Medical Equipment Risk Classification: The Fennigkoh & Smith EM Score Explained

Short answer: the Fennigkoh & Smith model, published in 1989 by Larry Fennigkoh and Brigid Smith, scores each type of medical device on three factors: function (2 to 10), physical risk (1 to 5) and maintenance requirements (1 to 5). The sum is the equipment management (EM) number. Devices scoring 12 or more go into the scheduled maintenance program; lower scores may be left out or maintained less often. Many programs also adjust for incident history, and life-support equipment is conventionally included whatever it scores.

Most biomeds have met the EM score in school or on a CBET study guide and then never seen it used on the job. It is still the clearest way to explain why one device gets a PM every six months and another gets a visual check when it breaks. This guide gives the full scoring tables, works through examples, and explains where the score fits in a modern program.

How is the EM number calculated?

EM = Function + Physical risk + Maintenance requirements, scored for a device type (not each individual unit). Some versions add an incident-history adjustment, covered below.

Function (2 to 10)

Physical risk (1 to 5)

Maintenance requirements (1 to 5)

Incident history (an adjustment)

The model also lets a device type's failure history move its score. The levels usually given run from significant (more than one incident every six months) through moderate, average and minimal to insignificant (fewer than one in the past 30 months). Versions differ on how many points each level is worth, so if your program uses it, write down the values you chose and apply them consistently.

Worked examples

These are illustrations of the arithmetic, not recommended scores. Your equipment committee may reasonably score the same device differently.

Two things stand out. Life support and therapeutic devices clear 12 almost automatically because function carries most of the weight. And a device below 12 is not "no maintenance": it means the program may choose not to schedule it, or to maintain it differently, and has to say so.

Is 12 a rule?

No. Twelve is the threshold in the original model and the one most textbooks repeat, but the cut-off is the program's choice, and many programs add a middle band (for example, scores from 8 to 11 maintained at a longer interval). Treat the score as a documented starting point for a decision a qualified person makes, not as the decision.

Where does risk scoring fit today?

CMS lets a hospital depart from manufacturer maintenance recommendations through an alternate equipment management (AEM) program, based on a documented risk assessment by qualified personnel and generally accepted standards of practice; CMS points to ANSI/AAMI EQ56 as an example (CMS S&C 14-07-Hospital). Some equipment cannot go on an AEM program: imaging and radiologic equipment, medical lasers, and new equipment without enough maintenance history stay on the manufacturer's recommendations. An EM-style score is one common way to document the risk part of that assessment.

The model has limits. It scores a device type, not a fleet; it does not consider how heavily a device is used or how critical it is to a particular department; and it predates networked devices and cybersecurity. Later models add factors like these. Whatever model you use, the hospital owns the program and its decisions. Our guide to what CMS and Joint Commission surveyors expect covers the records side.

For independent service companies

If you maintain equipment for hospitals, you will rarely set their risk scores, but your technicians may be asked to help, and CMS says the people doing the risk assessment must be qualified whether they are employees or contractors. What you can always do is make sure your records carry the device's risk level and the source of its interval, so the hospital's program and your PM schedule agree.

How Bravio handles risk

In Bravio, risk levels are named your way ("High", "Life Support", "Class 1") and each maps to a fixed severity (Low, Medium, High, Critical) so lists can be sorted by it. A separate Critical flag marks equipment where every scheduled PM has to be completed. Equipment classes carry a default risk level and PM interval that every model in the class inherits, and asset templates have an optional Fennigkoh & Smith calculator that suggests a risk level from the three sub-scores (High at 12 or more; Medium at 8 or more, a common cut-off rather than a cited requirement). Equipment nobody has assessed is shown as unassessed, never as low risk. Equipment classification is switched on per account on request. See medical equipment PM software and CMMS for HTM teams.