The quiet backbone of pharma: a no‑drama validation plan for clean steam and air

In pharmaceutical manufacturing, utility quality is governed internationally even when national GMPs align with global guidance. Although Indonesian GMP (CPOB) follows WHO/PIC/S guidelines, international standards primarily govern utility quality. ISO 8573‑1:2010 defines compressed air purity classes by particles, water, and oil (www.pharmtech.com), while the US Pharmacopeia recognizes “pure steam” similar to Water‑for‑Injection (WFI) quality (www.drugfuture.com).

In practice, clean steam condensate is tested to compendial water standards—conductivity ≤1.1 μS/cm at 20 °C and TOC ≤0.5 mg/L (www.pharmaguideline.co.uk)—and must meet stringent endotoxin limits (alert ≤0.125 EU/mL; action ≥0.25 EU/mL) (www.gmpsop.com). For compressed air, ISO 8573‑1 Class 1—often targeted in pharma—permits only trace particulates and oil (e.g., ≤10 particles ≥1 μm per m³ and ≤0.01 mg oil/m³) and typically requires a pressure dew point ≤–40 °C (www.atlascopco.com).

Regulatory guides emphasize risk‑based specifications: any air or steam contacting product must be “of appropriate chemical, particulate, and microbial quality” for its use (www.americanpharmaceuticalreview.com). Clean steam is generated from pretreated water (analogous to WFI pretreatment) to avoid carrying contaminants (www.drugfuture.com).

Steam system installation qualification (IQ)

IQ verifies the system is built to spec and GMP: correct materials (e.g., welded stainless steel piping), proper supports and insulation, sloped self‑draining piping, installed traps, vents, and blow‑downs, calibrated gauges and alarms, and complete documentation (P&IDs, material certificates, calibration certificates). Safety devices (pressure relief valves, steam traps) are verified against manufacturer specs, with special attention to eliminating hard bends or dead‑legs that trap condensate. Utilities (electrical, any air supply to control panels) and cleaning/sanitization circuits (if any) are confirmed present and compliant. IQ also covers component traceability and initial sanitization (e.g., steam sterilization of equipment).

Steam system operational qualification (OQ)

OQ exercises controls and performance: run the boiler/steam generator through full cycles, verify setpoints and alarms (pressure, temperature, water level), and calibrate sensors. For clean steam systems, confirm feedwater treatment functions—such as demineralization—are operational; many plants validate this unit operation explicitly as part of steam readiness (demineralizer). Measure steam dryness and superheat—using a pitot tube or steam quality tester—and ensure the steam leaving the generator is at most 2 °C superheated above the local boiling point. Check non‑condensable gas levels in condensate (e.g., ISO or USP methods) for initial compliance.

Functional tests of condensate drains and traps aim to prevent steam hammer or flooding; a representative protocol pressurizes the system and verifies each trap vents condensate at setpoints. OQ should also include a leak test and pressure‑drop checks across filters and dryers. An operational insight informs this rigor: leaks can waste 20–30% of a compressor’s output (and by analogy, untrapped condensate wastes steam energy) (pharmaceuticalmanufacturer.media).

Steam system performance qualification (PQ)

PQ demonstrates quality under routine use with multi‑day sampling of steam condensate at normal production flow and at every critical use location. One non‑condensable gas test collects condensate over a fixed time and measures liberated gases; acceptance is typically <~3–3.5% gas by volume relative to condensate—values ≲3.5% pass (www.pharmaguideline.co.uk). Dryness is measured by heat‑balance or a gravimetric method; an acceptable dryness fraction is usually ≥0.90 (90%), with an example spec of 0.90–0.95 (www.pharmaguideline.co.uk). Superheat is checked to confirm steam temperature remains close to saturation and not >2 °C above boiling at service points (www.pharmaguideline.co.uk).

Chemical and microbial tests analyze condensate against compendial water: conductivity ≤1.1 µS/cm at 20 °C (or 1.3 at 25 °C) and TOC ≤0.5 mg/L (www.pharmaguideline.co.uk). Microbial limits in the cited PQ example include total microbial count ≤10 CFU/100 mL and absence of E. coli, Staph. aureus, P. aeruginosa, or Salmonella, plus endotoxin <0.25 EU/mL (www.pharmaguideline.co.uk). Sampling points include the steam generator weekly and each critical use point at least monthly, rotating so every use point is checked at least every six months (www.gmpsop.com; www.pharmtech.com). Condensate samples for endotoxin are collected aseptically and tested promptly (www.gmpsop.com). PQ acceptance is “pass” for consecutive days—often 3 or more (www.pharmtech.com; www.pharmaguideline.co.uk).

Compressed air installation qualification (IQ)

IQ confirms the compressor, filters, dryers, and distribution piping are installed per specification. Teams verify compressor type (oil‑free vs. oil‑lubricated) and capacity, ensure filters and dryers are correctly sized/mounted with properly routed condensate drains, and confirm piping is stainless steel or conductive polymer to minimize particle shedding (www.pharmtech.com). Gauges, alarms (high/low pressure, high moisture), dew‑point or blowdown valves must be installed per design. As‑built documentation captures make/model/serial for all components and verifies utilities (coolant water, power) are connected and controlled. Facilities often specify point‑of‑use sterile filtration in stainless housings; pharma‑grade housings align with IQ expectations (stainless cartridge housing).

Compressed air operational qualification (OQ)

OQ runs systems through start/stop cycles, control logic (including lead/lag or backup units), and safety devices. Teams measure steady‑state pressure and flow under load, calibrate dew‑point sensors or hygrometers, and confirm dryers achieve the design dew point (<–20 or –40 °C, depending on specification). Pressure drop across each filter is measured to verify clean/dirty differential, with OEM filter changes used to validate gauge triggers. All sensors (pressure, temperature, moisture) are re‑calibrated. Leak tests on piping—often pressurizing the loop with nitrogen and checking pressure drop—are essential because leaks can waste 20–30% of compressor capacity (pharmaceuticalmanufacturer.media).

Compressed air performance qualification (PQ)

PQ validates air quality across the network, defining per‑line specifications (often ISO 8573‑1 classes). Typical pharma requirements might be ISO Class 1.4.1—oil‑free, extremely dry, essentially zero particles. Example acceptance limits include total oil content ≤0.01 mg/m³ (ISO Class 1), pressure dew point ≤–40 °C (Class 1 water), and particle counts meeting Class 1 (≤10 particles 1–5 μm per m³) (www.atlascopco.com). Particulate contamination is measured via calibrated particle counters or by tapping filters. For microbial quality, teams sample at production‑critical points with an air sampler.

ISO 8573‑7 requires collection of controls (“blinds” and a sterility blank) that must yield <1 CFU (www.airbestpractices.com); practical sampling often draws ~1000 L of air onto agar plates (www.airbestpractices.com). Acceptance is typically “no growth” (especially for Grade A environments) or very low counts consistent with ambient cleanroom microbial limits. Points in contact with product or the highest‑risk processes are prioritized.

Sampler setup and monitoring frequency

Dedicated sampling ports (stainless steel) should be installed at each critical use point (www.pharmtech.com). During PQ, many protocols call for consecutive‑day sampling—often 3 days—to demonstrate consistency (www.pharmtech.com); laser counters provide immediate particle counts, while microbial plates are incubated to confirm low bioburden. Acceptance criteria typically include no particle alarms, dew point within spec, and “no growth” on plates, with alert/action limits defined based on historical data.

A monitoring schedule keeps systems in compliance: FDA and industry guides suggest routine retesting (e.g., quarterly or semiannually) and retesting after any system change. For clean steam, the generator is sampled weekly and each critical use point at least monthly, rotating across all points so each is checked at least every six months (www.gmpsop.com; www.pharmtech.com). Samples for endotoxin are collected aseptically and tested promptly (www.gmpsop.com).

Data‑driven rationale and energy stakes

Benchmark studies underscore the stakes. Inefficient air systems—leaks or poor filtration—risk product quality and can consume 20–30% more energy (pharmaceuticalmanufacturer.media). HVAC/utilities can account for 60–70% of plant energy use (ispe.org). Targeting stringent ISO 8573‑1 Class 1 quality—or better—protects against hidden contamination; Class 1 effectively forbids visible particles and oil in the airstream (www.atlascopco.com). Numeric limits—oil <0.01 mg/m³, microbial “no growth”—and worst‑case testing at highest usage provide data‑backed confidence that utilities meet pharmaceutical quality requirements.

Examples of acceptance criteria (PQ focus)

Steam condensate: Conductivity ≤1.1 µS/cm @20 °C; TOC ≤0.5 mg/L (www.pharmaguideline.co.uk); endotoxin <0.25 EU/mL (www.gmpsop.com; www.pharmaguideline.co.uk); total plate count <10 CFU/100 mL with no E. coli, Staph. aureus, P. aeruginosa, or Salmonella; non‑condensable gases <3.5%; dryness ≥90% (www.pharmaguideline.co.uk).

Compressed air: ISO 8573‑1 Class 1—oil ≤0.01 mg/m³; dew point ≤–40 °C; particles (1–5 μm) ≤10/m³ (www.atlascopco.com); microbial count “no growth” or consistent with Grade A air. System operation: filter pressure drop within limits; alarms functional; compressors run to full load.

Feedwater treatment and materials notes

Clean (or “pure”) steam is generated from pretreated water to avoid contaminants—analogous to WFI pretreatment (www.drugfuture.com). In OQ, verifying that the demineralization train is functional is routine (demineralizer). Where ion exchange media are used as part of demineralization, those materials are typically controlled under the same IQ/OQ documentation discipline (ion exchange resin).

Sampling hardware should be designed for compliance; installing dedicated stainless sampling ports at each critical point supports consistent compressed air validation (www.pharmtech.com). For point‑of‑use air filtration, pharmaceutical and food‑grade stainless housings help align materials of construction to GMP expectations (stainless cartridge housing).

Summary of the validation master plan

IQ locks down installation and documentation (materials, slopes, traps, safety, utilities, and certificates). OQ proves function under simulated operation—controls, alarms, calibrations, steam quality (dryness, superheat), non‑condensables, trap performance, leak tests, and pressure drops. PQ demonstrates multi‑day performance across all use points with numeric acceptance limits for water‑like condensate and ISO‑class air, including microbial controls and endotoxin for steam. Monitoring remains routine: weekly at the steam generator, monthly at critical points with six‑month rotation, and quarterly/semiannual compressed air checks—always retesting after changes. The payoff is compliance and efficiency in systems that can account for 60–70% of plant energy (ispe.org), where leaks alone can cost 20–30% of output (pharmaceuticalmanufacturer.media).