Particle Validation Standards

Certified and Customized Sets for Visual Inspection Training Programs

Visible particulates in injectable products can jeopardize patient safety. Therefore, reliable control of particulate contamination in fill and finish process steps is essential. Control measures include visual inspection of the final drug product to ensure it is "essentially free" or "practically free" of particles.

Our Particle Validation Standards comprise a broad range of custom-manufactured standards designed to validate the visual inspection process.

Certified Custom Defect Kits

Each kit is specially designed and supplied with a certificate of compliance & traceability.


Fabrication, processing, and inspection are performed under ISO 9001 QMS.


Reliability secured by over 40 years’ experience and global coverage from our site in North America.

Custom-Designed Kits to Fit Your Unique Requirements

A Range of Packaging Options

Standards are fabricated using customer-supplied containers and seals to ensure consistency. We support numerous packaging types:

  • Ampoules (Glass, up to 128 mm height)
  • Syringes (Glass, non-graduated)
  • Vials (Glass, up to 100 mL)
  • Cartridges (Glass, non-graduated)
  • CZ Vials | Syringes
  • Cryotubes

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Fill Solutions Supporting a Range of Applications

We offer three types of fill solutions:

  • Bacteriostatic water
  • HPLC high-purity water or WFI
  • Customer-supplied fill solutions, i.e, drug product, placebo, or custom solutions (subject to review and pre-approval of the SDS).

Colorization available for standard and custom solutions (upon testing).

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Standard and Customized Options

Visual inspection training kits are designed to replicate potential extrinsic, intrinsic, and inherent sources of product or process contamination.

We offer a range of standard and customized particle covering glass spheres | shards, polystyrene spheres, stainless steel shards, hair, fibers, rubber | plastic defects, and cosmetic defects (see table below). There are additional packaging options and associated cosmetic defects for glassware.

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Size Range (μm)

Available Sizes (μm)

Clear Glass Spheres

100 – 2000

100 - 600 (inclusive), 650, 750, 950 and 2000

Black Glass Spheres

100 - 1130


Clear Polystyrene Spheres

100 - 1000

100 - 500 (inclusive), 750 and 1000

Black Polystyrene Spheres

100 – 500


Red Polystyrene Spheres


Request availability

Glass Shards


Amber or clear

Fibers, any color (including clear or fluorescent)


Recommended to start at 500 μm

Stainless steel shards

100 +

100 - 1500

Rubber from stoppers/plungers



Gross underfill/overfill


Volume specified by customer

Variances in plunger height (syringes)


Height specified by customer

Cracks in glassware


Inquire about options




Hair (light, dark or mixed)

500 +

500 +

Cosmetic defects


Glassware/fill solution/sealing /stopper

Fully Personalized Solutions

Each standard set is created according to customer specification, based on:

  • Packaging type and size  
  • Fill solution | fill volume   
  • Particle material types | colors | sizes
  • Particle quantity per container    
  • Container quantity per particle type | size
  • Packaging cosmetic defects
  • Label specifications

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Improved Confidence

Fabrication of kits follow proprietary in-house processes following current ISO standards.

  • Skilled lab technicians highly experienced in validation standards production processes
  • Projects fabricated in dedicated labs with HEPA-filtered laminar flow hoods

Certificate of compliance & National Institute of Standards and Technology (NIST) traceability supplied with each kit.

  • Particle tolerance range
  • Particle lot traceability
  • Fill volume tolerance

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Flexible Solutions for Unique Products

Loose Particles for Lyophilized Products

We offer NIST traceable particles allowing you to seed products at your own site  and avoid potential degradation and loss associated with lyophilization.

High Viscosity Solutions

We accept emulsions, meaning no filtration is required at filling steps during fabrication.

Non-Standard Packaging Options

We can work with a variety of non-standard packaging (subject to evaluation), creating a bespoke service.

Bespoke Solutions to Meet Your Visual Inspection Requirements

Frequently Asked Questions - Particle Validation Standards

Particulates are mobile, undissolved particles (other than gas bubbles) that are inadvertently introduced to an injectable product.

Visible particulates in injectable products can cause an undesirable physiological response, representing a patient safety risk.

Ideally, automatic visual inspection (AVI) machines and human inspectors should be tested using separate particle validation standards for each potential type of contaminant in the manufacturing process.

No regulation currently addresses this. The process is considered valid as long as the inspection system can consistently detect the smallest recognized (i.e., threshold) particle. A consistent detection rate of about 80% is a key specification for both human and automated inspection systems.

After investigating potential sources of material contamination, particle validation standards that fairly represent those possible contaminants should be selected. As an example, the following guidelines represent standard contaminants by container type:

  • Ampoules – glass and fiber
  • Vials - glass, fiber, rubber stopper, and aluminum
  • Syringes – glass, fiber, plunger material, and stainless steel

Additionally, potential contaminants or conditions unique to each process, such as overfilled and underfilled standards, plunger position standards, cosmetic defects, and blanks, may be included.
Custom particles are an option if stock materials do not replicate a particle contaminant.  Customers may submit their material to our technical team for evaluation.

It is highly recommended to have a set of standards made for each type of glassware as particles will act differently depending on the shape and size of the container and fill volumes. Packaging types such as amber glassware adds a level of difficulty to the detection process.

No, Customers are required to supply packaging as used in their current manufacturing process (or aligned against their visual inspection training needs). They must be provided in the same quality and cleanliness conditions. To achieve this, you should collect your containers after the washing procedure but before filling. If this is not possible or practical, unopened containers from your glass supplier may be provided.

Bacteriostatic water is the traditional fluid fill except when the usual product fill is significantly different in viscosity or turbidity.

In these cases, particle validation standards may be created with the customer product (a safety data sheet is required prior to quoting).

Rubber stoppers or plungers should have some type of coating on them to keep particles from sticking to them (like Teflon®; OmniFlex® or FluroTec® barrier film stoppers).

Rubber stoppers or plungers with a non-stick coating enhance the free flow of particles in solution. Particles may adhere to uncoated rubber stoppers, rendering the standard unreliable. Stoppers with elaborate 3D structures, such as those used for lyophilized products, may also trap particles.

Related Assets


SoloHill® Particle Validation Standards

PDF | 717.2 KB

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