Innovators of Magnetic Particle
Inspection Materials for 40+ Years

Circle Systems manufactures testing solutions designed to increase the performance of your nondestructive evaluation and reduce the cost of your MPI process.

circle systems products

Leading the Way in Service and Chemical Technology in the MPI segment of nondestructive evaluation

customer service

Personalized Customer Service

Dedicated Account Rep
Direct Access to scientists for support

Cost Effective Solutions

Designed for Efficiency
Use up to 55% less product

Best in Class Technology

Chemical Technologies
& Best-in-Class
Manufacturing Methods

Circle Systems Is Borate Free

Products available that meet world-leading
European standards

Made In The USA

Proud to be US-Based in Manufacturing
& Support

Our Solutions

Circle Systems product offering includes three magnetic particle inspection categories designed for nondestructive evaluation of ferromagnetic materials. Mi Glow wet method particles in fluorescent and nonfluorescent, CircleSafe aerosols in water or oil carrier fluid, and Sir Chem dry method nonfluorescent magnetic particles.

Mi-Glow® products offer fluorescent and  nonfluorescent magnetic particles for use in wet  method inspection. These materials include unique  application materials such as underwater inspection  media, convenient packaging, and a full line of supporting materials such as white contrast paint, corrosion inhibitors and advanced wetting agents.

CircleSafe® is a complete line of magnetic inspection aerosols. Our CircleSafe® products are packaged with a carbon dioxide propellant to reduce the environmental and safety hazards typically associated with butane and propane propellant based aerosols. CircleSafe® aerosols are available in fluorescent yellow-green, nonfluorescent black or dual red particles in either water or oil media.


Sir-Chem® nonfluorescent dry method inspection particles are offered in a variety of colors. These dry powders include a special line of products in a bonded form to decrease the amount of dust dispersed in the air during inspection – ideal for close indoor work areas.


About Circle Systems

Circle Systems has been developing and manufacturing magnetic inspection particles for over 40 years.  Circle’s industry focus is the development of Magnetic particle testing materials including wet method particles, dry method particles, ready to use aerosols, underwater magnetic particles, and water conditioning agents for the NDT community. Originally named Circle Chemical Co., we have been rooted in the chemistry of magnetic particle inspection since our early days  proudly serving the NDT community and manufacturing in the USA since 1956.

Our Solutions

Our approach has led to products that utilize state of the art chemical technologies, best in class manufacturing methods, and a broad product line that is unmatched amongst other MPI manufacturers in the NDT industry. Circle’s dedication to innovation provides our customers with the highest performing and cost-effective magnetic particle testing solutions.

Circle Systems has established our reputation as a trusted magnetic particle testing supplier to some of the most notable manufacturers and nondestructive testing companies around the world.

Circle has great customer service that is very responsive. I like that I always get a live person, not a recording, when I call Circle. Circle has a very good range of MT products with excellent delivery times.