Who are Humex? SOUND SUPPRESSION ADVANTAGES PAGE TWO E: PAGE FIFTEEN

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2 Humex Exhaust Control are leading manufacturers suppliers of noise gas pollution. Humex has a reputation engineering excellence our products are designed manufactured to the highest stards. Our products include various grades of mufflers silencers power generating sets, lighting plants, mining earth moving machinery. We are specialists in diesel gas engine exhaust system design, manufacture installation. Our range of sound suppression silencers offer reductions of up to to 40dBA. These silencers are suitable application to inlet discharge emissions from Diesel gas engines, Turbines compressors are available with integrated diesel oxidation catalysts particulate filters where required. Critical level exhaust silencers, piping, bellows mounting systems power generating installations, mining earth moving machinery used SOUND SUPPRESSION ADVANTAGES Humex works very closely with the mining/ heavy duty industry, site managers with all relevant health safety personnel to ensure that all manufactured installed equipment creates the healthiest safest environment possible your team. existing exhaust system the installation of the new exhaust systems sound suppression kits. Complete range or emission control solutions reduction of CO,HC, NOx Silencers with inbuilt in-built diesel purifiers particulate filters gensets, mining, construction road transport materials hling applications. Spark arresting silencers on off road machinery to AS1019. Manufacture installation or thermal blankets installation all types of machinery including gensets, marine underground mining machinery. Exhaust silencers rail marine including custom fabrication in various grades of aluminum, stain-less mild steel. Our highly successful exhaust attenuation of haul trucks, scrapers, loaders, dozers excavators. Predominantly work has been completed utilizing existing space within the engine bay, with minimal or no change Double walled pipes thermal reduction increased durability. Humex also offers a full CAD design service, whereby we can adapt our stard range of silencers to meet specific installation requirements. This is particularly useful earthmoving mining applications where space within the machine engine bay may be restricted. Our highly successful exhaust attenuation packages includes system many models of haul trucks, scrapers, loaders, dozers excavators. Predominantly work has been completed utilizing existing space within the engine bay, with minimal Manufacture installation of thermal blanket insulation all types of underground mining applications. PAGE TWO E: SALES@HUMEXEXHAUSTCONTROL.COM PAGE FIFTEEN

3 SOUND SUPPRESSION ADVANTAGES Humex Exhaust Control are leading manufacturers suppliers of The Humex business model involves total concept, custom design, heavy duty quality of noise gas pollution. Humex has a reputation engineering product, installation fast response to achieve excellence our products are designed manufactured to the the optimum solutions. We believe in offering our highest stards. Our products include various grades of mufflers customers a complete solution, rather than simply silencers power generating sets, lighting plants, mining offering supply of catalogue items, so that the earth moving machinery. We are specialists in diesel gas engine end result will last years to come. exhaust system design, manufacture installation. Our range of silencers are suitable application to inlet discharge emissions from Diesel gas engines, Turbines compressors are available with integrated diesel oxidation catalysts particulate filters where required. Humex offers a full custom CAD design service, whereby we can adapt our stard range of silencers to meet specific installation requirements. Critical level exhaust silencers, piping, bellows This is mounting particularly systems useful power earth moving generating installations, mining earth mining moving applications machinery where used space within the machine engine bay may be restricted. Complete range or emission control solutions reduction of CO,HC, NOx Silencers with in-built diesel purifiers particulate filters gensets, mining, construction road transport materials hling Humex applications. offers tube bending cutting, precision welding roll ming, exping, Spark arresting silencers on off road machinery to AS1019. notching press/die ming, roll beading Manufacture installation or thermal blankets installation dimpling, plasma all types cutting, of machinery mild, stainless including gensets, marine underground mining aluminized machinery. tubing, explosive proof silencers indeed many other solutions. Exhaust silencers rail marine including custom fabrication in various grades of aluminum, stain-less mild steel. Double walled pipes thermal reduction increased durability. Humex also offers a full CAD design service, whereby Our Exhaust we can adapt attenuation our stard packages range of silencers to meet specific installation requirements. This is particularly come complete useful as earth a kit moving with all mining applications where space within the machine engine bay may be required restricted. accessories Our highly ensuring successful ease exhaust of attenua-tion packages includes system many models of haul fitment trucks, scrapers, ease of mind. loaders, dozers excavators. Predominantly work has been completed utilizing existing space within the engine bay, with minimal SOUND SUPPRESSION WHAT ADVANTAGES IS SOUND SUPPRESSION? The exhaust systems on machines/vehicles have many varied designs. These sometimes have inherent designs or have the need to be altered to accommodate the need Noise reductions recommended Humex works very closely with the mining/ the machine by deed or by personnel. There are many heavy areas duty that industry, need to site be managers looked at when with seeking all to suppress noise by altering or changing the exhaust relevant system. health When silencing safety elements personnel are to ensure inserted into an exhaust system there is an Insertion Loss (IL).Insertion that all Loss manufactured is defined as the installed reduction equipment of noise level creates the healthiest safest environment that occurs when a silencing element is inserted into the system. Because engines generate strong tonal possible your team. components, the IL of any one muffler will not be the same with different engines, different loads, or different piping configurations. Engine noise varies significantly with Loading. Typically the noise level at full load is about 10 dba higher than the no-load condition. The majority of the engine noise is at low frequencies. The Overall noise from most un-silenced engine exhaust systems vary from about 110dBA to 120 dba Humex, when offers measured on-site service 1 meter of from the removal the pipe of outlet. the Exhaust noise can also be affected by engine turbo existing charges exhaust after system coolers. the Humex installation always of obtains the new exhaust systems sound suppression kits. exhaust noise data from the engine manufacturers bee any system is designed. The most common element used to silences exhaust systems are reactive mufflers. Reactive mufflers are available in a wide ranges of dimensions. The noise is reduced by cing the exhaust air to pass through a series of tubes chambers. Each element in the muffler has sound reduction properties Our highly that vary successful greatly with acoustic frequency, it is the mixing matching exhaust of attenuation these elements that packages include systems constitutes muffler design what constitutes a sound suppression kit. Normally many models of haul the higher Insertion Loss mufflers will be physically larger than the lower quality trucks, scrapers, loaders, units. dozers excavators. Predominantly work has The first step in designing a suppression kit to replace a stard system is to underst the project requirements. In this process we always obtain the silenced noise levels from the engine manufacturers. This is typically given as un- a sound pressure level at 1 meter or similar distance. We then determine the noise criteria at the receiver. The next step is to calculate Manufacture the un-silenced exhaust noise at the receiver location. The next step is to calculate installation the of insertion thermal loss s of the muffler by subtracting the receiver noise criteria from blanket the insulation un-silenced receiver all types of machinery noise level. Once this is completed the exhaust system is designed to reduce the stard exhaust system by the required dba reduction sought. PAGE FOURTEEN E: SALES@HUMEXEXHAUSTCONTROL.COM PAGE THREE

4 SOUND 785 SUPPRESSION DUMP TRUCK ADVANTAGES SOUND SUPPRESSION Humex Exhaust Control are leading manufacturers suppliers of noise gas pollution. Humex has a reputation engineering excellence our products are designed manufactured to the highest stards. Our prod-ucts include various grades of mufflers silencers power generating sets, lighting plants, mining earth moving machinery. We are specialists in diesel gas engine exhaust system design, manufacture installation. Our range of WHAT IS NOISE? silencers are suitable application to inlet discharge emissions from Noise is typically defined as unwanted sound, sound being the human sensation of pressure fluctuations Diesel gas engines, Turbines compressors are available with in the air. Sound levels are expressed in decibels (db) on a logarithmic scale, where 0dB is nominally the integrated diesel oxidation catalysts particulate filters where required. threshold of hearing 120dB is nominally the threshold of pain. Depending upon the circumstances characteristics of the sound in question, a change in level of 3dB is just perceptible, Critical level whereas exhaust an silencers, increase piping of 10dB, bellows is perceived mounting as a subjective systems doubling power of loudness (as noise is measured generating on a installations, logarithmic scale). mining earth moving machinery used The frequency of sound is the rate at which a sound wave oscillates, is expressed in Hertz (Hz). The Complete range or emission control solutions reduction of CO,HC, NOx frequency of a sound produces it s distinctive tone. The rumble of distant thunder has a low frequency, while a whistle has a high frequency. The normal range of hearing a healthy young person extends from Silencers approximately with in-built 20 Hz diesel up to purifiers Hz (or particulate 20 khz) filters while the gensets, range from mining, the lowest to highest note of a piano construction is 27,5 road Hz to transport 4186 Hz. The materials sensitivity hling of the human applications. ear to different frequencies in the audible range is not unim. For example, hearing sensitivity decreases markedly as frequency falls below 250Hz. Spark arresting silencers on off road machinery to AS1019. A mechanism Manufacture known as installation A-weighting or thermal has been blankets adopted installation in order to all account types of machinery this non-linearity of the human including ear. Sound gensets, levels marine expressed underground using A-weighting mining are machinery. typically denoted dba. Noise Exhaust levels are silencers usually assessed rail in marine terms including of A-weighted custom decibels fabrication dba. in If you various have grades to shout of aluminum, to get yourself heard stain-less the background mild noise steel. level is 75-80dBA. An average living room would typically have a noise level of about 40dB(A) while busy road traffic would generate about 70-80dB(A) measured on the pavement Double walled pipes thermal reduction increased durability. (approx. 3m from the vehicles). The study of sound is called acoustics covers all fields of sound production, sound propagation Humex sound also reception, offers a full whether CAD design created service, received whereby by we human can adapt beings our or stard by machines range of silencers measuring to instruments. meet specific Noise installation generally requirements. radiates in This all directions, is particularly but can useful bend earth around moving over mining walls applications buildings where can space reflect within back from the machine solid surfaces. engine Significantly bay may be careful restricted. positioning Our highly of noisy successful plant exhaust equipment attenuation can packages includes system many models of haul trucks, scrapers, loaders, dozers excavators. be very effective in reducing noise levels. Predominantly work has been completed utilizing existing space within the engine bay, with minimal Installation of Sound Suppression System Humex works very closely with the mining/ heavy duty industry, site managers with all relevant health safety personnel to ensure that all manufactured installed equipment creates the healthiest safest environment possible your team. existing exhaust system the installation of the new exhaust systems sound suppression kits. Our highly successful exhaust attenuation of haul trucks, scrapers, loaders, dozers excavators. Predominantly work has been completed utilizing existing space within the engine bay, with minimal or no change Manufacture installation of thermal blanket insulation all types of underground mining applications. PAGE FOUR E: SALES@HUMEXEXHAUSTCONTROL.COM PAGE THIRTEEN

5 SOUND 785 SUPPRESSION DUMP TRUCK ADVANTAGES SOUND SUPPRESSION HUMEX EXHAUST Humex Exhaust Control are leading manufacturers suppliers of noise gas pollution. Humex has a reputation engineering excellence our products are designed manufactured to the highest stards. Our products include various grades of mufflers silencers power generating sets, lighting plants, mining earth moving machinery. We are specialists in diesel gas engine exhaust system design, manufacture installation. Our range of silencers are suitable application to inlet discharge emissions from Diesel gas engines, Turbines compressors are available with integrated diesel oxidation catalysts particulate filters where required. Removal of old system Critical level exhaust silencers, piping, bellows existing including mounting exhaust systems all pipework power the installation of the generating installations, mining earth new moving exhaust machinery systems used sound suppression kits. Complete range or emission control solutions reduction of CO,HC, NOx An indication of the level of some common sounds is shown below: Silencers with in-built diesel purifiers particulate filters gensets, mining, construction road transport materials hling Our highly applications. successful exhaust attenuation Spark arresting silencers on off road machinery of haul trucks, to AS1019. scrapers, loaders, dozers excavators. Predominantly work has been Manufacture installation or thermal blankets completed installation utilizing all existing types of space machinery within the including gensets, marine underground mining engine machinery. bay, with minimal or no change Exhaust silencers rail marine including custom fabrication in various grades of aluminum, stain-less mild steel. Double walled pipes thermal reduction increased durability. Humex also offers a full CAD design service, whereby Manufacture we can adapt installation our stard of thermal range of silencers to meet specific installation requirements. This is particularly blanket useful insulation earth all moving types of mining applications where space within the machine engine bay may be machinery restricted. including Our highly gensets, successful marine exhaust attenuation packages includes system many models of haul trucks, underground scrapers, mining loaders, applications. dozers excavators. Predominantly work has been completed utilizing existing space within the engine bay, with minimal OCCUPATIONAL NOISE It is well established that prolonged exposure to high noise levels can result in permanent irreversible damage to hearing. It is also recognized that the only effective preventative measure is to control noise exposure bee hearing loss occurs. Noise induced or occupational deafness involves regular exposure to noise over a long period with gradually acquired sensory-neural hearing loss damage to the inner ear nerve pathways to the brain. Acoustic trauma involves exposure to a very high noise level over a short period such as an explosion perating the eardrum. 40 out of every 100 workers who have worked all their lives at high noise levels (>90db9A) will at the age of 65 years find it difficult to hear other people talking THIS TYPE OF DEAFNESS IS INCURABLE PAGE TWELVE E: SALES@HUMEXEXHAUSTCONTROL.COM PAGE FIVE

6 Humex Exhaust Control are leading manufacturers suppliers of noise gas pollution. Humex has a reputation engineering excellence our products are designed manufactured to the highest stards. Our products include various grades of mufflers WHAT IS LOW FREQUENCY NOISE? silencers power generating sets, lighting plants, mining earth moving machinery. We are specialists in diesel gas engine exhaust system design, manufacture installation. Our range of silencers are suitable application to inlet discharge emissions from We have defined noise as unwanted sound. We are all aware of the noises that surround us in our everyday lives, Diesel many of gas which engines, are a source Turbines of nuisance. compressors The effect of low are frequency available noise with (LFN), however, is often not recognized integrated as diesel a nuisance, oxidation even catalysts though it may particulate have a profound filters where effect required. on the psychological physiological well being of some people. Sound The frequency of a sound is the number of sound waves which pass a particular point in one second, is Critical measured level in exhaust Hertz (Hz). silencers, Sound piping audible, bellows to the adult mounting human ear systems is in the power range Hz. Low frequency sound may be loosely defined as having a frequency below 150 Hz. Sound in the lower frequency generating installations, mining earth moving machinery used range is around us all the time, but we are not always aware of it as people s sensitivity varies considerably. Problems arise when the levels of low frequency noise are such that they interfere with our everyday lives. Low Frequency Complete range Noise or There emission are many control sources solutions of low frequency reduction noise of CO,HC, which NOx can cause disturbance /or annoyance diesel both particulates indoors power outdoors. generators Sound enters installed buildings below through ground their or in structure, high rise through buildings. open windows, or can be generated inside the building. Sound with a very long wavelength may be heard as noise (primary noise), Silencers cause rattling with in-built windows, diesel doors purifiers or furniture particulate (secondary filters noise), gensets, may mining, be difficult to distinguish from a structural construction vibration. road Both transport of these ms materials of noise hling can cause applications. disturbance, particularly at night. LFN can be more noticeable indoors, which is why it is often associated with disturbed sleep. In the open air other Spark noises arresting such as silencers traffic may on mask the off annoying road machinery low frequencies. to AS1019. Indoors, middle high frequency noise from out-side is reduced because the insulating effect of the building increases with sound frequency. Noises Manufacture from the lower installation frequency bs, or thermal however, blankets may installation remain the same, all types or even of machinery increase - hence rattling windows including etc. Another gensets, problem marine is that underground LFN travels mining further machinery. than higher frequencies, so the source is often difficult to trace. Sleep may be disturbed by the hum of a distant boiler, or the rattle of a window caused by passing Exhaust traffic. silencers rail marine including custom fabrication in various grades of aluminum, stain-less mild steel. Sources The following may all be sources of LFN: Amplified music, pumps, fans, boilers, ventilation plant, foundries blasting/quarrying, road, rail, air traffic mining machinery Double walled pipes thermal reduction increased durability. Effects of Low Frequency Noise A low frequency noise is very often characterized by a hum or rumble. It may be confused Explosion with proof tinnitus silencers (ringing/hissing LNG Engines. the ears with no obvious cause). Health Issues related to Noise Humex also offers a full CAD design service, whereby we can adapt our stard range of silencers to The meet hearing specific sensitivity installation range requirements. of people varies; This is theree particularly people useful who are earth disturbed moving by LFN mining may applications feel isolated if where no one space else is within annoyed the machine by the noise. engine Symptoms bay may of be LFN restricted. annoyance Our are highly those successful associated exhaust with stress. attenuation These include feelings of irritation unease, fatigue, headache, nausea disturbed sleep. packages includes system many models of haul trucks, scrapers, loaders, dozers excavators. It Predominantly is not clear at work what has level been Low completed Frequency utilizing Noise may existing be physically space within damaging; the engine however, bay, the with unpleasant minimal symptoms or no change it can to induce the exhaust are sufficient mounting to cause system. disruption significant social economic penalties to sufferers. SOUND EXAMPLE SUPPRESSION OF PLANT NOISE ADVANTAGES TESTING AND RESULTS This raises the important consideration that noise levels at testing distance (i.e., 16m) are dominated by the mid to high frequencies of non-exhaust components theree only modest (2-3 db) reduction of total sound power level is achievable from the exhaust system Humex alone. works It is very well closely established, with the however, mining/ that these same mid to high frequencies are attenuated by the ground heavy duty surface industry, air site (O2 managers molecular excitation) with all over larger distances. It is this reason that many coal relevant mines have health real time safety monitoring personnel systems to ensure with a lowfrequency cut-off to capture mine hum eliminate that extraneous all manufactured sources at higher installed frequencies. equipment creates the healthiest safest environment As an estimate of noise levels differences between the possible pre- post-test your team. results projected to a distance in the order of 900m - 1km from the source, frequencies up to 500 Hz in Table 1 can be logarithmically added together to give the following values. Test Bee (<630 Hz) After (<630 Hz) Difference (<630 Hz) Stationery: db (A) db (A) 4.8 db Dynamic: db (A) db (A) 5.3 db This total noise level reduction (i.e., with the sound suppressing system fitted) of approximately 5 db is likely existing exhaust system the installation of the to be achieved in practice at a distance in the order of 900m - 1 km from the source (after ground new exhaust systems sound suppression kits. atmospheric absorption have attenuated the mid to higher frequencies from non-exhaust components of the truck) would increase as the distance from the source increases. Our highly successful exhaust attenuation of haul trucks, scrapers, loaders, dozers excavators. Predominantly work has been completed utilizing existing space within the engine bay, with minimal or no change Manufacture installation of thermal blanket insulation all types of underground mining applications. PAGE SIX E: SALES@HUMEXEXHAUSTCONTROL.COM PAGE ELEVEN

7 EXAMPLE OF PLANT NOISE TESTING AND RESULTS Humex Exhaust Control are leading manufacturers suppliers of noise gas pollution. Humex has a reputation engineering excellence our products are designed manufactured to the highest stards. Our products include various grades of mufflers silencers power generating sets, lighting plants, mining earth moving machinery. We are specialists in diesel gas engine exhaust system design, manufacture installation. Our range of silencers are suitable application to inlet discharge emissions from Diesel gas engines, Turbines compressors are available with integrated diesel oxidation catalysts particulate filters where required. Critical level exhaust silencers, piping, bellows mounting systems power generating installations, mining earth moving machinery used Complete range or emission control solutions reduction of CO,HC, NOx Silencers with in-built diesel purifiers particulate filters gensets, mining, construction road transport materials hling applications. Spark arresting silencers on off road machinery to AS1019. Manufacture installation or thermal blankets installation all types of machinery including gensets, marine underground mining machinery. Exhaust silencers rail marine including custom fabrication in various grades of aluminum, stain-less mild steel. SOUND SUPPRESSION HUMEX ADVANTAGES EXHAUST Noise can cause annoyance fatigue, interfere with communication sleep, reduce efficiency damage hearing. Physiological effects of exposure to noise include constriction of blood vessels, tightening Humex works very closely with the mining/ of muscles, increased heart rate blood pressure changes in stomach abdomen movement. The heavy duty industry, site managers with all effects of exposure to noise are personal as hearing sensitivity relevant health varies. Exposure safety to personnel constant or to very ensure loud noise either occupational or leisure can cause temporary that or all permanent manufactured damage to installed hearing. equipment creates the healthiest safest environment There is an increasing body of research linking prolonged exposure to transport noise to health impacts. A possible your team. major impact of noise is sleep disturbance disrupted sleep has been linked to effects on cardiac health. A number of reports have made direct links between transport/machinery noise cardiac health. Nuisance How far low frequency noise presents a serious nuisance problem is uncertain, but it is often a source of irritation. Assessing the level of nuisance caused by low frequency noise is difficult. Ordinary sound level meters may not be able to detect LFN on the decibel scale existing as its exhaust decibel system level is often the lower installation than background of the noise. A narrow b frequency analyzer is required new to exhaust measure systems it. Noise nuisance sound suppression is determined kits. by the magnitude of the noise on the decibel scale. Controlling Low Frequency Noise Apart from the difficulties of tracking down the source of low frequency noise, assessing its magnitude, practical methods of control are technically difficult often prohibitive in cost. Sound proofing in buildings Our highly successful exhaust attenuation is usually impracticable as the design - particularly of modern buildings - can enhance the effect. Enclosing or silencing the noise source is a better option will of provide haul trucks, a more scrapers, comprehensive loaders, dozers solution. This is often difficult expensive as it involves enclosing the source excavators. in a combination Predominantly of massive work has structures been to reduce sound transmission. LFN from machinery can normally completed be reduced utilizing by the existing use of sound space suppression within the silencers engine bay, with minimal or no change pipework. The answer to eliminating low frequency noise lies in the design of the sources themselves... Double walled pipes thermal reduction increased durability. Humex also offers a full CAD design service, whereby we can adapt our stard range of silencers to meet specific installation requirements. This is particularly useful earth moving mining applications where space within the machine engine bay may be restricted. Our highly successful exhaust attenuation packages includes system many models of haul trucks, scrapers, loaders, dozers excavators. The above results circled show significant noise reduction at the lower frequencies (up to 400 Hz) that Predominantly work has been completed utilizing existing space within the engine bay, with minimal are typically dominated by muffler noise. Generally, mid to high frequency noise is dominated by other components of the truck theree are not significantly affected by fitment of the muffler system. Manufacture installation of thermal blanket insulation all types of underground mining applications. PAGE TEN E: SALES@HUMEXEXHAUSTCONTROL.COM PAGE SEVEN

8 EXAMPLE OF PLANT NOISE TESTING AND RESULTS This letter report presents the results of a plant noise testing conducted at a Coal Mine on January Humex Exhaust Control are leading manufacturers suppliers of The purpose of these tests was are to measure the sound power levels (Lw, B(A)) of a CAT 785 rear dump truck (#199) to determine the noise reduction achieved by fitment of a Humex sound suppression noise gas pollution. Humex has a reputation engineering exhaust system. excellence our products are designed manufactured to the highest stards. Our products MONITORING include various grades PROCEDURES of mufflers silencers power generating sets, lighting plants, mining Dynamic testing of the truck in motion was conducted using ISO 6395:2008. The layout of the machinery earth moving machinery. We are specialists in diesel gas engine path of motion measurement points is shown in Figure 1. When applied to dump trucks in motion, the exhaust system design, manufacture installation. Our range of ward measurement path is uphill from point A to point B the reverse path from B to A has the machine travelling down-hill. The truck was loaded both directions of motion. silencers are suitable application to inlet discharge emissions from Diesel gas engines, Turbines compressors are available with integrated diesel oxidation catalysts particulate filters where required. Critical level exhaust silencers, piping, bellows mounting systems power generating installations, mining earth moving machinery used Complete range or emission control solutions reduction of CO,HC, NOx Silencers with in-built diesel purifiers particulate filters gensets, mining, construction road transport materials hling applications. Spark arresting silencers on off road machinery to AS1019. Manufacture installation or thermal blankets installation all types of machinery including gensets, marine underground mining machinery. Exhaust silencers rail marine including custom fabrication in various grades of aluminum, stain-less mild steel. Double walled pipes thermal reduction increased durability. Humex also offers a full CAD design service, whereby we can adapt our stard range of silencers to meet specific installation requirements. This is particularly useful earth moving mining applications where space within the machine engine bay may be restricted. Our highly successful exhaust attenuation packages includes system many models of haul trucks, scrapers, loaders, dozers excavators. Predominantly work has been completed utilizing existing space within the engine bay, with minimal SOUND EXAMPLE SUPPRESSION OF PLANT ADVANTAGES NOISE TESTING AND RESULTS Sound power levels (in third-octave bs) calculated in accordance with the methodologies of AS ISO 6395 are summarized in Table 1, along with the noise level difference achieved after fitment of the sound suppression exhaust system. Third-octave data Humex the works stationary very closely (AS2012) with the test mining/ are presented in Figure 1, with results the dynamic test presented in heavy Figure duty 2. industry, site managers with all relevant health safety personnel to ensure that all manufactured installed equipment TABLE 1 creates the healthiest safest environment MEASURED TRUCK SOUND POWER LEVELS (DB) CAT 785 UNIT #199 (JAN 2011) possible your team. FREQUENCY STATIONARY STATIONARY STATIONARY DYNAMIC DYNAMIC DYNAMIC (HZ) (BEFORE) (AFTER) (DIFFERENCE) (BEFORE) (AFTER) (DIFFERENCE) existing exhaust system the installation of the new 9.4exhaust systems sound suppression kits Our 0.8highly successful 113.6exhaust attenuation of haul trucks, scrapers, loaders, dozers excavators. 1.8 Predominantly work has been completed 1.2 utilizing existing space within the engine bay, with minimal or no change Manufacture 2.7 installation of thermal blanket 3.1 insulation all types of 3.6 underground mining applications , Sum db (A) PAGE EIGHT E: SALES@HUMEXEXHAUSTCONTROL.COM PAGE NINE