Select Page


EMI Site Surveys, On-Site Testing, and In-Situ Testing

Keystone Compliance has established a strong reputation as an industry leader in Electromagnetic Compatibility testing (EMC testing). Our testing expertise includes EMC testing in one of our many EMC test chambers or outside our lab. Our field testing includes EMI site surveys, EMC on-site testing, and EMC in-situ testing.

Request a quote to receive expert EMI site survey testing services tailored to your specific needs,

What are EMC, EMI, and RFI?

EMI and RFI are used interchangeably. The difference between the two is that EMI includes any frequency of electrical noise, whereas RFI refers only to specific subsets of electrical noise.

EMC measures how well electrical devices can function while being hit with EMI (released energy from another electrical device). EMI is the problem, while EMC determines how well that problem can be handled.

General EMI and EMC Site Surveys

An EMI site survey provides the electromagnetic environment of a facility. Essentially, a site survey determines the electromagnetic waves and radio frequency (RF) that are active in a location. Keystone Compliance can determine the frequencies and levels of RF and EMI at a location.

The system being tested is the combination of the installed EUT and its surrounding RF environment/equipment. Since the installed RF environment is part of the system, tests have to be done in-situ; that is, tested in place.

On-site testing is similar because it takes place where the EUT is located, but that does not imply that the EUT cannot be moved. However, if the EUT is moved it may change the system configuration.

Common Site Survey Testing

An increasing number of facilities are looking to expand their ability to block RF interference. We work with facilities to determine the shielding effectiveness of buildings and rooms to block electromagnetic signals.

Facilities that frequently require EMI site surveys may include military installations, hospitals, schools, factories, offices, and residential locations where medical clinics are located.

There are several purposes for a site survey.

Security is a growing concern, especially in the interest of data protection and electromagnetic pulse (EMP testing) protection.

Health and safety are two other motivating factors. Another catalyst for completing a site survey is faulty equipment that is being impacted by RF.

A growing site survey need is shielding effectiveness. An increasing number of facilities are looking to expand their ability to block RF.

The threat of EMP attacks is growing. Keystone Compliance works with the military, utilities, defense contractors, and hospitals. Their objective is often to determine the effectiveness of buildings and rooms to block electromagnetic signals.

EMI and EMC Site Surveys for Implantable Devices:

An Electromagnetic Interference site survey (EMI site survey) is an independent assessment of potential EMI risks. These risks might interfere with an implantable electrical device such as a pacemaker or defibrillator.

A site survey is conducted by taking various electromagnetic measurements throughout the facility. Keystone Compliance uses a broad range of industry-accepted standards and specifications to determine which electromagnetic fields exist.

Following completion of the on-site survey, Keystone Compliance provides the customers with a detailed site survey report. This report identifies EMI sources and zones that have the potential to interact with an implantable electrical device.

Keystones EMI On-Site Testing and IN-Situ Testing Capabilities

Not every piece of equipment is mobile or can fit in an EMC test chamber. When circumstances do not permit chamber testing, Keystone Compliance can complete EMC on-site testing for this equipment. On-site EMC testing is often referred to as in-situ EMC testing.

Testing on-site can take several different paths. The testing can occur in an isolated location, where ambient signals are minimized. If that is not a possibility, the EMC compliance testing can occur right on the factory floor or in the fixed location of the equipment. The testing can include immunity and emissions testing.

The immunity and emissions testing are completely automated. They follow the same test procedures as if the testing were occurring in the EMC chamber. Ambient signals are identified and considered when assessing the performance of the device being tested.

Some of the more common site survey test scopes include conducted emissions, EMF, and microwave field surveys. We also provide power quality, radiated magnetic field, stray current, and surveillance testing as well.


EMC (Electromagnetic Compatibility) In-Situ testing is used where manufacturers of large or installed equipment, or equipment that may require extensive power or special support not provided by the lab.

Keystone Compliance will create a test plan to include emissions, immunity, safety, and risk assessment necessary for medical, military, industrial, and commercial equipment for certification to international standard requirements for EN61010-1, EN60204, EN60601-1, and EN61326.

Keystone’s EMI/EMC compliance team is experienced at problem resolution and will offer engineering guidance to rectify any failure issue that may arise to successfully complete your In-Situ test program.


Keystone Compliance has established a strong reputation for being an industry leader in EMI (Electromagnetic Interference) Site Surveys at the client’s location. The independent assessment of potential interference risks is determined by taking various electromagnetic measurements using a broad range of industry-accepted standards and specifications to identify EMI sources that have the potential to interact with electrical devices.

Expert EMI Site Survey Compliance Testing

Similar to our in-house testing, our on-site testing is customer-focused. There is communication throughout the entire test program. We diligently complete the testing and provide a thorough test report. We are ISO-17025 accredited and our test reports are recognized around the world.

Our EMC engineers are very experienced at problem resolution. They offer engineering guidance that helps overcome obstacles that might arise. Additionally, our equipment is portable and can accommodate tight spaces.

With a large staff and redundant equipment, we can move quickly. Lead times on scheduling are short. We can also assist in developing a test plan as well. Our EMC site survey expertise can identify the areas to focus on. Our on-site testing of equipment is streamlined. We do not over-test. Nor do we allow ambient signals to cloud the test results.

Ready to work with the best EMC test lab in the world? Find out why so many companies work with Keystone Compliance for their regulatory compliance testing needs. Contact Keystone Compliance to discuss completing a site survey or on-site EMC testing.