Electromagnetic Fields
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ELECTROMAGNETIC FIELDS Measure: Why? • Measurement determines whether the • Measurement gives facts. For example, limit values for electromagnetic radiation public protection: On site measurements specified in laws, national regulations, and show the actual exposure levels. This can recommendations are being adhered to. help to allay unfounded anxiety, and can This is essential for occupational safety and be used to initiate further preventive action to protect the general public. – even if the values are well below the permitted limits. • Measurement gives reassurance. It is the most important step in effective protection. • Measurement makes sure. For instance, Take maintenance work on an antenna when planning high tension transmission array, for example: Are the transmitters lines or antenna arrays, spot check measure- switched off? Or is the field strength safe? ments show whether the field strength Do the actual values agree with the theor- simulation used in planning corres ponds to etical ones? reality. MEASURE: WHY? Measure: How? • Only standard-compliant measurements • Non-directional (isotropic) measurement is provide comparable, reproducible, and demanded by the standards. legally defensible results. • The permitted field strengths depend on • The measurement results must be under- the frequency. The measuring instrument standable, even for someone who is not must therefore be sensitive enough, have constantly concerned with electromagnetic a wide dynamic range, and be capable of fields. frequency selective field strength evaluation complying with regulations. • The electric and magnetic fields must be measured separately in the near field. • If the field strength is high or unknown, fit the instrument on a tripod and measure by remote control. MEASURE: HOW? Measure right! • Measurement means comparison with a known quantity. Since field strength units are also defined by national standards, our instruments are calibrated against quan- tities that are traceable to these standards. • Measuring equipment for outdoor use must be robust, dustproof, and weather- proof, to keep working accurately in the rough conditions of everyday use. • Simple operation avoids mistakes and leads to reliable and dependable results. • Minimum down time: We calibrate instru- ments in our own laboratory in rapid time. Recalibration is recommended every one to three years, depending on the device. MEASURE RIGHT! Monitor or meter? • Personal monitors are worn on the body • Meters provide overall or detailed results, • Area monitors are fixed measuring stations and give visual and audible warning when averaging and evaluating them auto- that monitor the field levels continuously. the field strength approaches the permitted matically if necessary. They are essential The results can be uploaded and recorded limit value. Company safety officers can use for operators, industrial safety officers, by remote control. They give everyone a them to protect everyone whose occupa- measure ment service providers, and public clear view of the level of exposure tion brings them into contact with electro- authorities for monitoring and qualify- magnetic fields, as well as tradesmen and ing transmitters and industrial equipment, visitors who are only occasionally exposed high tension lines, or transformer stations. to them. Data logger functions record the On site result storage and documentation exposure levels. on a PC with database support is import- ant when managing large quantities of measure ment data. MONITOR OR METER? NARDA SAFETY TEST SOLUTIONS THREE LOCATIONS – ONE GOAL Narda Safety Test Solutions is a global leader Our three sites are located at Hauppauge, in the development and production of Long Island (USA), Pfullingen (Germany) and measuring equipment for electric, magnetic, Cisano (Italy). Our goal is to provide you, the and electromagnetic fields. The fact that we user, with products tailored exactly to your own around 95% of all published patents for needs, using the highest quality in cutting- measuring such fields bears witness to this. edge technology. Choosing a Narda instrument is choosing a product from a company renowned for innovation, that is specialized in measure- WHAT WE OFFER ments for safety in electromagnetic fields (EMF), and that is continually building upon Our comprehensive range of products for its reputation in this sector. human safety in electromagnetic fields (EMF) includes broadband measuring instruments, selective measurement equipment, monitor- ing stations, and personal radiation monitors. Under our PMM brand, we offer instruments for assessing the electromagnetic compati- bility (EMC) of devices. As our customer, you can benefit from our program of services, including servicing, calibrating, and training. NARDA SAFETY TEST SOLUTIONS BROADCASTING, TELECOMS, MOBILE RADIO • Occupational safety: Safety zones must be • Protecting people and informing the gen- defined and observed when working in the e ral public: People want uninterrupted immediate vicinity of antennas. coverage, but at the same time, the radi- ation levels have to be kept low. NBM-550, the Narda Broadband Field Meter, uses isotropic E-field and H-field probes SRM-3006, the Selective Radiation Meter, to measure the electric and magnetic field shows the source and magnitude of indivi- components – simply, precisely, and non- dual contributions to the overall field strength directionally and evaluates them on site. RadMan and Nardalert, the clip-on moni- Area Monitore keep an eye on electromag- tors, keep an eye on your personal safety. netic fields, day and night. EFC-400, the Simulation Software, estimates the field situation by calculation before new antennas are installed. INDUSTRY, MEDICINE, PUBLIC SAFETY • Industrial safety: Low frequency and high EFA-300, the Electromagnetic Field Analyzer, frequency welding equipment, RF heating detects electric and magnetic fields from the for plastic welding, drying, bonding, lowest of frequencies right up to the high coating – whatever the application, the frequencies used in industry and medicine. limits must not be exceeded. ELT-400, the Exposure Level Tester, also measures pulsed magnetic fields in industry • Human safety in medicine: Magnetic and the home. Resonance Imaging, magnet therapy, dia- THM1176-PDA, the PDA-based magneto- thermy, hyperthermy – the diagnosis must meter, measures magnetic fields down to be correct, the therapy must benefit the 0 Hz. patient, and medical staff must not be put EHP-50D and EHP-200 automatically moni- in any danger. tor electric and magnetic fields on site. • Public safety: Close to high tension cables and transformer stations, proof that the field exposure is within the permitted limits is required. • Domestic appliances must meet the magnetic field properties specified in the international standard IEC/EN 62233. Security and identification tags (RF-ID) on goods must not produce excessive field levels. RADAR, AIR TRAFFIC CONTROL, RADIO LINK • Directional radio antennas strongly con- centrate the radiation power, and radar equipment uses extremely high impulse power levels as well. Primarily, those who work close to such equipment need pro- tection, but the exposure levels for the general public also need to be checked. NBM-550, the Narda Broadband Field Meter, can also measure the true power of pulsed electric fields if fitted with a suitable measur- ing probe. SRM-3006, the Selective Radiation Meter, can continuously register even short radar impulses with frequency-selective accuracy in Level Meter and Scope mode. RadMan XT and Nardalert S3, the clip-on monitors, keep an eye on your personal safety. RadMan XT, used as leak detector, can find radiation leaks caused by damaged feeders. POWER UTILITIES AND ELECTRIC RAILROADS • Power utilities use 50 or 60 Hz AC in EFA-300, the Electromagnetic Field Analyzer, transformer stations and high tension lines; detects electric and magnetic fields from inverters and switched mode power sup- the lowest of frequencies right up to the plies generate harmonics at several kilo- harmonic frequency range. hertz. SRM-3006, the Selective Radiation Meter, selectively registers the fields due to the tele- • Subways and railroads operate using high communications channels. value direct currents or alternating currents EFC-400, the powerful PC software appli- at 16 2/3, 50, or 60 Hz that cause magnetic cation, simulates the field situation by calcu- fields. lation, including all components – from DC up to telecommunication frequencies, and • Telecommunications equipment alongside can even determine the noise pollution level railroad routes or on high tension masts due to high tension lines, for example. can overlap high frequencies into the giga- EHP-50D, the stand-alone field analyzer, hertz range. automatically monitors the electric and mag- netic field strength on site. EVERYTHING YOU NEED! Electric field g m Magnetic field ) ) owave F ave ave Magnetic and electric field ave aves aves Long W Mediu W DC EL Short Short W VSW/VHF UHF Micr Heatin Centimeter W (EHF Millimeter W (SHF z z Hz 3 / 2 400 Hz 400 kHz 9 GHz 6 0 Hz 0 Hz 30 Hz 300 kHz 3 kHz 30 kHz 300 MHz 3 MH 30 MHz 300 GHz 3 GH 30 300 GHz 300 16 16 Radio Waves Microwaves AC Line voltage Television Cellular Radio WLAN Satellite Radio Industry and Medicine THM1176 8217 EHP-50D EHP-200 EFA-300B NBM with different probes EFA-300 NBM with different probes ELT-400 SRM-3006 with different antennas SRM-3006 with different antennas NIM-511 NIM-513 2600 8057 8057 8060 8830 SMARTS II RadMan