1. •
Definitions
•
Purposes
•
Metrology Basics
•
Role of BMET
•
Role CE
•
Documentation
•
Conclusion

2. Definitions
Measurement is the process or the result of determining the
ratio of a physical quantity, such as a length or a mass, to a unit of
measurement, such as the meter or the kilogram. The science of
measurement is called Metrology.
Instrumentation is defined as the art and science of
measurement and control. An instrument is a device that measures
and/or regulates process variables such as flow, temperature, level,
or pressure.
Calibration is a comparison between measurements, one is
set (standard) value and the other measured (practical) value that
leads to process of corrective actions when results are out of limits.
The accuracy of a measurement system is the degree of
closeness of measurements of a quantity to that quantity's true
value.

3. Definitions
The precision of a measurement system , also called
reproducibility or repeatability , is the degree to which repeated
measurements under unchanged conditions show the same
results.
High Accuracy
Low Precision
Low Accuracy
High Precision
A measurement system is designated valid if it is
both accurate and precise

4. Example
NIBP measurement supposed to be within
tolerance of 5 mmHg, therefore:
± 1 mmHg
± 2 mmHg
± 3 mmHg
± 4 mmHg
± 5 mmHg

5. By performing the test 3 times:
(a)
(b)
(c)
We notice all the readings within the tolerance but the following
points are reasonable:
• Figure (a): with low accuracy and precision is not acceptable and
requires calibration
• Figure (b): High Accuracy & precision , Calibration not required
• Figure (c): High precision and low accuracy close to the limit,
Calibration is recommended

6. Purpose of Measurement
The purpose of measurement is to provide information
about a quantity of interest - a measurand. For example,
the measurand might be the flowrate, potential
difference, or energy .. Etc.
No measurement is exact. When a quantity is measured,
the outcome depends on:
• The measuring system,
• The measurement procedure,
• The skill of the operator,
• The environment, and other effects.

7. Metrology Basics
• Metrology includes all theoretical and practical aspects of
measurement
• A core concept in metrology is (metrological) traceability,
defined as "the property of the result of a measurement or the
value of a standard whereby it can be related to stated
references, usually national or international standards, through
an unbroken chain of comparisons, all having stated
uncertainties.“
• Traceability is most often obtained by calibration, establishing
the relation between the indication of a measuring instrument
and the value of a measurement standard.
• Mistakes can make measurements and counts incorrect. Even if
there are no mistakes, nearly all measurements are still inexact.

8. BMET Role
 The basic program for BMET was established to prepare him/her for
conducting complete performance assurance and electrical safety
testing. Performs preventive/scheduled maintenance on medical
devices as required. Performs repairs and calibrations with the highest
degree of complexity or requiring expert diagnostic and repair skills,
among other responsibilities.
 With the advancement of medical technology field, the sophistication of
medical equipments is incremental every year, which requires highly
skilled BMET of well-established academic program. Although, certain
categories of medical equipments regulations required certified BMET or
certified service engineer to work with the equipment.
 Therefore, many original equipment manufacturers (OEM) have
emphasized that no one allowed to dismantle or service their products
such as life support equipments, sophisticated technology, and surgical
equipments unless OEM-certified technicians/engineers.

9. Clinical Engineer Role
 Biomedical engineers, by definition, apply the concepts, knowledge, and
techniques of virtually all engineering disciplines to solve specific problems in the
biosphere. When biomedical engineers work within a hospital or clinic, they are
more properly called clinical engineers.
 American College of Clinical Engineering has defined the Clinical Engineer as a
professional who supports and advances patient care by applying engineering and
managerial skills to healthcare technology.
 Cost-effective management of a medical equipment calibration and repair service
 Supervision of the safety and performance testing of medical equipment
performed by BMETs
 Training of medical personnel in the safe and effective use of medical devices and
systems
 Development and implementation of documentation protocols required by
external accreditation and licensing agencies
 Establish quality control (QC) & quality assurance (QA) program for medical
technology and maintains CMMS data secured and updated.

10. Documentation
BME Program of documentation was established to document and maintain the
important data according to the following procedure:
I.
Documentation of New Equipment:
I.
Equipment Details (Description, Manufacturer, Model, S/N, Control No, ECRI code, Vendor ..
etc.)
II.
PO Details (PO#, Date, Cost, Warranty type & period, Contract#, Install Date, Acceptance
Date .. Etc.)
II. PPM Documentation: (Equipment details, Test Equipment, Qualitative Check,
Quantitative Measurement, Electrical Safety, Calibration Data .. Etc.)
III. W.O. Documentation: (W.O.#, Equipment Details, Incident/Defect Details,
Repair Details, Utilized Spare Parts, Vendor Service Report as applicable, .. Etc.)
IV. All Original Service Reports to be filed by companies and copies only attached to
W.O. & PPM.
V. Quality Assurance Documentation by Clinical Engineers: Random samples of
PPMs & W.O. to be tested and documented for variety of equipments from
different disciplines.

11. Conclusion
 In light of the above, and by reviewing equivalent organizations practice
for medical equipment that obviously confirm the inarguable truth that
measurement and calibration is just a daily function of BMET as the
medical equipments are highly specialized, risky (involving life-support
and surgical equipments) and advanced technology that all demanding
the personnel –BMET- who is responsible about the service,
troubleshooting, and calibration to have specialized body-of-knowledge
and certified training from OEM, plus field experience in many
equipments is required.
 The Aim of this tutorial and future sessions is to keep an open
communication channel through interactive discussion of all
departmental emerging issues and to encourage the teamwork spirit by
sharing the ideas and knowledge of interest. In addition, the training
sessions also, will be documented and accounted for the benefits of
attendees.