Water Safety Compliance: Exploring John Crane’s NSF 61-Certified Mechanical Seals

It's been nearly 100 years since John Crane pioneered the first mechanical seal. Since then, our technologies have supported water conservation in some of the world's toughest industries. We're continuing this legacy by providing a portfolio of NSF 61-certified O-ring pusher seals and separation seals that help our customers safeguard drinking water systems.

“NSF 61-certified” products are certified to NSF/ANSI 372 and conform with the lead content requirements for “lead free” plumbing as defined by California, Vermont, Maryland and Louisiana state laws and the U.S. Safe Drinking Water Act.

Why Do NSF 61, ANSI 61 and CAN 61 Standards Matter?

NSF 61, ANSI 61 and CAN 61 are rigorous guidelines developed to protect public health by ensuring materials and components used in water systems do not introduce harmful contaminants. These certifications establish strict health-based criteria to limit chemical leaching from materials, components and devices into the water supply. When products that come into contact with water systems adhere to these guidelines, it helps ensure clean, safe drinking water and contributes to public trust.

Learn more about the difference between NSF 61, ANSI 61 and CAN 61 standards and keep exploring their regulatory importance.

Which John Crane Technologies Are NSF 61-Certified?

John Crane's NSF 61-certified products reflect our commitment to reliability, efficiency and safety and are designed to address the complex requirements of water system safety. Below, we'll explore the specific models, material compositions, applications and benefits that define our NSF 61-approved technologies.

NSF 61-Approved O-Ring Pusher Seals

Key components in water treatment systems, such as O-ring pusher seals, ensure consistent, leak-free operation even in changing temperatures. John Crane's NSF 61-certified O-ring pusher seals are available in a wide range of sizes, ensuring flexibility and adaptability for various applications. Our cartridge-style O-ring pusher seals — including Type 4600, Type 5600, Type 4610, Type 5610, and Type 5610V — are engineered for durability and easy installation in demanding environments.

For applications requiring additional flexibility, our Type 8-1, Type 8-1T, Type 8B1 and Type 8B1T, sized from 0.5” to 7”, offer expanded options for environments with varying temperature ranges.

Each O-ring pusher seal is constructed using NSF 61-approved materials, such as carbon or silicon carbide for the seal faces, EPDM or fluorocarbon O-rings and durable 316 stainless steel metalwork. This robust combination forms an effective barrier against potential contaminants, helping preserving water quality across municipal and industrial settings.

Keep exploring John Crane's NSF 61-certified O-ring pusher seals.

NSF 61-Certified Split Seals

Split mechanical seals are designed for ease of installation and maintenance, making them a preferred option in larger water systems where frequent service or minimal downtime is essential. John Crane's approved split seals including the Type 3740 and Type 3740XL, are available in sizes from 1.375” to 12” and are manufactured at our Morton Grove facility. This range provides flexibility for varied applications that require efficient maintenance without extensive system disassembly.

Built with materials like carbon and silicon carbide for the seal faces, Viton for O-rings and sealing element and alloy X-750 for the retaining ring, these seals are optimised for resilience and longevity. Their wear-resistant design helps ensure high performance in demanding conditions, providing water treatment operators with a reliable, low-maintenance solution.

Learn more about John Crane's NSF 61-certified spit seals.

Elastomer Bellow Seals (Pending NSF 61 Re-Approval)

With rigorous NSF 61 certification standards requiring re-approval every year, John Crane is currently in the process of renewing our elastomer bellow seals for NSF 61 approval. Designed to handle minor misalignments and thermal expansion, our elastomer bellow seals deliver essential flexibility and reliability within fluctuating water systems. Models Type 1, Type 2, Type 21, Type 2100, Type 5611 and Type 5611Q are manufactured across our Morton Grove and San Fernando facilities and cover a range of sizes from 0.375” to 1.750” to suit diverse water system requirements. These durable, chemically resistant materials are compatible in diverse water treatment environments and help reinforce water quality and system reliability.

Keep exploring John Crane's elastomer bellow seals.

What Are the Requirements for NSF 61 Certification?

NSF 61, ANSI 61 and CAN 61 certification requires a commitment to quality and safety across every step of the manufacturing and control processes. We create each of our NSF/ANSI 61-certified products using NSF 61-approved materials, including EPDM and Viton O-rings, silicon carbide or carbon seal faces and 316 stainless steel metalwork. Each of these materials is tested and validated to ensure they meet the high standards necessary for water safety, reducing the risk of chemical leaching and preserving water quality.

John Crane products that hold NSF/ANSI 61 approval are produced at our NSF 61-approved facilities in Morton Grove and San Fernando, where each step of the production process is carefully monitored to meet strict compliance standards. This traceable manufacturing process helps ensure that each batch of products adheres to NSF 61 requirements while maintaining John Crane's high standards of quality and safety.

Documentation is essential for compliance. Each batch is backed by detailed General Arrangement (GA) drawings, which provide full traceability and ensure alignment with John Crane's safety and performance standards. This structured approach allows us to deliver products that meet NSF 61 requirements from first design to final production.

What Are the Market Advantages of John Crane's NSF 61-Approved Technologies?

Selecting John Crane's NSF 61-certified products offers a comprehensive approach to water safety and operational efficiency. Engineered for reliability and efficiency, our seals not only meet rigorous NSF 61 standards but also provide long-lasting performance across various demanding applications.

With more than a century of experience supporting essential industries like wastewater management, food and beverage, pharmaceuticals and chemical processing, John Crane's NSF 61-certified products bring a critical layer of quality and dependability to water systems, where reliability and operational integrity serve as the backbone of continuous, safe water distribution. Our NSF 61-approved products are also compatible with all non-John Crane seals, allowing seamless integration into existing systems and saving operators valuable time on additional testing or compliance adjustments.

Supporting Reliability and Safety with NSF 61-Certified Seals

John Crane's commitment to water safety and quality is the foundation of every NSF 61-certified product we offer. By providing a comprehensive range of approved sealing solutions, we help operators and OEMs meet the highest standards for public health and regulatory compliance. Learn how NSF 61-certified products can support the safety, reliability and compliance of your water systems. To keep exploring NSF 61, ANSI 61 and CAN 61 standards and their role in maintaining the integrity of drinking water, read the first instalment of our water compliance series.