Pharmaceuticals

A pharmaceutical plant operates in conditions where any microbiological failure can directly affect batch release, validation status, and complaint risk. That is why ozone is usually considered part of a broader biosafety chain: from incoming transport and container handling to sanitary protection of purified water, clean rooms, and finished-goods storage.

It is important to define ozone's real role correctly. In most projects it is not used to replace every other sterilization method, but as a complementary tool for zones that benefit from penetrating gas treatment, low residue risk, biofilm control in water loops, and gentler processing of cotton or cellulose materials compared with chlorine-based approaches.

Where ozone is strongest: its best value is in sanitizing water and air systems, clean rooms, packaging, quarantine areas, and return logistics. For any specific facility, cycle parameters must always be validated against the product, room volume, material compatibility, and EHS/GMP requirements.

Key ozone tasks in a pharmaceutical facility

Sanitization of purified-water tanks, storage vessels, and distribution loops, including ambient WFI systems
Disinfection of clean rooms and HVAC outside working shifts, including hard-to-reach zones
Treatment of incoming containers, pallets, packaging areas, and product-contact-adjacent surfaces
Reduction of bioload and odor in quarantine rooms, warehouses, and return logistics
Bleaching and simultaneous disinfection of cotton, gauze, wool, and other cellulose-based materials
Oxidation of difficult organic contaminants and support for wastewater treatment

Technology chain: from gate to warehouse

When a plant is viewed as one GMP system, ozone fits naturally into several sequential points:

Transport and entry quarantine

Trucks, insulated vans, wheel zones, pallets, and return containers can pass through a dedicated gas or ozonated-water sanitation cycle before being allowed into cleaner production areas.

Incoming containers and packaging

Drums, canisters, intermediate containers, caps, secondary packaging, and process carts are treated before entering the manufacturing contour so dust, spores, and external microflora are not brought inside.

Purified water and distribution loops

Ozone is applied to protect cold water storage and distribution systems where biofilm control, lower microbial load, and less reliance on hot sanitization are critical.

Clean rooms, HVAC, and equipment

After a shift, empty rooms, ventilation branches, airlocks, chambers, and selected equipment can be placed into an ozone cycle followed by degassing and confirmation of a safe residual level.

Cotton, gauze, and cellulose materials

For medical cotton wool, dressings, and some packaging-related materials, ozone is attractive as a low-temperature gas-phase oxidant that can bleach and reduce microbial contamination at the same time.

Warehouse and finished-product release

Ozone is also used in quarantine rooms, return logistics, suspect-batch areas, cold rooms, and warehouses where odor control, mold prevention, and lower background microbiology matter between cycles.

Bleaching cotton and cellulose materials: ozone vs chlorine and peroxide

For medical cotton wool, gauze, bandages, and other cellulose-based materials, aqueous peroxide processes have long been the standard reference, while chlorine-based chemistries were used historically. Research into gas-phase ozone bleaching shows a lower-temperature process with simultaneous disinfection, which is especially relevant for medical-use materials.

Comparison of cotton bleaching and sanitation approaches
Parameter	Ozone	Chlorine / hypochlorite	Hydrogen peroxide
Process medium	Gas phase, low water consumption	Aqueous, chemically aggressive	Usually aqueous bath
Typical temperature mode	Around 35 °C	Often low, but with aggressive chemistry	Up to ~98 °C in the standard route
Residues after cycle	Decomposes to oxygen	Risk of chlorine-bearing residues and by-products	Requires residue control and rinsing
Impact on material	Gentle when the process is validated	Risk of damage and yellowing if the regime is wrong	Reliable, but more energy- and water-intensive
Additional effect	Bleaching plus biocidal action	Bleaching without residue advantages	Bleaching, sometimes with a separate disinfection step

For pharmaceutical materials, whiteness is only part of the requirement. Strength retention, microbiological purity, and process control matter just as much. The 2024 Materials study showed that gas-phase ozone-based schemes can combine bleaching and disinfection at 35 °C with minimal water use.

Drug transport and quarantine measures

In pharmaceuticals, logistics is not only about temperature and traceability. It is also about the sanitary status of vehicles, returnable packaging, and buffer rooms. Ozone is useful here as a barrier technology between batches and risk zones.

Treatment of vehicle bodies, wheel zones, pallets, and returnable containers before entry to the site
Sanitization of vans, containers, and cold-room spaces between supply cycles
Quarantine rooms for returns, suspect lots, or externally contaminated packaging
Degassing and verification of a safe residual level before personnel re-entry
Use together with normal washing, HEPA ventilation, and standard SOPs rather than as a replacement for the whole sanitation program

What is publicly known about industrial use

Public GMP case studies that disclose the pharmaceutical company name are limited because many projects are described anonymously by equipment suppliers. Even so, the open data is enough to show where ozone has already matured into accepted practice.

Public examples and industry signals
Organization / example	What has been implemented or published	Why it matters
Sterile manufacturer in Rancho Cucamonga (Xylem / Evoqua case)	Ozone disinfection for a purified-water system serving injectable, intranasal, and inhalation product lines	Reduced downtime, better parameter verification, and improved employee safety
ISPE Good Practice Guide, 2024	Second edition of the industry guide on ozone sanitization of pharmaceutical water storage and distribution systems	A clear sign that the technology has entered mature engineering and GMP practice
Novartis RLT / ISPE industry experts	Large-pharma experts participate in shaping best practices for ozone sanitization	This indirectly confirms serious interest from advanced pharma sites in ozone-based water-loop control
GMP solution suppliers: Xylem, Ozonia, Nuvonic, Mettler Toledo	Ozone generation, residual O3 control, monitoring, and integration into water loops and sanitization cycles	The technology is supported by a full industrial equipment ecosystem

Why pharmaceutical plants consider ozone

No chlorine chemistry in the process boundary

After the cycle, ozone decomposes to oxygen, which makes it attractive where chlorine-bearing residues and harsh chemical odors are undesirable.

Penetrating gas treatment

Ozone reaches ventilation branches, seams, voids, packaging gaps, and other areas that are difficult to sanitize fully with manual wiping alone.

Support for water systems

For purified water and ambient WFI, it offers a way to manage biofilm and microflora without depending only on hot sanitization.

Gentler work with cellulose materials

For materials such as cotton wool, gauze, and bandages, ozone offers an interesting combination of bleaching and disinfection in a milder temperature regime.