[{"data":1,"prerenderedAt":616},["ShallowReactive",2],{"site-footer-common":3,"glossary:eu-directive-2003-10-ec":45,"glossary-related:eu-directive-2003-10-ec":220},{"id":4,"extension":5,"footer":6,"meta":40,"navbar":41,"stem":43,"__hash__":44},"common\u002Fcommon.yml","yml",{"tagline":7,"links":8,"sections":9},"Acoustic cleaning intelligence for industrial fouling, soot, ash, dust and build-up.",[],[10,19,31],{"title":11,"links":12},"Product",[13,16],{"label":14,"to":15},"How it works","\u002F#product",{"label":17,"to":18},"Cost assessment","\u002F#hero",{"title":20,"links":21},"Company",[22,25,28],{"label":23,"to":24},"What we build","\u002F#about",{"label":26,"to":27},"Careers","\u002F#careers",{"label":29,"to":30},"Contact","\u002F#contact",{"title":32,"links":33},"Resources",[34,37],{"label":35,"to":36},"Blog","\u002Fresources\u002Fblog",{"label":38,"to":39},"Glossary","\u002Fglossary",{},{"links":42},[],"common","YocmZRy1AYfBbpgGVms-zhdiABlF8VTxHx6h4rDmZBA",{"id":46,"title":47,"aliases":48,"body":52,"category":201,"description":202,"extension":203,"meta":204,"navigation":205,"path":206,"relatedTerms":207,"seo":211,"sources":214,"stem":218,"term":47,"__hash__":219},"glossary\u002Fglossary\u002Feu-directive-2003-10-ec.md","EU Directive 2003\u002F10\u002FEC",[49,50,51],"2003\u002F10\u002FEC","EU noise directive","Physical Agents (Noise) Directive",{"type":53,"value":54,"toc":194},"minimark",[55,66,88,93,107,111,169,172,176],[56,57,58,61,62,65],"p",{},[59,60,47],"strong",{}," (also called the ",[63,64,51],"em",{},") sets workplace noise-exposure limits across EU Member States. Three thresholds matter:",[67,68,69,76,82],"ul",{},[70,71,72,75],"li",{},[59,73,74],{},"Lower exposure action value"," — 80 dBA daily (Member States must provide hearing protection)",[70,77,78,81],{},[59,79,80],{},"Upper exposure action value"," — 85 dBA daily (must be used, engineering controls considered)",[70,83,84,87],{},[59,85,86],{},"Exposure limit value"," — 87 dBA daily (must not be exceeded, even with hearing protection)",[89,90,92],"h2",{"id":91},"industrial-sonic-horn-implications","Industrial sonic-horn implications",[56,94,95,96,101,102,106],{},"The directive applies to all EU industrial workplaces. Workplaces with installed ",[97,98,100],"a",{"href":99},"\u002Fglossary\u002Fsonic-horn","sonic horns"," must conduct noise-risk assessments, often deploying ",[97,103,105],{"href":104},"\u002Fglossary\u002Fsound-attenuation-enclosure-sonic-horn","sound-attenuation enclosures",", implementing operator-distance restrictions during horn firing, and requiring hearing protection in adjacent areas.",[89,108,110],{"id":109},"comparison-with-us-osha","Comparison with US OSHA",[112,113,114,133],"table",{},[115,116,117],"thead",{},[118,119,120,124,127],"tr",{},[121,122,123],"th",{},"Threshold",[121,125,126],{},"EU 2003\u002F10\u002FEC",[121,128,129],{},[97,130,132],{"href":131},"\u002Fglossary\u002Fosha-29-cfr-1910-95","US OSHA 29 CFR 1910.95",[134,135,136,148,159],"tbody",{},[118,137,138,142,145],{},[139,140,141],"td",{},"Lower action",[139,143,144],{},"80 dBA",[139,146,147],{},"—",[118,149,150,153,156],{},[139,151,152],{},"Upper action \u002F PEL",[139,154,155],{},"85 dBA",[139,157,158],{},"90 dBA",[118,160,161,164,167],{},[139,162,163],{},"Exposure limit",[139,165,166],{},"87 dBA",[139,168,147],{},[56,170,171],{},"The EU directive is more stringent than the US OSHA standard in absolute terms, particularly at the upper action level.",[89,173,175],{"id":174},"related-terms","Related terms",[67,177,178,183,189],{},[70,179,180],{},[97,181,182],{"href":131},"OSHA 29 CFR 1910.95",[70,184,185],{},[97,186,188],{"href":187},"\u002Fglossary\u002Fsound-pressure-level","Sound pressure level",[70,190,191],{},[97,192,193],{"href":104},"Sound-attenuation enclosure (sonic horn)",{"title":195,"searchDepth":196,"depth":196,"links":197},"",2,[198,199,200],{"id":91,"depth":196,"text":92},{"id":109,"depth":196,"text":110},{"id":174,"depth":196,"text":175},"standards-regulations","EU Directive 2003\u002F10\u002FEC (also called the Physical Agents (Noise) Directive) sets workplace noise-exposure limits across EU Member States. Three thresholds matter:","md",{},true,"\u002Fglossary\u002Feu-directive-2003-10-ec",[208,209,210],"osha-29-cfr-1910-95","sound-pressure-level","sound-attenuation-enclosure-sonic-horn",{"title":212,"description":213},"EU Directive 2003\u002F10\u002FEC — workplace noise exposure rules","EU Directive 2003\u002F10\u002FEC sets noise-exposure limits for EU workplaces. Lower action 80 dBA, upper action 85 dBA, exposure limit 87 dBA, all daily averages.",[215],{"title":216,"url":217},"EUR-Lex — Directive 2003\u002F10\u002FEC","https:\u002F\u002Feur-lex.europa.eu\u002Flegal-content\u002FEN\u002FALL\u002F?uri=CELEX:32003L0010","glossary\u002Feu-directive-2003-10-ec","hRoOXvEkDoKPXQONC3NVWwnFXe-7hcB2e1frGZQrQLA",[221,312,498],{"id":222,"title":182,"aliases":223,"body":227,"category":201,"description":299,"extension":203,"meta":300,"navigation":205,"path":131,"relatedTerms":301,"seo":303,"sources":306,"stem":310,"term":182,"__hash__":311},"glossary\u002Fglossary\u002Fosha-29-cfr-1910-95.md",[224,225,226],"OSHA noise standard","29 CFR 1910.95","OSHA Occupational Noise Exposure",{"type":53,"value":228,"toc":295},[229,234,248,252,259,262,279,281],[56,230,231,233],{},[59,232,182],{}," is the US Occupational Safety and Health Administration's standard for occupational noise exposure in general industry. Two thresholds matter:",[67,235,236,242],{},[70,237,238,241],{},[59,239,240],{},"Action level"," — 85 dBA TWA (time-weighted average over an 8-hour shift) — triggers a hearing-conservation programme",[70,243,244,247],{},[59,245,246],{},"Permissible exposure limit (PEL)"," — 90 dBA TWA — at which engineering controls or hearing protection are mandatory",[89,249,251],{"id":250},"how-it-interacts-with-sonic-horn-installations","How it interacts with sonic-horn installations",[56,253,254,255,258],{},"A ",[97,256,257],{"href":99},"sonic horn"," at the work area can exceed 130 dBA SPL at close range. Operators within ear-shot of firing horns require hearing protection; permanent personnel exposure must be calculated as time-weighted average given the horn duty cycle and operator distance.",[56,260,261],{},"Mitigation options:",[67,263,264,270,273,276],{},[70,265,266,269],{},[97,267,268],{"href":104},"Sound-attenuation enclosures"," at the bell",[70,271,272],{},"Operator-station relocation outside the near-field",[70,274,275],{},"Hearing-protection requirements during horn operation",[70,277,278],{},"Acoustic monitoring during operator-presence audits",[89,280,175],{"id":174},[67,282,283,287,291],{},[70,284,285],{},[97,286,188],{"href":187},[70,288,289],{},[97,290,47],{"href":206},[70,292,293],{},[97,294,193],{"href":104},{"title":195,"searchDepth":196,"depth":196,"links":296},[297,298],{"id":250,"depth":196,"text":251},{"id":174,"depth":196,"text":175},"OSHA 29 CFR 1910.95 is the US Occupational Safety and Health Administration's standard for occupational noise exposure in general industry. Two thresholds matter:",{},[209,302,210],"eu-directive-2003-10-ec",{"title":304,"description":305},"OSHA 29 CFR 1910.95 — US occupational noise exposure standard","OSHA 29 CFR 1910.95 sets US occupational noise exposure limits. The action level is 85 dBA TWA; the permissible exposure limit is 90 dBA TWA. Calculated from time-weighted average exposure.",[307],{"title":308,"url":309},"OSHA — Occupational Noise Exposure","https:\u002F\u002Fwww.osha.gov\u002Flaws-regs\u002Fregulations\u002Fstandardnumber\u002F1910\u002F1910.95","glossary\u002Fosha-29-cfr-1910-95","hQ4_HWPAzxwdcLfEZpimG9KRjWxsXOs-TaAZIXPg29c",{"id":313,"title":314,"aliases":315,"body":318,"category":478,"description":479,"extension":203,"meta":480,"navigation":205,"path":187,"relatedTerms":481,"seo":486,"sources":489,"stem":496,"term":188,"__hash__":497},"glossary\u002Fglossary\u002Fsound-pressure-level.md","Sound pressure level (SPL)",[316,317],"SPL","sound pressure level dB",{"type":53,"value":319,"toc":472},[320,338,342,412,416,429,433,447,449],[56,321,322,324,325,329,330,332,333,337],{},[59,323,314],{}," is the logarithmic measure of sound pressure relative to the 20 µPa human-hearing reference, expressed in ",[97,326,328],{"href":327},"\u002Fglossary\u002Fdecibel","decibels",". It is the primary specification figure for any ",[97,331,257],{"href":99}," or ",[97,334,336],{"href":335},"\u002Fglossary\u002Facoustic-cleaner","acoustic cleaner"," and the metric used to size noise-exposure controls at the work area.",[89,339,341],{"id":340},"industrial-reference-values","Industrial reference values",[112,343,344,354],{},[115,345,346],{},[118,347,348,351],{},[121,349,350],{},"SPL (dB)",[121,352,353],{},"Reference",[134,355,356,364,372,380,388,396,404],{},[118,357,358,361],{},[139,359,360],{},"0",[139,362,363],{},"Threshold of human hearing",[118,365,366,369],{},[139,367,368],{},"60",[139,370,371],{},"Normal conversation",[118,373,374,377],{},[139,375,376],{},"120",[139,378,379],{},"Threshold of pain",[118,381,382,385],{},[139,383,384],{},"140",[139,386,387],{},"Industrial sonic horn (lower-output models)",[118,389,390,393],{},[139,391,392],{},"160",[139,394,395],{},"Typical cement \u002F ESP sonic horn",[118,397,398,401],{},[139,399,400],{},"180",[139,402,403],{},"Upper limit of pneumatic industrial sonic horns",[118,405,406,409],{},[139,407,408],{},"194",[139,410,411],{},"Theoretical maximum for an undistorted sine wave in air",[89,413,415],{"id":414},"spl-and-cleaning-effectiveness","SPL and cleaning effectiveness",[56,417,418,419,423,424,428],{},"Cleaning energy scales with intensity, which doubles for every 3 dB rise. A 150 dB horn delivers roughly twice the energy of a 147 dB horn at the same distance. SPL is not, however, the only selection criterion: ",[97,420,422],{"href":421},"\u002Fglossary\u002Ffrequency","frequency"," determines ",[97,425,427],{"href":426},"\u002Fglossary\u002Fwavelength","wavelength"," and therefore penetration. A 150 dB low-frequency horn typically out-cleans a 160 dB high-frequency horn in a large open vessel.",[89,430,432],{"id":431},"spl-and-exposure","SPL and exposure",[56,434,435,436,440,441,443,444,446],{},"Reported nameplate SPL is measured at 1 m on the bell axis. Real exposure at the work area falls with distance per the ",[97,437,439],{"href":438},"\u002Fglossary\u002Finverse-square-law","inverse-square law"," and through enclosure attenuation. Compliance with ",[97,442,182],{"href":131}," and ",[97,445,47],{"href":206}," is calculated from exposure, not from nameplate SPL.",[89,448,175],{"id":174},[67,450,451,456,461,467],{},[70,452,453],{},[97,454,455],{"href":327},"Decibel",[70,457,458],{},[97,459,460],{"href":421},"Frequency",[70,462,463],{},[97,464,466],{"href":465},"\u002Fglossary\u002Fsound-power-vs-sound-pressure","Sound power vs sound pressure",[70,468,469],{},[97,470,471],{"href":438},"Inverse-square law",{"title":195,"searchDepth":196,"depth":196,"links":473},[474,475,476,477],{"id":340,"depth":196,"text":341},{"id":414,"depth":196,"text":415},{"id":431,"depth":196,"text":432},{"id":174,"depth":196,"text":175},"acoustics-physics","Sound pressure level (SPL) is the logarithmic measure of sound pressure relative to the 20 µPa human-hearing reference, expressed in decibels. It is the primary specification figure for any sonic horn or acoustic cleaner and the metric used to size noise-exposure controls at the work area.",{},[482,422,483,484,485],"decibel","sound-power-vs-sound-pressure","inverse-square-law","sonic-horn",{"title":487,"description":488},"Sound pressure level (SPL) — definition, industrial-cleaning ranges","SPL is the logarithmic measure of sound pressure in decibels relative to a 20 µPa reference. Industrial sonic horns operate at 140–180 dB SPL.",[490,493],{"title":491,"url":492},"Wikipedia — Sound pressure","https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FSound_pressure",{"title":494,"url":495},"Acoustical Society of America — Sound Pressure Level","https:\u002F\u002Fasastandards.org\u002F","glossary\u002Fsound-pressure-level","ayEoQNuJweSv9WGpwDPcx5CMESsbiPd4QPUpIoyQA6M",{"id":499,"title":193,"aliases":500,"body":504,"category":603,"description":604,"extension":203,"meta":605,"navigation":205,"path":104,"relatedTerms":606,"seo":607,"sources":610,"stem":614,"term":193,"__hash__":615},"glossary\u002Fglossary\u002Fsound-attenuation-enclosure-sonic-horn.md",[501,502,503],"sound enclosure","acoustic enclosure","noise-attenuation enclosure",{"type":53,"value":505,"toc":598},[506,524,528,542,546,577,579],[56,507,254,508,511,512,514,515,517,518,443,521,523],{},[59,509,510],{},"sound-attenuation enclosure"," surrounds a ",[97,513,257],{"href":99}," installation to reduce the external ",[97,516,316],{"href":187}," experienced at the operator station, walkways and plant boundary. Typical SPL reduction is 10–25 dB depending on enclosure design — significant enough to bring exposures within ",[97,519,520],{"href":131},"OSHA",[97,522,126],{"href":206}," action limits at most realistic operator distances.",[89,525,527],{"id":526},"when-enclosures-are-specified","When enclosures are specified",[67,529,530,533,536,539],{},[70,531,532],{},"Sonic horns mounted close to operator-access walkways or maintenance positions",[70,534,535],{},"Multi-horn arrays where cumulative SPL exceeds the limit even at modest distance",[70,537,538],{},"Plant boundaries close to residential or commercial property",[70,540,541],{},"Indoor installations where reflection raises ambient SPL",[89,543,545],{"id":544},"trade-offs","Trade-offs",[67,547,548,554,565,571],{},[70,549,550,553],{},[59,551,552],{},"Cost"," — enclosures typically add 10–20% to the installed cost of the horn system",[70,555,556,559,560,564],{},[59,557,558],{},"Maintenance access"," — must be designed to allow routine ",[97,561,563],{"href":562},"\u002Fglossary\u002Fdiaphragm-replacement-sonic-horn","diaphragm replacement"," and inspection",[70,566,567,570],{},[59,568,569],{},"Thermal management"," — for hot-side installations, enclosure ventilation must prevent overheating of accessories",[70,572,573,576],{},[59,574,575],{},"Slight SPL reduction inside the vessel"," — usually marginal, but worth checking in marginal-coverage cases",[89,578,175],{"id":174},[67,580,581,586,590,594],{},[70,582,583],{},[97,584,585],{"href":99},"Sonic horn",[70,587,588],{},[97,589,188],{"href":187},[70,591,592],{},[97,593,182],{"href":131},[70,595,596],{},[97,597,47],{"href":206},{"title":195,"searchDepth":196,"depth":196,"links":599},[600,601,602],{"id":526,"depth":196,"text":527},{"id":544,"depth":196,"text":545},{"id":174,"depth":196,"text":175},"controls-ancillaries","A sound-attenuation enclosure surrounds a sonic horn installation to reduce the external SPL experienced at the operator station, walkways and plant boundary. Typical SPL reduction is 10–25 dB depending on enclosure design — significant enough to bring exposures within OSHA and EU 2003\u002F10\u002FEC action limits at most realistic operator distances.",{},[485,209,208,302],{"title":608,"description":609},"Sound-attenuation enclosure — reduces sonic-horn noise at the work area","A sound-attenuation enclosure surrounds the sonic horn to reduce SPL at the operator station. Typical 10–25 dB reduction; required where horn proximity exceeds OSHA \u002F EU action levels.",[611],{"title":612,"url":613},"Wikipedia — Noise control","https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FNoise_control","glossary\u002Fsound-attenuation-enclosure-sonic-horn","FR-H0qOqUvf8TGgdJbftenNX1Kg25JjWSxU9992_BLY",1782613754568]