Every batch of parenteral products must be inspected for visible particles before release. In Europe, the reference method is chapter 2.9.20 of the European Pharmacopoeia, Particulate contamination: visible particles. The chapter is short, but every detail of theinspection station has an impact on what operators can actually see. This guide explainswhat the text requires, what the newer chapter 5.17.2 adds, and how to set up a stationthat is both compliant and reliable.

What does Ph. Eur. 2.9.20 require?

Chapter 2.9.20 describes a simple viewing station and a standard observation method. Itis a mandatory test method for the visible particle inspection of parenteral preparations.

The viewing station must include:

- A matt black panel of suitable size, held vertically.

- A non-glare white panel of suitable size, held vertically next to the black panel.

- An adjustable lampholder with a shaded white light source and a suitable diffuser.

- An illuminance of 2000 to 3750 lux at the viewing point. The text adds that highervalues are preferable for coloured glass and plastic containers.

The observation method, step by step

1. Remove any adherent labels, then wash and dry the outside of the container.

2. Gently swirl or invert the container, taking care not to introduce air bubbles.

3. Observe it for about 5 seconds in front of the white panel. Dark particles stand outon the white background.

4. Observe it for about 5 seconds in front of the black panel. Light particles and fibresstand out on the black background.

5. Record the presence of any particles.

The United States Pharmacopeia describes a comparable approach in chapter <790>Visible Particulates in Injections, which is useful for companies supplying both markets.

What chapter 5.17.2 adds

Since 1 January 2021, the European Pharmacopoeia also includes general chapter 5.17.2, Recommendations on testing of particulate contamination: visible particles (EDQMannouncement). It is not mandatory, but it is increasingly used as a reference byinspectors and auditors.

It covers, among other topics:

- The sources of foreign particles and the stages where inspection takes place:manufacturing, quality control and stability testing.

- AQL inspection after a 100% inspection, referring to ISO 2859-1.

- The probabilistic nature of visual inspection: detection is never 100% certain, which iswhy conditions must be controlled.

- How to demonstrate that a product is "practically free from particles".

For products that are difficult to inspect, such as coloured solutions, amber glass, plasticcontainers or viscous products, the EDQM recommendations mention measures like light intensities above 3750 lux, inspection against both backgrounds and inspection times longer than 5 seconds per container (GMP-Compliance summary).

Five practical points for a more reliable inspection

Meeting the minimum requirements is one thing. Getting consistent detection, shift aftershift, is another.

1. Uniform light. Hotspots and shadows on the container create false alarms and hidereal particles. The illuminance should be stable over the whole viewing area, not onlyat its centre.

2. No glare. Reflections on glass are the main source of visual fatigue. Matte panels andcontrolled, directional light reduce them.

3. Measured illuminance. Check the lux level at the viewing point regularly with acalibrated luxmeter and record the results for audits.

4. Operator comfort. Inspection is repetitive and tiring. A light source that does notemit heat and a station that adapts to each operator help keep detection rates stable.

5. Magnification when needed. A low magnification (×2) helps with small containersand fine fibres without changing the method.

MIRA 2: a compact station designed for Ph. Eur. 2.9.20

MIRA 2 is a compact visual inspection booth developed by L.E.S.S. for vials, syringes,ampoules and infusion bags. It is designed to support inspection in line with Ph. Eur. 2.9.20and USP requirements.

- 3,000 lux at 15 cm, within the Ph. Eur. range, with 5400 K daylight and continuousdimming from 20 to 100%.

- Switchable black and white glare-free backgrounds, changed with a simple slider.

- An integrated ×2 anti-reflective magnifier. No heat at the lighting head, with tilt and yaw adjustment.

- Only 2 kg and 42 × 25 × 40 cm: it fits on a lab bench and moves between workstationsin seconds.

Its uniform illumination comes from LuxiBright® technology, which produces directionallight without the hotspots of conventional LED panels.

In practice: a veterinary pharmaceutical manufacturer equipped 9 MIRA 2 stations toinspect 100% of its injectables. Read the MIRA 2 case study.

Frequently asked questions

What illuminance does Ph. Eur. 2.9.20 require? Between 2000 and 3750 lux at the viewingpoint, with higher values preferred for coloured glass and plastic containers.

How long should each container be inspected? About 5 seconds in front of the whitepanel and 5 seconds in front of the black panel. Chapter 5.17.2 suggests longer times fordifficult products.

Is chapter 5.17.2 mandatory? No. It is a recommendation that complements themandatory method of chapter 2.9.20.

What is the difference with USP <790>? Both describe a visual inspection against blackand white backgrounds under controlled light. Companies supplying Europe and theUnited States should check both texts.

Ready to upgrade your inspection station?

Whether you are setting up a new inspection room or replacing ageing booths, our teamcan help you choose the right configuration. Request a quote or discover our visualinspection lighting.