FieldSENSE – A Brief History
fieldSENSE60 Personal RF Monitor – Overview
fieldSENSE 2.0 Personal RF Monitor – Overview
How to take voice notes
How the fieldSENSE60 works
How the refurbishment program works
How to start using your fieldSENSE
How to use the harness attachments
How the built-in fall detection and alarm works
Mankind has relied on various forms of communication through the ages. Our ability to communicate effectively is what has really allowed us to become a global society. As a global village we’ve only been able to accomplish this with our ability to communicate over vast distances in very short periods of time. In this series we’ll be discussing how this has all been enabled by RF and this whole field is barely 200 years old.
Just over 200 years ago Hans Christian Ørsted was busy with an experiment where he passed electoral current through a conductor and noticed a compass needle a distance away deflecting later, Faraday proved the opposite is also true, if he were to alternate a magnetic field, he would induce an electric current. All of these lay the foundations for what is now known as Maxwell’s equations, the unification of electricity and magnetism and this brings us to the next step, what is RF?
Communication systems rely on your ability to transmit information. Action at a distance, the phenomena first observed by Hans Christian Ørsted over 200 years ago, is the basis of our communication systems these days. RF is really just a subset of the electromagnetic spectrum and it is the frequencies which have been found to be most suitable for telecommunications purposes.
Making use of RF for telecommunications systems relies on transmitting antennas and receiving antennas. Now, you may have heard of the near field and the far field before. Well, the near field is really the area about a transmitting antenna where there is large amounts of reactive energy. Really, where the relationship between the electric and the magnetic field are not yet fully established. the far field is what we use when working with power densities for a receiver. It is really important to understand all these fundamental characteristics of electromagnetics to make effective use thereof.
When working near transmitting antennas the power densities you may encounter can easily exceed the safe working limits as one of the side effects of RF is its ability to heat biological tissue these levels need to be kept in check.
Transmitting antennas are more ubiquitous than you may realize. Professions such as HVAC, waterproofing and window washers are very often up on base stations not realizing it. Anybody who works near transmitting antennas should be taking necessary steps to ensure their levels of exposure are within the safe working limits.
The strength of RF is also its weakness we have no inbuilt sensor which allows us to quantify the levels which we’re exposed to. Those working around transmitting antennas, where the levels may exceed the safe working limits, really do need to have some way of quantifying these to ensure they are not in harm’s way.
To avoid overexposure to RF the accurate assessment of the levels present in the environment in which you’re working is really important. This is accomplished through the use of a personal RF monitor. These devices are specifically designed to correctly assess both the E- and the H-field and also all the sources present around these transmitting antennas and reported to you in terms of the safe working limits. This way you will know as you begin to approach these limits or even exceed them allowing you to take the necessary corrective actions in time.
As our dependents on telecommunications has grown so too has the need to convey more and more information using the same scarce resource with electromagnetic spectrum. This is brought about the evolution of the communication protocols we use. What originally started as a cell phone in 1973, the first iPhone in 2007, and right now we’re up to 5G handsets able to convey vast amounts of data in a very short period of time we can only imagine where this is going. This is becoming the basis of our economies and will be for many years to come.
Who needs RF anyway?
Action at a distance
What is RF?
The characteristics of RF
Is too much of a good thing, bad?
Who is at risk of overexposure?
How do I know if I am being overexposed?
What is a personal RF monitor?
The evolution of telecommunications
FieldSENSE personal RF monitors each have a total of six orthogonal E- and H-field probes to ensure that the combination of all sources of radiation from all angles are correctly measured and assessed in accordance with safety limits.
RF Safety guidelines use the radiated power density, S in milliWatt/cm2 or Watt/m2, to assess exposure to electromagnetic fields in a given situation. This is derived from the measured E- (electric) and H- (magnetic) fields. To accurately assess a given exposure situation, both of these should be measured, especially when working very low in frequency around FM transmitters for instance. Only measuring E-field in these instances can lead to inadvertent RF overexposure.
The monitors have an advanced E- and H-field data logger, which records all user measurements so that they can be easily accessed over a USB connection to a PC in the office. Additionally, the data can be viewed in real-time over the USB connection with the PC application.
The inbuilt logging feature allows for quick voice note taking, which can be accessed later in the office. The data is paired with the logged E- and H-fields so specific exposure conditions can easily be tagged.
The exposure limits, such as the FCC (NCRP), SC6 or ICNIRP limits, are all shaped over frequency. As such, PPE must also have a shaped probe response to accurately measure in accordance with it. RF monitors without a shaped response are inaccurate and can result in an individual being overexposed.
The devices have an inbuilt fall detection system which sounds an alarm should the user accidentally fall. The alarm is easily silenced should the user still be conscious but, should they have been knocked unconscious the sounding alarm will attract the attention of colleagues. This way they are able to immediately initiate rescue actions thus reducing the potential effects of suspension trauma following a fall at height.
FieldSENSE devices use high brightness amber LED indicators for direct sunlight visibility and have a loud buzzer to ensure the user won’t miss a thing. Additionally, it is specifically designed to be operated whilst wearing gloves.
Devices come with an easily adjustable wrist strap to ensure comfortable attachment while working. Additionally, the fieldSENSE60 harness attachment mechanism has been completely redesigned to include a coiled lanyard system. This facilitates the smooth handling of the device during operations while still remaining visible and audible. Should the device be dropped there is no risk of it falling off the site. A tripod attachment point on the base of the device allows for setting up remote monitoring of a site, or for attaching an extension pole.
The devices use readily available AAA (LR03) batteries.
The device has a custom bevelled design that fits tightly into the user’s hand with a textured soft elastomer surface and grip ridges ensuring no fumble moments.
The devices have a co-moulded enclosure with a base layer of polycarbonate which is typically used in riot shields, and an outer elastomer layer made of TPU which is designed for hard wearing environments. The design provides for IP64 dust & moisture ingress rating as well as IK08 impact protection.
Shipped in a heavy-duty zipper case with a custom moulded insert makes for even further protection of the device.