WFI & Technical Water Systems
Complete pharmaceutical water system services including WFI generation, purified water distribution, passivation, sanitization, rouge prevention, and GMP-compliant validation. USP <643>, <645>, <1231> expertise.
Pharmaceutical Water Types & Specifications
Select a water type to view detailed specifications, applications, and quality requirements per USP standards.
Water for Injection
WFI — Highest Purity GradeUltra-pure water for preparation of parenterals, injectables, and sterile products. Must be generated by distillation or reverse osmosis with acceptable filtration. Requires hot storage (80°C) or validated cold storage with ozone/UV sanitization.
Common Applications
- Injectable drug formulation
- Final rinse for product-contact equipment
- API manufacturing processes
- Sterile product preparation
- Equipment cleaning final rinse
WFI Quality Specifications
Per USP <643>, <645>, <1231>Purified Water
PW — General Pharmaceutical UseHigh-purity water for non-parenteral preparations, equipment cleaning, API synthesis, and general pharmaceutical manufacturing. Generated by deionization, RO, or distillation. No endotoxin requirement but microbial control is essential.
Common Applications
- Oral dosage form manufacturing
- Topical product formulation
- Equipment and facility cleaning
- Chemical reagent preparation
- Laboratory operations
Purified Water Specifications
Per USP <643>, <645>Clean Steam
CS — Sterilization GradeSteam generated from WFI-quality feed water or produced to meet WFI quality when condensed. Used for sterilization-in-place (SIP) of product contact surfaces, autoclaving, and humidification in controlled environments.
Common Applications
- Sterilization-in-Place (SIP)
- Autoclave sterilization
- Product contact surface sterilization
- Clean room humidification
- Lyophilizer sterilization
Clean Steam Specifications
Per HTM 2010 / EN 285Water System Commissioning Process
Our validated 11-step process ensures pharmaceutical water systems meet USP specifications and GMP requirements from day one.
Gross Leak Check
Pressure test all connections, welds, and joints to verify system integrity before introducing any chemicals or water.
Alkaline Clean
Remove oils, greases, fabrication debris, and organic contamination using heated caustic solution circulation at 140-160°F.
Neutralize & Rinse
Neutralize alkaline residues and flush system with high-purity water to baseline conductivity and pH levels.
High-Velocity Flush
Achieve 5-10 ft/sec turbulent flow throughout distribution loop with inline filtration to remove particulate contamination.
Citric Acid Passivation
4-10% citric acid at 140-160°F for 2-4 hours removes free iron and establishes protective chromium oxide layer per ASTM A967.
Neutralize
Alkaline neutralization to pH 7-9 ensures complete acid removal and prepares surface for final rinsing.
Final Rinse
WFI or DI water rinse to conductivity <1.1 µS/cm, pH 6.5-7.5 stable, TOC <500 ppb meeting USP specifications.
Verification Testing
Ferroxyl test, water break test, visual inspection, conductivity, pH, and particle counts confirm passivation success.
System Dry
Complete drainage and nitrogen or filtered air purge to -40°F dewpoint prevents corrosion and biofilm formation.
Documentation Package
GMP-compliant batch records, verification testing, certificates of compliance, and IQ/OQ support documentation.
System Turnover
Final walkthrough, documentation review, and handoff to operations team with maintenance recommendations.
Contamination Risks & Prevention
Understanding contamination sources and implementing preventive measures is critical for maintaining pharmaceutical water quality.
Biofilm Formation
Bacterial biofilm develops when velocity drops below turbulent threshold, temperature falls <70°C, or systems stagnate. Biofilm harbors bacteria and sheds endotoxins.
Prevention Methods →Rouge Contamination
Iron oxide forms from incomplete passivation, aggressive CIP chemistry, or heat exposure. Rouge sheds particles and elevates iron content.
Derouging Services →Dead Leg Stagnation
Piping branches >6× diameter create stagnant zones with temperature stratification and accumulated contaminants. Primary site for bioburden excursions.
Flushing Services →Vent Filter Failure
Failed 0.2µm hydrophobic vent filters allow airborne contamination into storage tanks. Wet filters lose integrity and permit microbial ingress.
Learn More →Chemical Carryover
Inadequate rinsing after CIP leaves sanitizer residues that elevate conductivity, TOC, and pH. Minimum 3× system volume rinse required.
CIP Services →Maintenance Contamination
Component replacement introduces contamination without proper aseptic technique. Steam sterilization and validated procedures prevent issues.
GMP Services →Monitoring, Testing & Validation
Comprehensive testing programs ensure continuous compliance with USP specifications and early detection of quality degradation.
Conductivity
Continuous online measurement. Alert <1.1 µS/cm, action limit 1.3 µS/cm per USP <645>.
TOC Testing
Total Organic Carbon measured hourly. Alert >400 ppb, action limit 500 ppb per USP <643>.
Bioburden
Weekly membrane filtration testing. Alert 50 CFU/100mL, action 75 CFU/100mL for WFI.
Endotoxin
Weekly LAL or rFC testing. Alert >0.15 EU/mL, action limit 0.25 EU/mL for WFI.
Temperature
Continuous monitoring in hot storage (80°C ± 5°C) and distribution (>70°C).
Heavy Metals
Quarterly ICP-MS analysis per USP <643> monitoring lead, cadmium, arsenic, mercury.
pH Monitoring
Daily measurement at generation and key points. Specification 5.0-7.0 per USP <791>.
Anion Analysis
Monthly ion chromatography for chlorides (<0.5 ppm), sulfates, nitrates.
USP Water Specification Matrix
Comprehensive quality attributes and acceptance criteria per USP <643>, <645>, <1231> for pharmaceutical water systems.
| Test Parameter | WFI Limit | PW Limit | Test Method | Frequency |
|---|---|---|---|---|
| Conductivity @ 25°C | <1.3 µS/cm | <1.3 µS/cm | USP <645> Stage 1 | Continuous |
| Total Organic Carbon | <500 ppb | <500 ppb | USP <643> | Daily |
| Bioburden (Aerobic) | <10 CFU/100mL | <100 CFU/mL | Membrane Filtration | Weekly |
| Bacterial Endotoxin | <0.25 EU/mL | Not Required | LAL or rFC | Weekly |
| pH @ 25°C | 5.0 - 7.0 | 5.0 - 7.0 | USP <791> | Daily |
| Nitrate (NO₃⁻) | <0.2 ppm | <0.2 ppm | Ion Chromatography | Monthly |
| Heavy Metals | USP <643> limits | USP <643> limits | ICP-MS | Quarterly |
| Chlorides (Cl⁻) | <0.5 ppm | <0.5 ppm | Ion Chromatography | Monthly |
| Sulfates (SO₄²⁻) | <1 ppm | <1 ppm | Ion Chromatography | Monthly |
| Ammonia (NH₃) | <0.3 ppm | <0.3 ppm | Colorimetry | Monthly |
Technical Water System Questions
Common questions about WFI systems, passivation, sanitization, and GMP compliance.
Why is passivation required for WFI systems?
Passivation is critical for WFI systems because it removes free iron from stainless steel surfaces and establishes a protective chromium oxide layer. Without proper passivation, free iron oxidizes to form rouge, which sheds particles into the water, elevates iron content above USP limits, and creates rough surfaces that harbor biofilm.
For pharmaceutical water systems, we use citric acid passivation per ASTM A967 because it's safer to handle than nitric acid, produces equivalent results, and generates less hazardous waste. The process removes embedded iron from welding, fabrication, and installation while leaving chromium intact to form the passive layer.
- Prevents rouge formation and particle shedding
- Maintains iron content below USP <643> limits
- Creates smooth, cleanable surfaces
- Supports bioburden and endotoxin control
Hot vs. cold WFI storage - which is better?
Hot storage at 80°C ± 5°C is the industry standard and preferred method for WFI preservation. Continuous elevated temperature prevents microbial proliferation without requiring chemical sanitization agents, provides consistent quality at all use points, and simplifies validation.
Cold storage with ozone or UV sanitization is an alternative that reduces energy consumption but increases validation complexity. Cold systems require more frequent bioburden monitoring, validated sanitization cycles, and careful dead leg management. For new installations, hot storage is recommended unless specific process requirements mandate cold WFI.
What causes rouge and how is it removed?
Rouge is iron oxide contamination that forms on stainless steel surfaces in water and steam systems. Common causes include incomplete passivation during commissioning, aggressive CIP chemistry with high chloride content, heat exposure during SIP cycles, and carbon steel contamination from tools or external sources.
Our derouging services use EDTA or citric acid formulations to dissolve rouge deposits, followed by re-passivation to restore the protective chromium oxide layer. The process includes visual inspection documentation, before/after iron testing, and complete GMP documentation for FDA inspections.
What documentation do you provide for validation?
CXP provides comprehensive GMP-compliant documentation supporting IQ/OQ validation protocols. Our documentation packages include executed batch records with all process parameters, verification testing results (ferroxyl, conductivity, pH, particle counts), passivation certificates of compliance, before/after photographic documentation, and deviation reports if applicable.
All documentation meets FDA 21 CFR Part 211 requirements and supports regulatory inspections. We can provide documentation in client-specific formats and integrate with your quality management systems. Contact us for a sample documentation package.
How fast can you respond to urgent projects?
Our emergency response services provide rapid mobilization for urgent pharmaceutical water system needs. With mobile CIP/passivation equipment and pre-staged chemicals, we can typically mobilize within 24-48 hours for critical situations.
Emergency scenarios we support include post-installation rush commissioning, bioburden excursion recovery, rouge remediation before FDA inspection, and system repair re-qualification. Contact us at (919) 283-1023 for emergency availability.
CXP Water System Services
End-to-end support for WFI, purified water, and clean steam systems from commissioning through ongoing maintenance.
New System Passivation
Complete passivation of new WFI and PW systems per ASTM A967 with citric acid circulation, ferroxyl verification, and GMP documentation.
Learn More →Derouging Services
EDTA and citric acid derouging removes rouge contamination, restores electropolished surfaces, and re-passivates per ASTM A967.
Learn More →High-Velocity Flushing
Pre-passivation flushing removes construction debris using mobile CIP units achieving 5-10 ft/sec turbulent flow with filtration.
Learn More →Thermal Sanitization
Clean steam SIP procedures achieving 121-132°C for 30-60 minutes with biological indicator validation confirming 6-log reduction.
Learn More →Water Quality Testing
Comprehensive testing including conductivity, TOC, bioburden, endotoxin, heavy metals, and anion analysis supporting validation.
Learn More →IQ/OQ Documentation
GMP-compliant documentation packages including protocols, executed records, verification testing, and validation summaries.
Request Quote →Explore More Services & Guides
Passivation Services
Cleaning Services
Technical Guides
Need WFI or Technical Water System Services?
CXP Solutions provides complete pharmaceutical water system support including passivation, derouging, sanitization, validation, and ongoing maintenance. USP <643>, <645>, <1231> expertise with GMP-compliant documentation supporting FDA and international regulatory inspections.
Related Services: Pharmaceutical Passivation | Derouging Services | Industrial Cleaning | Data Center Cooling