A Complete Guide to Metal Detectable Silicone Rubber
What is Metal Detectable Silicone Rubber?
Metal detectable silicone rubber is a specialised type of silicone designed for use in industries requiring stringent safety and contamination prevention measures, such as food processing and pharmaceuticals. The material is infused with metal-detectable additives that allow small fragments to be identified by standard metal detection systems if contamination occurs. This unique property minimises the risk of undetected foreign objects in production lines to ensure product safety and compliance with regulatory standards such as FDA 21 CFR 177.2600 (Rubber Articles Intended for Repeated Use).
In addition to its detectability, metal detectable compounds retain the inherent benefits of silicone, such as flexibility, thermal stability and resistance to chemicals and environmental factors. It is particularly suited for applications involving direct food contact, thanks to its non-toxic nature and ability to withstand extreme temperature conditions.
Appearance
Only available in blue.
Tear Strength
Resistance
to tearing between 21N/mm and 23N/mm.
Specific Gravity
Formulated
for a density of between 1.26 g/cm3 and 1.35g/cm3.
Hardness
Available
with a 45ᵒ Shore A or 75ᵒ Shore A hardness.
Tensile Strength
Tensile
strength between 8.9N/mm2 and 9.2N/mm2.
Elongation at Break
Flexibility
between 360% and 500% without breaking.
Temperature Range
Operates
effectively between -55°C and 200°C.
Properties
Good
mechanical properties
Learn how metal detectable silicone is formulated, how it differs from other specialist grades and common applications within the industry.
How is Metal Detectable Silicone Rubber Made?
The production of metal detectable silicone rubber begins with the base silicone polymer, polydimethylsiloxane (PDMS). This polymer is reinforced with fillers such as silica to enhance its mechanical properties and stability. To impart detectability, finely distributed metal particles or other metallic additives are integrated into the silicone matrix. These additives enable the material to be identified by metal detectors without compromising its performance or flexibility.
During manufacturing, the formulation is carefully controlled to meet industry-specific standards, including food-grade compliance. Curing agents, typically platinum-based systems, are used to cross-link the silicone polymer, creating a durable and elastic material. The curing process also ensures uniform dispersion of the metal-detectable particles to help with consistent detectability across the entire material.
The finished product undergoes rigorous quality control testing to verify its mechanical properties, heat resistance and detectability. Additional tests may include extractables and leachables analysis to confirm compliance with regulatory standards for food and pharmaceutical applications.

Advantages of Metal Detectable Silicone Rubber
Metal detectable silicone rubber offers several advantages that make it indispensable for contamination-sensitive industries. Its primary benefit is its ability to be identified by metal detection systems. This helps aid quick identification and removal of any material fragments during production. This reduces the risk of product recalls and ensures compliance with health and safety regulations.
The materials thermal stability allows it to perform reliably across a broad temperature range, typically from -55°C to 200°C. This makes it suitable for applications involving both high-temperature sterilisation and low-temperature processing. Additionally, its chemical resistance ensures durability in environments where exposure to oils, cleaning agents and other substances is common.
Metal detectable silicone rubber is non-toxic and can be formulated to meet FDA or similar regulatory standards. This makes it safe for direct contact with consumables. Its flexibility and resilience enable it to maintain a reliable seal or function even under repeated mechanical stress, contributing to its long service life and reducing maintenance costs.

Common Applications and Uses
This materials unique properties make it a useful material for industries where contamination prevention is paramount. Below are three key application areas:
Industries

Food Processing
In the food processing industry, metal detectable silicone rubber is used for seals, gaskets and O-rings in machinery that comes into direct contact with food products. Its ability to withstand high temperatures and cleaning cycles ensures reliability in demanding environments. If a fragment of the material inadvertently enters the production line, it can be easily identified and removed using metal detection systems, safeguarding product quality and compliance with safety regulations.

Medical & Pharmaceutical
In the pharmaceutical sector, this material is used in equipment such as transfer hoses, diaphragms and stoppers where contamination control is an important factor. Its detectability minimises risks associated with foreign material contamination, while its chemical inertness ensures compatibility with sensitive pharmaceutical formulations. The materials compliance with stringent regulatory standards further reinforces its suitability for pharmaceutical applications.

Industrial
In industrial manufacturing, metal detectable silicone finds use in conveyor systems, packing machinery and other equipment requiring dynamic seals and components. Its resistance to wear, temperature fluctuations, and exposure to oils and greases ensures long-term performance. The added benefit of metal detectability enhances safety in production environments, especially where contamination could lead to costly downtime or product recalls.
Material Compound Datasheets
Metal detectable silicone can be extruded in two different hardnesses, each suitable for different applications. The properties and characteristics of these hardnesses may differ. Please see the downloadable PDF material compound datasheets for this information.
Looking for a different grade of Silicone?
As well as metal detectable Silicone, we are also able to manufacture rubber sealing products in a selection of other specialised Silicone compounds. This includes general purpose silicone, metal detectable silicone, high temperature silicone and flame retardant silicone.
Contact Us
With over 50 years' experience in the rubber sealing industry, our team has extensive experience in finding sealing solutions for our customers. Contact our experts via phone or email for sealing advice or bespoke quotations.
Email:
sales@sealsplusdirect.co.uk
Telephone:
01425 617722