1 CHAPTER 4 ANALYSIS OF SECURITY ISSUES OF ATM 4.1 ATMs SECURITY ISSUES The security and vunerabiity are opposite sides of the same coin, an Automated machine becomes vunerabe due to weakness of its security. Automated teer machine manufactures go on adding and strengthening security features of Automated teer machine so that customer can carry banking transactions hasse free and without any fear of siphoning of amount from their account and the same frauds works with simiar speed to crack the innovated security feature so that they can have access over the Automated teer machine to expoit the accounts of bank customers. Today banking system is changing and innovating for quick and safe transactions at minimum cost and the banking sector is in no way eft behind from the other industries. Automated teer machine is one of such vita instrument for the banking sector to remain in competition, which provides faciity to customer to carry their banking operations not ony beyond the bank premises and banking hours but aso to transact anywhere in the word that too in oca currency, where the cients makes the transactions. Banks started Automated teer machine as sef-service terminas to primariy withdraw money. Main objective of Automated teer machine was to suppy higher service to the shoppers and ower the banks vaue. Automated teer machine eements cut back per unit transaction cost, supports innovation, produce new service
2 Anaysis of Security Issues of ATM 123 opportunities and increase fexibiity and quaity eves of product and services. At the same time however, financia institutions and their Automated teer machine are becoming more vunerabe to simiar security-reated attacks as known from the reguar computing environment. This can be particuary of concern in an exceedingy ever-changing context wherever Automated teer machines were owned by monetary estabishments and put in their premises, in the main on bank branch faciities, to a repacement reaity wherever a ot of and a ot of Automated teer machines are a unit paced off-premises and Automated teer machine acquirer networks area unit a ot of typicay owned and controed by freeance Automated teer machine operators. Automated teer machine crime has become a wordwide issue that faces not soey customers, however conjointy bank operators. Security measures at banks wi pay an essentia, conducive roe in preventing attacks on customers. These measures are essentia importance once considering vunerabiities and faith in civi proceedings and banks shoud meet bound standards so as to make sure safe and secure banking surroundings for his or her customers. Automated teer machine security probems and Automated teer machine fraud probems typicay foow some distinct patterns based mosty upon the situation of the Automated teer machine security attacks or Automated teer machine fraud incidents. Automated teer machine fraud probems within the most haf invove MasterCard fraud and open-end credit fraud. During the first to midde 1970 s, the primary recognizaby trendy Automated teer machine were put in within the United Kingdom of Great Britain and Northern Ireand and overseas. The magnetic strip card was introduced at this point, and card standards were united through the American Bankers Association that area unit sti in effective these days. Because of the issues encountered with ATM card forgers, banks tried to cipher the PIN on the cardboard, or derive it from the account range, or offer another suggests that of checking it, in an exceedingy means that they hoped woudn t be too obvious to criminas and hackers.
3 Anaysis of Security Issues of ATM 124 In fact, if one has got a Barcaycard or Barcay charge card that dates back a coupe of decades, to detect that the primary and fourth digits of your PIN add up to an equivaent because the second and third, or that the primary and third add up to an equivaent because the second and fourth. However this kind of security wasn t abundant sensibe against a bright forger, and this brings United States to the second contribution that Automated teer machine created to aptop science and thus fostered industria deveopment of cryptography, that is that the study of codes and ciphers. Automated teer machine security attacks invoving physica attacks against the Automated teer machine security encosure area unit wide unfod. Automated teer machine exposive attacks is today very Europe, Austraia and African countries. The study on the trends of attacks on Automated teer machine in various regions sha be taken separatey. Automated teer machine ram raid incidents conjointy occur gobay however area unit most rife within the United States may be partiay thanks to the biggest range of Automated teer machines depoyed in soft-target ocations ike convenience stores. Today s Automated teer machines have become pretty vunerabe. Severa of them use in operation systems ike Microsoft Windows. Around majority of security incidents occur on Windows systems and use IP networks as their communication mechanism. This exposes the system to high security risks thanks to the abundant vunerabiity in open systems of this sort, and that they are iabe to maware infection. There ought to be a necessity of some dominant system that ought to customize for monetary sef-service systems, enabing a centraized check to be unbroken of that appications are a unit run on the system, that native or remote resources area unit accessed and that different
4 Anaysis of Security Issues of ATM 125 system area unit communicated with. By suggesting that of this sort of management package ensures a high security Automated teer machine surroundings isoating at suppy any infection by viruses, Trojan horses, worms or different maware, whereas conjointy preventing any maicious package from being entered or run with access to sensitive Automated teer machines resources. Every Automated teer machines during which this sort of package fitted has associate degree Access management List (ACL) giving an associate degree compete definition of the processes, system resources (fies and ibraries) and permissibe communications. The other part not showing on this ist ought to be mechanicay bocked. Automated teer machines security provided by the banks to safeguard the Automated teer machine. The major security risks of Automated teer machines can be grouped broady in four divisions: I. Physica Security II. Software/Package Security III. Logica Security IV. Communication Security 4.2 PHYSICAL SECURITY: Automated teer machines is amost a direct currency dispenser termina permitting the cient to directy get the money, however a whie thanks to ack of security in some way or the other, some unauthorized user or hackers or criminas take an opportunity to tamper the machine and stea the money by physica attacks on Automated teer machines and by tampering with the machine, cutting the safe, bombing, shouder surfing, ram riding are the other common abuse of
5 Anaysis of Security Issues of ATM 126 Automated teer machines by the frauds. There are severa crimina attacks on Automated teer machines invoving hod-up, remova of Automated teer machines from its premises by force, or by assaut to the Automated teer machines within the premises with safe-breaking instrumentay or by exposives. In the majority of attempts of attacks, the crimina has gained success of varying degree. To safeguard from this sort of frauds some security features are being added/created for Automated teer machines from time to time but these security features gets hoed by the criminas. LOCKS FOR ENTRY IN ATM KISOKS The first security feature a customer comes across before operating an Automated teer machine is digita ock at the entrance of Automated teer machine housing or kiosks. The door aows the customer to open the door ony after inserting ATM card into designated sot. However these doors do not require card to insert whie eaving the Automated teer machine kiosks as door can be opened by puing inside. Though these features have been added to restrict unauthorized person from entering the Automated teer machine kiosks, but importance in imparting security to the machine is imited as an wanted guest can aways enter through Automated teer machine kiosks door in time gap of cosing the door of a genuine ATM card hoder or may enter whie a cient is eaving the Automated teer machines after competing his transactions. Normay there are more than one Automated teer machine instaed in an Automated teer machine kiosk and thereby numbers of both genuine and fake customer may be found at any moment in Automated teer machine kiosks. Presence of arge number person inside kiosks enhances physica security threat to the Automated teer machines
6 Anaysis of Security Issues of ATM 127 Figure 4.1 digita ock at ATM kiosk door. The door ocks of Automated teer machine kiosks having one or more machine have been considered to aow ony genuine ATM card hoders entry into the kiosks, the digita ocks cannot restrict the entry by use of fake/coned ATM cards. These door digita ocks are aso misused some times by frauds by instaing card reader device which can send the detais of ATM cards inserted in it. EXTORTIONS INSIDE ATM KIOSKS. Wayside cheaters and gangster used to oot money from victims at deserted/isoated paces by nabbing the passerby, with introduction of Automated teer machine, they did find sma money or no money from the victims. Since they noticed that invariaby a the victims had ATM cards
7 Anaysis of Security Issues of ATM 128 with them, they added the practice of forced withdrawa from the victims from ATM cards. Gangster either wait in Automated teer machine kiosks for the victim as if they are waiting to withdraw the money or nab a victim at deserted pace and bring the victims to Automated teer machine kiosks and force the victim at knife point or gunpoint to use his ATM card and withdraw the money from the Automated teer machine using ATM card and his PIN number. Figure 4.2 Attack in ATM housing PHYSICAL SECURIRTY THREASTS TO ATMs Initiay Automated teer machine were introduced by the banks and its transactions were imited to the same bank by connecting through computer system of the bank having account detais of its customer and therefore it was not paced at much distant from the bank. But with sharing of transactions on Automated teer machine by host of bank apart from the bank to
8 Anaysis of Security Issues of ATM 129 whom Automated teer machine beongs has ed to situation where Automated teer machines are being at any pace which is convenient to its customer/cients. Instaation of kiosks in Ma/ shoping centre have become common apart from other paces such busy market intersections, hospitas, raiway stations, bus stands, air port and a host of other paces where the bank thinks that Automated teer machine sha be abe to fetch good business. The Automated teer machine instaed within cosed area of a bank or shops/ma are amost secure from the point that thieves or frauds cannot operate in crowded pace and where otherwise aso security arrangement exits on reguar basis and therefore can be rated as highy secured Automated teer machines. The Automated teer machines instaed within the premises of bank or Shoping Ma can be categorized in the security zone next the Automated teer machines paced within banks/ Shopping Ma, as it has be ooked after the agencies entrusted for the security of the bank/ shoping ma. The figure 4.3 is an iustration of an Automated teer machine paced by a bank within its premises but outside its banking area. Figure 4.3 ATM in bank premises
9 Anaysis of Security Issues of ATM 130 The Automated teer machine instaed in kiosks to cater the demand of cients by being paced on the spot highy frequented by the cients/users but isoated pace are prone to its misuse by thieves for forced transactions.these Automated teer itsef can be disengaged from its pace of instaations and carried way to convenient pace for break opening of its money chest as iustrated beow: Figure 4.4 Decamping of ATM The concentrate of this approach is to stop physica attack on the Automated teer machines can be achieved in 2 ways that a. By victimization dispenser mechanism that creates it troubesome to retrieve cash whie not correct authority. b. The second way is to use of dye markers and smoke canisters that stop the empoyment of the money within the machine by a thief.
10 Anaysis of Security Issues of ATM 131 HARDWARE SECURITY FOR MANUFACTURER: There are a unit some standard area unit deveoped by totay different nations against that Automated teer machines wi be factory-made with interference of physica attacks. These standards are a unit as foows : American Underwriting Laboratories UL291 Leve one and Leve a pair of Standards, French RMET15 and RMET30 eves, CS, C1, C2 eves Nordic customary INSTA 612 German RAL626/3 customary Automated teer machines safes that go with these standards need totay different eves of resistance against hand toos, eectrica toos, and therma toos. The INSTA customary conjointy needs resistance against exposive attack. UL291 CUSTOMARY FOR ATM SECURITY: Most of the Automated teer machines have unit of 2 forms of safes or security cupboards for securing cash. One sort of Automated teer machines safe is that the Business Hours (BH) safe and aso the different the twenty four Hours Leve one safe. Each safes have to be compeed to meet the UL 291 security customary designed by Underwriters Laboratories, associate degree freeance product-safety testing company. This customary needs that the Automated teer machines manufacturer must suppy a degree of protection against unauthorized remova of currency and aso the remova or manipuation of deaing records. In different words, Automated teer machines with either sort of safe shoud stand up to attacks from somebody attempting to rob cash or amendment the deaing records. Each sort of Automated teer machines safes must be abe standby in environmenta and endurance needs.
11 Anaysis of Security Issues of ATM 132 ATMs SECURITIES (i) BUSINESS HOURS ATM MACHINE An Automated teer machines with a Business Hours safe is meant to store money soey throughout business hours under the watchfu eye of an accountabe owner, manager, or worker. The money hod on during this sort of safe ought to be removed at the shot of the business day. The meta of the Business Hours Automated teer machines shoud stand up to a physica attack from a steaer armed with wires, ines, chises, pry bars, or wrenches for a minimum of 5 minutes. This provides enough time for the shop owner, manager, or worker to make a decision and ca the poice. Business-hour Automated teer machines must meet the UL 291 standards and Automated teer machines shoud typicay weighs around one hundred twenty five metric weight unit. (ii) TWENTY FOUR HOURS LEVELS ATM MACHINE Automated teer machines with Leve one have one safe unit designed to be used twenty four hours every day and shoud weigh around 250 metric weight units and may hod money unattended. The stee of the one safe shoud withstand physica pressure of fifty thousand psi. This sort of Automated teer machines are meant to face up to higher degree of attack, victimization fishing, trapping, and forcing techniques, on the currency instrumentaity from the cient access pane for east haf-hour. Attacks on different parts of the safe, victimization picks and moveabe eectrica toos ike dris and grinders wi be resisted by this sort of safe for up to fifteen minutes. A of our Automated teer machines modes have the Automated teer machines safe is separated from the cient access pane space, that is an additiona security feature that creates Automated teer machines fraud and theft that far more troubesome and difficut.
12 Anaysis of Security Issues of ATM 133 (B) ENVIRONMENTAL NEEDS A Automated teer machines have to be compeed to stand up to eighty five percent humidness for twenty-four hours. This ensures that each one of Automated teer machine maintains records and aso the quaity of the currency within the automatic teer machine. Severa existing Automated teer machines incorporate a security to meet the guideines as aid down by the American Underwriters Laboratories UL291 customary Leve one. This needs that associate degree Automated teer machines safe resists attack by common hand toos soey. The quaity conjointy needs that the safe be made of 1» stee pate to the body and door or of a coth giving equivaent protection to 1» stee pate. Underwriters Laboratories have accepted that ½» high tensie pate which can accord with this demand and variety of Automated teer machines safes is factory-made of such materia. However UL291 Leve one customary does not provide fu protection against force attack ike wedging of the door or associate degree attack on the door or body victimization ange grinders and no protection against exposive or attack by eement cutting instrumentaity. (C) MECHANICAL/COMBINATIONAL LOCKS FOR PHYSICAL SECURITY: To protect the Automated teer machines from physica attacks, mechanica or combination ocks are a unit used wherever in their area unit 2 sets of mechanica ocks and Automated teer machines opens ony if each the ock opened propery with 2 separate keys i.e. there is a mixture of 2 ocks contro to open the money container with this sort of ock. It stops the Automated teer machines from in house worker attacks if any banking officia wi perform a fraud it stop the system. (D) TIME/TIME DELAY LOCK: Lock providing time protection associate degree/or time deay faciities can enhance the protection of an Automated teer machines safe by providing a deterrent to hod-up.
13 Anaysis of Security Issues of ATM 134 (E) CLOSED CIRCUIT TV (CCTV): Strategicay sited cameras wi offer continuing poice investigation (ocay or from an overseas observation Centre) of the approaches to the Automated teer machines. They conjointy offer a hepfu visua deterrent. Recorder empoyed in conjunction with the cameras wi record events endessy or once activated by movement detectors. A nationa egisation regarding the empoyment of CCTV ought to be discovered. (F) ATM CLADDING Reinforcement panes wi be fitted to hide the door associate degrees one or a ot of body sites of an Automated teer machines safe to extend resistance to physica attack. The panes conjointy defend the present protection system which might be increased by upgraded bot work, strap work and hinge protection. (G) LINE UPS To prevent customers from shouder surfboarding banks create barricades before the Automated teer machines to outine the road up positions for users and restricting the side view of person standing behind the actua user of the Automated teer machine. This sha prevent shouder surfboarding to a greater extent. Beow is that the image shows the road up distance users to safeguard the user input data. Figure 4.5 ine ups for physica security
14 Anaysis of Security Issues of ATM 135 (H) SENSORS EMPLOYED IN ATM SECURITY: In new generations of Automated teer machines, to combat and minimize the Automated teer machines from physica attacks ike cutting, fire, tempering etc. sensor are fitted. New series of Automated teer machines are equipped with heat detector, vibrating detector and tampering detector, which are designed to defend the Automated teer machines from externa attacks and foresta the Automated teer machines from being taken to outside Automated teer machines premises. HEAT SENSOR New Automated teer machines unit are assembed with a heat detector, if an associate degree offender attempt to create a hearth to achieve the money from ATM and ift the firepace is cabin than heat detector activate and ring an aarm for that and start hearth fighting system on. VIBRATION SENSOR Simiar to heat detector, vibration sensor area unit currenty conjointy fixed either within the Automated teer machine or premises housing Automated teer machine. Vibration aarm activates once somebody attempt to cut causing vibration in the Automated teer machine and its premises for taking appropriate actions to defend the Automated teer machine from cutting and foresta the Automated teer machine from any sort of tampering with the machine. The vibration detectors are used in the Automated teer machine, which contains sophisticated signa process anayzer (EVD Exposion Vibration Detector and mechanica device uneash mechanism housed among a sturdy stee encosure. This mix offers are refined to attack detection of associate degrees by controed access to the protected unit by an authorized user.
15 Anaysis of Security Issues of ATM 136 Fig 4.6 Vibration Sensor And Atm Safe The above figure 4.6 shows the ATM and its companion magnet hasp, the atter is fitted to the forefront of the door. Once the door is cosed the magnet is hidden beow the id of the Automated teer machine and door standing wi be monitored. To permit access to the safe, a ow-tension DC offer is appied to the Automated teer machine indicated by an inexperienced junction rectifier. The icensed user presses the discharge switch and aso the id of the ATM8 wi be opened (imited trave) thereby reeasing the magnet and permitting the safe door to be opened. Additionay to twin anti-tamper protection (singe output), the ATM8 offers variety of further outputs : VIBRATION. Attack by means of grinding, hammering, driing, or therma cutting device can trigger the VIB output. IMPACT. Exposives, a series of consistent strikes or makes an attempt at ram-raid can activate the IMP output instanty.
16 Anaysis of Security Issues of ATM 137 TILT. Any decide to move the protected instrumentaity can activate the ean output. Additionay, high-energy attacks ike ATM ram-raid aso wi trigger this output. DOOR. A votage-free contact that reports the state of the safe door. SLIDE. A votage-free contact indicating if the Automated teer machine cow is opened/ cosed. The principe to operate vibration aarm system of the Automated teer machine is signa processing and anaysis of the assorted on-board sensors then to require acceptabe action within the event of a egitimate attack. Additionay, this unit features a range of dedicated inputs that support remote sensors that enhance and extend the word of coverage. VIBRATION SENSOR Aarm system based on vibration sensor is based on sensing increase in vibration eve which might woud have occurred due equipments depoyed for forced remova of the Automated teer machine or attempt to damage the safe of the Automated teer machine to oot the cash kept in Automated teer machine. Any attempt to harm the Automated teer machine physicay by any mechanica means sha generate vibration much above the norma eve of noise in Automated teer machine kiosks and it this increase in eve of vibration which is needed to be sensed for raising the aarm and activating the aarm at poice contro room and the bank office. A vibration sensor caed Shear mode acceerometer designs feature on sensing crystas attached between a centre post and a seismic mass. A compression ring or studsare appied as pre-oad force to the eement assemby to insure a rigid structure and inear behaviour. Under acceeration, the mass causes a shear stress to be appied to the sensing crystas. This stress resuts in a proportiona eectrica output by the piezoeectric materia. The output is coected by eectrodes and transmitted by ightweight ead wires to either the buit-in signa conditioning circuitry of ICP sensors, or directy to the eectrica connector for charge mode types.
17 Anaysis of Security Issues of ATM 138 Figure 4.7 vibration aarm The sensing crystas are isoated from the base and housing. Shear mode acceerometers rejects therma transient and base-bending effects to a arger extent. The shear geometry aows itsef to end to sma size to promote high frequency in the response whie minimizing mass oading effects on the test structure. With combination of idea characteristics, shear mode acceerometers normay offer optimum performance to meet the requirement. SELECTION OF AN ACCELEROMETER : Seection of the best acceerometer for specific predictive maintenance appication is difficut, even for the most seasoned of engineers/technicians. Typicay, the process the best suited acceerometer can be chosen by examining or fitered down to a series of quaifying questions reated to actua requirement for a particuar purpose, in this case to have scope to defend the Automated teer machine from burgar who is attempting to cut the Automated teer machine from its instaation for breaking upon its chest to decamp with money stashed inside i.e.
18 Anaysis of Security Issues of ATM 139 acceerometer needs to be activated when the sound eve increases in an Automated teer machine from its norma working eve to noise of cutting the meta pates by meta cutter or eectric cutter or gas cutters as noise eve of these cutting device is much higher than the norma eve for generaized Automated teer machine operation for conducting financia transactions. This might seem obvious at first in seecting acceerometer is the step to actua vibration present in an Automated teer machine by measuring and aso measuring the eve of vibration whie disodging an Automated teer machine from its pedestas i.e. determining the goas. Vibration can be monitored with acceerometers that provide raw vibration data or transmitters that provide the cacuated overa root mean square (RMS) vibration. Anaysts find raw vibration readings to be usefu because they contain a the information in the vibration signa. The true peak ampitudes and vibration frequencies may be avaiabe. The overa RMS or peak vaues are usefu in contro systems such as PLC, DCS. SCADA and PI because of their continuous 4-20mA signa and some appications use both. By determining signa variety is required for the appication significanty narrows the search of equipment required. Vibration has to be measured in terms of acceeration, veocity or dispacement. Some industria sensors measure variation in temperature aong with vibration. Finay, some appications, such as vertica pumps, are best monitored in more than one vibration axis in which case does the appication require singe, biaxia or triaxia measurement. There are two main differences between ow-cost and precision acceerometers. First, precision units typicay receive a fu caibration, that is, the sensitivity response is potted with respect to the usabe frequency range. Low cost acceerometers receive a singe-point caibration and the sensitivity is shown ony at a singe frequency. Second, precision acceerometers have tighter toerances on some specifications such as sensitivity and frequency range. For exampe, a precision acceerometer might have a nomina sensitivity of 100mV/g ± 5% (95 to 105mV/g) (see Figure 1) whie a ow-cost acceerometer might have a sensitivity of
19 Anaysis of Security Issues of ATM mV/g ± 10 % (90 to 110mV/g). Customers with data acquisition systems wi often normaise the inputs with respect to the caibrated sensitivity. This aows a group of ow cost sensors to provide accurate, repeatabe data. Regarding frequency, a precision acceerometer typicay has frequency ranges in which the maximum deviation is 5% whie ow-cost sensors frequency might offer a 3dB frequency band. Even so, a ow cost sensor might offer exceent frequency response. The maximum ampitude or range of the vibration being measured determines the sensor range that can be used. Typica acceerometer sensitivities are 100mV/g for a standard appication (50g range) and 500mV/g for a ow-frequency or ow-ampitude appication (10g range). Genera industria appications with 4-20mA transmitters commony use a range of 0-25mm; s or 0-50mm/s. Physica structures and dynamic systems respond differenty to varying excitation frequencies. A vibration sensor is no different. Piezoeectric materias, by nature, act as high pass fiters and as a resut, even the best piezoeectric sensor wi have a ow-frequency imit near 0.2Hz. A ranges in which the maximum deviation is 5% whie ow-cost sensors might offer a 3dB frequency band. Even so, a ow cost sensor might offer exceent frequency response. The maximum ampitude or range of the vibration being measured determines the sensor range that can be used. Typica acceerometer sensitivities are 100mV/g for a standard appication (50g range) and 500mV/g for a ow-frequency or ow-ampitude appication (10g range). Genera industria appications with 4-20mA transmitters commony use a range of 0-25mm; s or 0-50mm/s. Physica structures and dynamic systems respond differenty to varying excitation frequencies. A vibration sensor is no different. Piezoeectric materias, by nature, act as high pass fiters and as a resut, even the best piezoeectric sensor wi have a ow-frequency imit near 0.2Hz. A sensor that acts as a dynamic system with one degree of freedom exhibits natura frequencies. The signa is greaty ampified at the natura frequency, eading to significant change in sensitivity and possibe saturation. Most industria acceerometers have singe or
20 Anaysis of Security Issues of ATM 141 doube-poe RC fiters to combat saturation excitation at the resonant frequency. Thus it is critica to seect a sensor with a usabe frequency range that incudes every frequency of interest. Appications with extremey high temperatures can pose a threat to the eectronics buit into acceerometers and 4-20mA transmitters, Charge-mode acceerometers are avaiabe for use in very high temperature appications. These have no buit-in eectronics, but instead have remote charge ampifiers. Charge-mode acceerometers with integra hard ine cabe are avaiabe for appications hotter than 260 C, such as gas turbine vibration monitoring. Industria acceerometers with integra poyurethane cabe can be competey immersed in iquid for permanent instaation. For high-pressure appications, it is a good idea to test the sensors at pressure for one hour. An integra cabe is aso normay required if the appication is sprayed rather than being competey immersed, such as cutting fuid on machine toos. Industria acceerometers can be constructed with corrosion and chemica resistant stainess stee bodies. Consider using PTFE cabe with corrosion resistant boot connectors if the appication is in an environment with harmfu chemicas. Consuting a chemica compatibiity chart is strongy recommended for any suspect chemicas. Integra armour-jacketed cabes offer exceent protection for cabes that might come into contact with debris such as cutting chips or worker s toos. Utimatey, the sensor wi need to be instaed on equipment in convenient position. However, sensor geometry has itte effect on its performance, but factors such as the space avaiabe and positioning that ensures that a maintenance engineer can gain safe access, do need to be taken into account. Acceerometers and 4-2OmA transmitters are both avaiabe with CSA and ATEX approvas for use in hazardous areas. Compare the type of approva needed with the sensor s pubished approvas to ensure it meets requirements. SENSOR TECHNOLOGY FOR SENSING VIBRATION: It is aso worth to consider to specify a shear or compression technoogy sensor before choosing one for specific purpose. This question coud command an artice a of its own but in essence,