization standard

2022

ISO 22441:2022 published

First international VHP sterilization standard

2024

FDA Established Category A designation

FDA designates VHP as Established Category A; recognizes ISO 22441:2022

2024

FDA Established Category A designation

FDA designates VHP as Established Category A; recognizes ISO 22441:2022

2024

TheBOX® surpasses 100 deployed units

U.S. and international cannabis markets

2024

TheBOX® surpasses 100 deployed units

U.S. and international cannabis markets

The FDA's 2024 Category A designation did not just validate VHP's history — it published the framework for companies to validate their own VHP processes. By recognizing ISO 22441:2022 as the governing consensus standard, the FDA established a standards-based self-validation pathway: defined acceptance criteria, established methodology, documented routine control. For cannabis operators who must self-validate because FDA-certified facilities cannot handle THC-containing products, this distinction is structural. It is the difference between defending a proprietary process to every auditor who encounters it and demonstrating compliance with a framework that auditors already recognize.

FDA Sterilization Classification

The FDA categorizes sterilization methods into three tiers based on regulatory history, published evidence, and recognized consensus standards. Classification determines the validation burden, documentation requirements, and regulatory scrutiny applied to each method.

Established Category A

Methods with a long history of safe and effective use, validated by multiple sources including FDA clearance and FDA-recognized consensus standards.

Validation Burden

Reference the recognized consensus standard. Demonstrate compliance. Reduced documentation requirements.

Recognized Standard

Published, internationally accepted, FDA-acknowledged.

Self-Validation Pathway

Operators validate against a published framework with defined acceptance criteria. Auditable by any competent authority.

Examples

Moist heat, Dry heat, Ethylene oxide (EtO), Radiation, VHP (as of January 2024)

TheBOX® operates within this technology class

Established Category B

Methods with some published evidence of safety and effectiveness, but no FDA-recognized dedicated consensus standard.

Validation Burden

Must provide more extensive custom validation data. No consensus standard to reference.

Recognized Standard

None recognized by FDA.

Self-Validation Pathway

Proprietary validation protocols. Must be independently evaluated by each authority that encounters them.

Examples

Ozone sterilization, Flexible bag systems

Ozone-based cannabis methods fall here

Novel

Methods supported by little or no published information, history of FDA assessment, or consensus standards related to the modality.

Validation Burden

Highest burden. Full custom validation from scratch. Extensive documentation required.

Recognized Standard

None.

Self-Validation Pathway

No established framework. Every aspect of the validation methodology itself must be defended.

Examples

Emerging or proprietary sterilization technologies

Traditional remediation has no FDA sterilization classification

Attribute	Category A	Category B	Novel
FDA-recognized consensus standard	Yes	No	No
Validation approach	Reference standard	Custom validation	Full custom from scratch
Documentation burden	Reduced (standard-based)	Moderate (evidence-based)	Highest (novel justification)
Regulatory defensibility	Strongest — standard is known	Moderate — methodology must be evaluated	Weakest — everything must be justified

Cannabis Method Mapping

Cannabis Method	FDA Tier	Recognized Standard	Self-Validation Framework
VHP / TheBOX®	Established Category A	ISO 22441:2022	Standards-based: validate against published framework
Ozone	Established Category B	None (FDA-recognized)	Proprietary: custom protocol, no standard reference
Ionizing Radiation	Established Category A	Multiple (ISO 11137)	Standards-based — facility not operator-accessible for cannabis
Traditional Remediation	Not classified	None	No standardized validation pathway exists

Source: FDA Final Guidance, “Submission and Review of Sterility Information in Premarket Notification (510(k)) Submissions for Devices Labeled as Sterile,” Revised January 2024

Why This Matters for Cannabis Adoption

Cannabis operators cannot access traditional FDA-certified validation facilities — THC-containing products are prohibited from entering those facilities under current federal law. Self-validation is not a choice; it is a structural requirement of the industry.

When a company adopts a sterilization technology, the question regulators will ask is: how did you validate your process? The answer depends entirely on the FDA classification of the method used.

For Established Category A methods like VHP, validation is conducted against ISO 22441:2022 — a published, FDA-recognized consensus standard with defined acceptance criteria and established methodology. The validation is auditable by any competent authority, portable across regulatory jurisdictions, and defensible under federal scrutiny.

For Category B methods like ozone, no FDA-recognized standard exists. Validation protocols are proprietary and must be independently evaluated by every authority that encounters them. For unclassified methods, no standardized validation pathway exists at all.

The FDA's 2024 reclassification of VHP did not just recognize a technology — it gave every company adopting that technology a framework to validate and defend their own processes.

Reactive Oxygen^®

Reactive Oxygen® is the branded name for the proprietary reagent and process framework integrated within TheBOX® system. It does not refer to uncontrolled reactive oxygen species and should not be interpreted as free-radical chemistry.

Within the Reactive Oxygen® framework, reactive activity is intentionally generated, transient, and spatially constrained—a function of defined process conditions rather than ambient chemical behavior. Microbial control is system-mediated: governed by chamber architecture, parameter control, and exposure boundaries—not by chemical aggressiveness alone. The extreme vacuum conditions also function as a preventative mechanism: by removing atmospheric oxygen and collapsing the physical environment that supports microbial respiration and colonization, the chamber creates conditions hostile to microbial survival before oxidative activity begins. Prevention and elimination are simultaneous, not sequential.

VHP undergoes complete decomposition at the close of every cycle—breaking down entirely into water vapor (H₂O) and oxygen (O₂). No chemical byproducts. No residual compounds on processed material. This is not a performance claim; it is the known end-state of the chemistry, independently verifiable, and the reason zero-residual sterilization is achievable at all.

The result is predictable, repeatable sterilization outcomes with material preservation as a design constraint, not a trade-off.

Non-ionizing

No material-altering radiation

VHP-based

Controlled reagent delivery

Zero residuals

Decomposes completely to H₂O + O₂ — no chemical trace

Deep diffusion

Vacuum-enabled penetration

Material preservation

Compound integrity maintained

System-mediated

Architecture-governed outcomes

Validation Philosophy

Demonstrating that a process consistently produces intended outcomes under defined conditions.

Log Reduction

Microbial reduction expressed in logarithmic terms—1-log represents 90% decrease; 3-log represents 99.9%. A scientific convention for standardized comparison.

Repeatability

Process parameters controlled with sufficient precision that the same inputs yield the same results across cycles, units, and facilities.

Documentation

Cycle parameters, lot identification, and process conditions captured and retained—the foundation of defensible claims about outcomes.

Consistency

System design, automation, and operator controls that translate validated parameters to real-world consistency.

Scope of Validation

Documented evidence across system efficacy, safety, and operational constraints.

System Efficacy

Biological Indicator Validation

—Industry-standard biological indicators

—Empty chamber testing (material-independent)

—~1,000,000 CFU (~6-log) reduction per cycle

—Demonstrates system capability

Internal Field Testing

—Internal plating within licensed operations

—Observed reductions: ~450,000 to 1,000,000 CFU

—Operational confirmation, not lab certification

—Material-dependent outcomes expected

Regulatory Testing Constraints

THC-containing cannabis cannot be sent to most accredited microbiology institutions. Controlled substance handling restrictions limit conventional third-party validation pathways. This structural constraint applies industry-wide and is not unique to any single manufacturer or system.

Material Variability

What Varies

—Flower density, porosity, internal structure

—Diffusion-dependent behavior in vapor-phase processes

—Heterogeneous biological material

What Does Not Vary

—System capability is constant

—Process parameters are governed

—Observed outcomes reflect material properties

Safety Validation

Human & Environmental

No residual compounds; decomposes to water and oxygen

Product Safety

Material integrity preserved; no ionizing energy

Biological Safety

Process does not alter molecular chemistry

Declared Validations

Third-party studies conducted under recognized standards and protocols.

Reactive Oxygen® Environmental Safety — Hydrogen Peroxide Vapor Monitoring

Independent third-party environmental monitoring by SGS Galson (ISO/IEC 17025 accredited)

Independent third-party environmental monitoring of hydrogen peroxide vapor concentration during and after system operation was conducted to validate that vapor levels in areas surrounding the system remain within established occupational exposure limits during normal operation.

Passive air monitoring badges were deployed at multiple operator and facility locations during active system use. Samples were collected under real operating conditions and analyzed using ACS SOP II-99 based on OSHA Method 1019. Exposure was evaluated on an 8-hour time-weighted average basis.

Measured concentrations ranged from less than 0.03 ppm to 0.06 ppm. All recorded values remained well below OSHA's permissible exposure limit of 1.0 ppm based on an 8-hour time-weighted average. No short-term exposure exceedances were observed.

Environmental hydrogen peroxide vapor levels associated with system operation remained orders of magnitude below established occupational exposure limits, confirming controlled containment and exhaust performance under real operating conditions.

—Study type: Independent third-party environmental monitoring
—Laboratory: SGS Galson (ISO/IEC 17025 accredited)
—Analytical support: Advanced Chemical Sensors
—Method: ACS SOP II-99 based on OSHA Method 1019
—Exposure basis: 8-hour time-weighted average
—Measured parameter: Hydrogen peroxide vapor concentration (ppm)
—Sampling locations: Box operator position, inside chamber door, between system units, facility perimeter
—Measured range: <0.03 ppm to 0.06 ppm
—OSHA permissible exposure limit: 1.0 ppm (8-hour TWA)
—Analytical limit of quantitation: 0.03 ppm (8-hour basis)

Role in System Validation

This study documents facility-level environmental control and confirms that purification is achieved without uncontrolled atmospheric release, reinforcing the system as a closed, governed process control infrastructure rather than an ambient treatment method.

Full monitoring reports, sampling data, and laboratory analysis are maintained under documentation control and are available for compliance or regulatory review subject to confidentiality agreements.

TheBOX® Installation & Operational Qualification (IQ/OQ) — Internal Process Validation

Controlled internal validation protocols documenting system installation and operational execution

Installation Qualification (IQ) and Operational Qualification (OQ) were executed under controlled internal validation protocols to document that the system was installed correctly, configured according to specification, and operates consistently within defined parameters under intended operating conditions.

IQ/OQ activities were executed using a predefined protocol (VAL-051-IQ/OQ, Revision 1) and approved acceptance criteria. Verification steps included physical inspection, component verification, utility checks, calibration review, operational testing, and documented cycle execution. All activities were recorded contemporaneously and reviewed against protocol-defined requirements.

Multiple programmed cycles were executed to confirm correct system initialization and sequencing, controlled vacuum, injection, diffusion, and cleaning stages, repeatable timing and pressure profiles, proper alarm handling and cycle completion logic, and accurate generation of cycle records and reports.

The system met all installation and operational qualification requirements. No unresolved deviations were recorded during protocol execution. Validation was completed with a documented PASS outcome.

—Validation type: Installation Qualification (IQ) and Operational Qualification (OQ)
—Validation reference: Protocol VAL-051-IQ/OQ, Revision 1
—Scope — Installation: Equipment installation, configuration verification, utility/power/component conformity, calibration status of critical instruments
—Scope — Operational: Operational sequence execution, cycle parameter consistency and control, documentation/training/procedural compliance
—Operational verification: System initialization, vacuum/injection/diffusion/cleaning stages, timing/pressure profiles, alarm handling, cycle records
—Acceptance criteria: Predefined acceptance criteria specified in IQ/OQ protocol
—Result: PASS — All requirements met, no unresolved deviations

Role in System Validation

This IQ/OQ validation establishes internal process discipline and execution integrity. It confirms that downstream validation, testing, and performance claims are built on a qualified operational foundation rather than assumptions or undocumented setup.

Installation and operational qualification confirmed that the system is installed correctly and operates in accordance with defined specifications and procedural controls, supporting its role as a governed, repeatable process platform.

Full validation protocols, execution records, and deviation logs are maintained under documentation control and are available for compliance or regulatory review subject to confidentiality agreements.

FDA VHP Classification — Established Category A

U.S. Food and Drug Administration, Final Guidance Revision, January 8, 2024

In January 2024, the FDA revised its final guidance on sterility information in premarket 510(k) submissions to designate vaporized hydrogen peroxide as an Established Category A sterilization method for medical devices.

Established Category A methods are those with a long-standing record of safe and effective use, including moist heat, dry heat, ethylene oxide, and radiation. VHP's addition to this category was accompanied by formal recognition of ISO 22441:2022 as the governing international standard.

This classification applies to VHP as a technology class — the same technology class from which TheBOX®'s Reactive Oxygen process framework is derived. The designation does not imply FDA approval of any cannabis application; it confirms VHP's established regulatory standing within the frameworks cannabis processing standards will reference as federal oversight evolves.

—Issuing body: U.S. Food and Drug Administration (FDA)
—Document: Submission and Review of Sterility Information in Premarket Notification (510(k)) Submissions for Devices Labeled as Sterile (Revised)
—Date: January 8, 2024
—Classification: Established Category A sterilization method
—Standard recognized: ISO 22441:2022 — Low temperature vaporized hydrogen peroxide: sterilization of medical devices

Significance for Self-Validating Operations

Established Category A classification means VHP sterilization processes can be validated against a published, FDA-recognized consensus standard (ISO 22441:2022) rather than requiring custom validation justified from first principles. For industries where operators must self-validate their sterilization processes — including cannabis, where FDA-certified validation facilities cannot handle THC-containing products — this distinction is operationally transformative. Standards-based self-validation is auditable, defensible, and portable across regulatory jurisdictions.

Methods classified as Established Category B (such as ozone) or unclassified (such as traditional remediation) do not have an FDA-recognized consensus standard. Operators using those methods must build and defend proprietary validation protocols independently with every regulatory authority that evaluates them.

Source: FDA.gov — Guidance Documents. Full guidance document publicly available at FDA.gov: 'Submission and Review of Sterility Information in Premarket Notification (510(k)) Submissions for Devices Labeled as Sterile,' Revised January 2024.

The process is validated. The parameters are documented. The outcomes are repeatable.

This is the scientific foundation. TheBOX® is the system that implements it for regulated cannabis operations.

Explore TheBOX®Contact Us

Process Control for Regulated Cannabis Operations