Ale dirèk nan kontni an

Lahar vòlkanik (Koulman labou), Kouran dansite piroklastik, ak gwo sann ki tonbe

Pandan ke televizyon montre nan eripsyon vòlkanik souvan konsantre sou kouran lav wouj ki ralanti ke moun ka byen lwen soti, dosye jeyolojik mòtalite yo konpile pa Etazini Jeological Survey (USGS) ak Rezo Entènasyonal Volcanic Health Hazard Network (IVHHN) montre ke plis pase 90 pousan nan lanmò ki gen rapò ak vòlkan yo ki te koze pa twa danje ki pi rapid oswa ki pi gaye: **kouran piroklastik ** Lahar vòlkanik (gwo vitès labou tankou konkrè ak koule debri), ak tephra lou ak ashfall ki tonbe sou do kay bilding nan plizyè dizèn kilomèt anba van epi toufe pasaj lè yo ak vè vòlkanik mikwoskopik.

Priyorite ou siviv imedyat pandan yon kriz vòlkanik eksplozif se pou evakye toujou sou alèt ofisyèl anvan koule piroklastik oswa lahars lansman, monte pèpandikilè ak fon rivyè (dwat miray ranpa a nan tè wo, pa janm aval oswa amont sou fon yon fon) si yon lahar gwonde nan direksyon ou, mete sele andedan kay la. respiratè patikil** ak linèt ki pa ayere pandan sann tonbe, epi kontwole akimilasyon do kay ki plat oswa ki ba pant byen pou w ka evakye anvan 10 santimèt (4 pous) sann vòlkanik mouye tonbe estrikti a anlè.

Fè sa kounye a

  1. Evacuate red-zone slopes immediately when an explosive eruption alert is issued: Never wait to see ash or lava before leaving an official volcanic exclusion zone. Pyroclastic density currents race down volcano flanks at 160 to 700 kilometers per hour (100 to 435 miles per hour) at temperatures of 300 to 800 degrees Celsius (570 to 1,470 degrees Fahrenheit), making outrunning them on foot or in a car impossible once they launch.
  2. Si w nan yon fon rivyè epi w tande yon gwo bri oswa yon sirèn lahar, monte tou dwat sou bò vale a imedyatman: lahars (labou) vòlkanik yo ka monte desann nan vale larivyè yo jiska 50 a 100 kilomèt (30 a 60 mil) lwen vòlkan an nan **30 èdtan a 80 kilomèt pou chak ** menm nan yon jou klè oswa semèn apre yon eripsyon fini lè lapli tonbe sou sann ki lach. Lage sache lou epi kouri oswa kondwi pèpendikilè ak kanal larivyè a moute sou yon ridge, yon ti mòn, oswa yon miray kanyon omwen 20 a 30 mèt (65 a 100 pye) anlè fon fon an. Pa janm travèse yon pon pandan yon lahar ap apwoche.
  3. Pwoteje poumon ou ak je w kont sann vòlkanik abrazif imedyatman: Sann vòlkanik se pa lafimen bwa mou; li se pulverize wòch jagged, kristal silica, ak mikwoskopik shards nan vè vòlkanik kouvwi nan korozif silfirik ak asid idroklorik. Mete yon NIOSH N95, EN 149 FFP2/FFP3, oswa P2 mask respiratè patikil (oswa yon twal koton mouye ak plizyè kouch sou nen ou ak bouch ou an ka ijans), retire Lantiy kontak imedyatman, epi mete **linèt ki byen fèmen.
  4. Rete andedan kay la, fèmen HVAC ak admisyon lè, epi sele bouyon pandan gwo sann tonbe: Fèmen epi fèmen tout fenèt yo, pòt yo, klape chemine yo, ak vantilasyon koule. Etenn chofaj santral fòse-lè, fanatik founo, ak èkondisyone fenèt ki rale lè deyò nan kay la oswa boule motè yo sou glase gravye.
  5. Koute do kay ki ap plenyen epi evakye anvan sann mouye depase 10 santimèt (4 pous): Sann vòlkanik sèk peze 5 a 10 fwa plis pase nèj, epi sann vòlkanik ki tranpe ak lapli vin tounen yon plak solid ki peze 1,500 a 2,000 kilogram pou chak 93 pye kib 125 kilogram pou chak pye kib. Si pwofondè sann sou yon do kay ki plat oswa lajè a apwoche 7.5 a 10 santimèt (3 a 4 pous), oswa si pòt enteryè yo bloke, fenèt yo krake, oswa travès plafon yo krake epi yo debloke, evakye bilding lan imedyatman anvan do kay la tonbe.
  6. Avoid driving during active ashfall unless escaping an immediate lahar or pyroclastic zone: Falling ash creates pitch-black zero visibility at midday, clogs engine air filters in minutes (stalling your car permanently), shorts out electrical alternators, and turns roads into slick, brake-destroying glass paste.
flowchart TD
    Start["Explosive Volcanic Eruption, Lahar Siren, or Heavy Downwind Ashfall Warning"] --> ZoneCheck{"1. Which Volcanic Hazard Zone Are You In Right Now?"}
    ZoneCheck -->|Within 10 to 20 km of Crater / Pyroclastic Zone| EvacImmediate["Evacuate Immediately Away from Volcano: Pyroclastic Flows Travel 160 to 700 km/h at 300 to 800 C"]
    ZoneCheck -->|In a River Valley Draining the Volcano (Up to 80 km Away)| LaharClimb["Lahar Mudflow Danger: At First Siren, Ground Tremor, or Rumble, Climb Perpendicular Up Valley Walls 20 to 30 m High"]
    ZoneCheck -->|Downwind Town or City Receiving Falling Ash (Tephra)| AshShelter["Heavy Ashfall Protocol: Move Indoors, Remove Contact Lenses, Put On N95/FFP2 Mask and Goggles"]
    AshShelter --> SealHouse["2. Close All Windows/Dampers, Turn Off HVAC/AC Air Intakes, Disconnect Roof Rainwater Gutters from Cisterns"]
    SealHouse --> RoofCheck{"3. Is Ash Accumulation Approaching 10 cm (4 in) or Is Rain Mixing With Ash on the Roof?"}
    RoofCheck -->|Yes, or Roof Creaks / Doors Jam| RoofEvac["Imminent Roof Collapse: Put On Hard Hat/Helmet, N95, and Goggles, and Evacuate to a Steep-Pitched or Reinforced Shelter"]
    RoofCheck -->|No: Under 5 cm (2 in) Dry Ash| SafeCleanup["Wait Until Ash Stops Falling, Dampen Ash Lightly with Water Mist Before Sweeping, Never Wash Ash Into Drains"]

Comparing the three deadly volcanic hazards: Pyroclastic flows, lahars, and ashfall

Understanding the physical behavior, speed, temperature, and reach of each volcanic hazard explains why survival tactics differ completely depending on whether you are on the volcano's flank, in a downstream river valley, or in a city 100 kilometers downwind.

Hazard Feature Pyroclastic Density Currents (Flows and Surges) Volcanic Lahars (Debris Flows and Mudflows) Volcanic Tephra and Heavy Ashfall
Physical Composition Ground-hugging avalanche of superheated volcanic gas, ash, pumice, and rock fragments produced by a collapsing eruption column or lava dome. High-density slurry of 60 to 80 percent rock, boulders, sand, and volcanic ash mixed with 20 to 40 percent water, resembling wet ready-mix concrete. Airborne rock fragments (tephra): volcanic bombs/blocks (>64 mm), lapilli / cinders (2 to 64 mm), and volcanic ash (<2 mm pulverized glass and mineral shards).
Forward Speed 160 to 700 km/h (100 to 435 mph): Faster than a hurricane or commercial jet takeoff; impossible to outrun. 30 a 80 km/h (20 a 50 mph) nan kanyon apik, ralanti a 15 a 30 km/h (10 a 20 mph) atravè plenn plat kotyè yo. Pote anba van nan nivo siperyè-a 40 a 120 km/h (25 a 75 mil/h), li tabli soti nan syèl la pandan plizyè èdtan jiska jou.
Tanperati 300 a 800 degre Sèlsiyis (570 a 1,470 degre Fahrenheit): Menm lè a limen estrikti ak lakòz fatal poumon tèmik rale. Varye soti nan frèt / anbyen (lahars ki deklanche lapli) rive nan chodman cho, 40 a 95 degre Sèlsiyis (104 a 203 degre Fahrenheit) lè yo fonn dirèkteman sou glasye somè pa wòch cho. Anjeneral refwadi a tanperati lè anbyen lè sann fin tonbe plis pase 10 a 15 kilomèt de vantilasyon an (lapilli pons fèmen ka rete cho ase pou kòmanse dife sou do kay).
Chemen Jeyografik ak Reach Concentrates in valleys around the volcano out to 10 to 30 kilometers (6 to 19 miles), while dilute upper pyroclastic surges can leap right over ridges and cross open water. Strictly follows stream channels, river valleys, and floodplains draining the volcano out to 50 to 100+ kilometers (30 to 62+ miles) from the summit. Lenn chak sifas (ti mòn, krèt, vale, ak vil yo menm) anba van nan vòlkan an atravè santèn a dè milye de kilomèt kare.
When Danger Strikes During active explosive eruptions or when an unstable viscous lava dome collapses silently without an explosion. During eruptions (melting summit snow/ice or breaching crater lakes) AND for months or years after an eruption ends whenever heavy rain washes loose ash off the slopes. During and for hours to days after an explosive Plinian or sub-Plinian eruption plume rises into the atmosphere.
Primary Survival Action Pre-eruption evacuation out of the hazard zone; if caught in the open with zero escape, seek a subterranean cellar or airtight concrete basement immediately. Vertical evacuation: Climb straight up the side of the river valley to high ground 20 to 30 meters (65 to 100 feet) above the river channel within 10 to 30 minutes of warning. Shelter in place with N95/FFP2 respiratory protection and sealed rooms, while monitoring roof load to evacuate before wet ash causes structural collapse.

Pyroclastic density currents: why exclusion zones are non-negotiable

A pyroclastic density current (PDC) is the most lethal phenomenon in volcanology. It consists of two parts moving together at supersonic or near-supersonic speeds: a dense basal pyroclastic flow of boulders, pumice, and ash that hugs valley floors, and an overriding, turbulent, expanding cloud of superheated gas and fine ash called a pyroclastic surge that ignores topography, climbs uphill over mountain ridges, and can even skim across kilometers of ocean or lake water.

How pyroclastic currents form

  1. Eruption column collapse (Fountain collapse): During an explosive eruption, when the volcano blasts out a mixture of rock and ash too dense for convective hot air to carry up into the stratosphere, the towering vertical column suddenly collapses back down under gravity and cascades down all sides of the mountain simultaneously.
  2. Lava dome collapse (Merapi-type or Peléan flow): When thick, sticky, gas-rich magma oozes out of a summit vent to build a steep, unstable mound (lava dome), the side of the dome can crumble away without any warning explosion, unleashing a silent, incandescent pyroclastic avalanche down the slope.
  3. Lateral blast: A landslide strips away the side of the volcano (as occurred at Mount St. Helens in the United States in 1980), uncorking a sideways-directed supersonic blast.

If caught near a volcano when a pyroclastic flow launches

Paske koule piroklastik touye nan kèk segonn atravè inalasyon tèmik ipè egi (respire nan yon sèl gaz 300-a-600-degre-sèlsiy ak sann dife trachea a ak larenks fèmen) ak chòk eksplozyon:

  • Si w nan yon machin sou yon wout ki louvri ak yon nwaj vizib nwa, k ap bouyi ki anbrase tè a k ap desann mòn nan: Kondwi a yon vitès maksimòm san danje lwen vòlkan an epi pèpandikilè ak nenpòt canyon k ap dirije nwaj la. Woule tout fenèt yo byen sere, chanje vantilasyon machin nan Recirculation OFF / konplètman fèmen, epi klakson kontinyèlman pou avèti lòt moun.
  • Si chape enposib epi enpak se kèk segonn lwen (Dènye Rekou Pwotokòl Ditching): Antre anndan estrikti beton ki pi solid ki disponib soutèren an (yon gwo kav anba tè, yon bunker konkrè, oswa yon chanm masonry enteryè ki pa gen fenèt sou bò bilding lan ki fè fas ote vòlkan an). Fèmen tout pòt ak fenèt yo, mouye yon sèvyèt epè oswa yon chemiz imedyatman, sere li byen sou nen ou ak bouch ou, rale rad sou tout po vid, epi pliye nan yon boul ki sere sou planche a fas anba pou pwoteje pasaj ou a pandan 2 a 5 minit nan nwaj sann cho a.

Lahar vòlkanik: siviv gwo vitès labou konkrè nan fon rivyè yo

Mo Endonezyen lahar la dekri yon melanj debri wòch vòlkanik ak dlo ki soti nan pant yon vòlkan k ap koule byen vit, ak gravite. Moun ki pa janm wè yon lahar souvan imajine yon inondasyon dlo labou mawon. An reyalite, yon lahar gen konsistans, pwa, ak pouvwa fizik beton mouye k ap koule nan vitès otowout.

Paske yon lahar gen jiska 80 pousan wòch solid ak sab pa pwa, dansite li se de fwa dlo. Ekstrèm dansite sa a kreye fòs k ap flote tèlman pwisan ke yon lahar pran san efò epi flote boul granit ki gen plizyè tòn, kamyon deboulaj, lokomotiv ray tren, ak tout pon otowout asye, lè l sèvi avèk yo tankou baton jeyan nan devan koule a pou koupe tout kay, pye bwa, ak poto sèvis piblik nan fon an. Pi mal toujou, moman sa a yon lahar ralanti epi gaye nan yon vil plat nan baz vale a, dlo a vide soti nan lisier a ak labou a dewatering ak solidifye tankou siman vide nan kèk minit, pyèj nenpòt moun ki kenbe nan ren-pwofondè tèlman sere ke yo pa ka rale gratis san yo pa gwo machin fouye.

Twa fason lahar yo kòmanse (Sa enkli ane apre vòlkan an ale trankil)

  1. Nèj ak glasye fonn pandan yon eripsyon (Primary Lahar): Lè piroklastik koule cho oswa lav eklate sou yon vòlkan ki kouvri ak nèj oswa glasye (tankou Mòn Rainier, Mòn Hood, oswa Mòn Baker Ozetazini; Nevado del Ruiz nan Kolonbi; Cotopaxi nan Ekwatè; oswa Mòn Ruapeicehu k ap fonn enstantane, chak milyon mèt kib nan Nouvèl Zeland). glacial river valley radiant soti nan pik la.
  2. Volaj lak kratè: Yon eksplozyon fann rebò nan yon lak kratè asid somè, jete yon lak antye desann Canyon an.
  3. Post-eripsyon lapli deklanche lahars (Lahars Segondè): Pou mwa a plizyè ane apre yon gwo eripsyon sann, pant anwo vòlkan yo antere anba mèt sann ki lach, idrofob ki touye tout vejetasyon. Chak fwa yon gwo lapli nòmal oswa yon tifon twopikal frape mòn lan, dlo lapli pa ka tranpe nan sann kwout la; olye de sa, li dra sou pant yo, melanje ak tephra ki lach yo, epi lanse vyolan lapli deklanche larivyè yo nan jou lè vòlkan an tèt li konplètman trankil.

Règ imedyat jaden pou siviv yon lahar

  • Rekonèt siy avètisman akoustik ak vizyèl yo:
  • Sirèn lahar ofisyèl Acoustic Flow Monitor (AFM) lahar (ki fè sonnen yon ton kontinyèl oswa yon alèt vwa atravè fon ki gen gwo risk tankou Puyallup Valley anba Mount Rainier) oswa alèt mobil emisyon ijans.
  • Yon gwo twou san fon, kontinyèl, tren machandiz oswa jè-motè gronde tè ak Vibration ki soti nan amont ki ap grandi pi fò chak segonn (kontrèman ak yon tranbleman tè, ki pik ak fennen nan yon minit, yon gwonde lahar bati piti piti kòm devan wòch la apwoche).
  • Nivo larivyè a toudenkou tonbe oswa seche (ki te koze pa yon glisman tè amont ki tap baraj tanporèman ravin lan) OSWA rivyè a toudenkou vire epè, vapè, labou gri-mawon ak pye bwa k ap flote ak yon sant souf pike.
  • Grenpe LEVE, pa janm eseye depase yon lahar nan fon an:
  • Si w ap mache oswa nan yon liy trafik anboute sou yon fon, vire 90 degre lwen rivyè a epi ale tou dwat moute miray vale ki pi pre a, ti mòn, blòf, oswa ti mòn ki deziyen pou evakyasyon an.
  • Jwenn jis 20 a 30 mèt (65 a 100 pye) nan elevasyon vètikal anlè kanal larivyè Lefrat la mete ou konplètman pi wo a rive nan prèske tout lahars.
  • Pa janm travèse yon pon lè yon lahar ap vini oswa vizib anlè: Lahar yo regilyèman dechire pon yo nan pil beton yo oswa pilye gwo blokaj sou tab pon yo, yo bale tout pon an ak chak machin ki sou li ale nan kèk segonn.
  • Pa janm mache sou yon kwout lahar ki fèk depoze: Menm apre yon lahar sispann deplase, yon kwout gri ki sanble sèk fòme sou tèt nan kèk èdtan pandan enteryè a anba rete san fon, pafwa **sab bouyi-cho ** pou jou oswa semèn. Ap tann jiskaske enjenyè sivil teste kapasite pote a anpeche l ap desann fatal ak boule boule.

Gwo sann vòlkanik (Tephra): efondreman do kay fizik ak siviv estriktirèl

Kontrèman ak sann bwa ki soti nan yon boukan dife oswa dife sovaj (ki se mou, plim kabòn òganik ki fonn nan dlo ak soufle ale nan yon briz), sann vòlkanik konsiste de kristal wòch dente, pulverize ak ti mikwoskopik byen file nan vè silica (\(SiO_2\)) gaz magma ekspansyon apa.

Poukisa sann vòlkanik tonbe twati yo byen lwen pi vit pase nèj

Kòd konstriksyon nan klima frèt yo konsevwa twati rezidansyèl yo pou sipòte nèj, ki se sitou lè bloke epi li peze sèlman 100 a 200 kilogram pou chak mèt kib (6 a 12.5 liv pou chak pye kib). Sann vòlkanik se wòch solid pulverize:

Materyèl sou do kay Tipik nan dansite esansyèl (Pwa pou chak mèt kib) Chaj te ajoute sou do kay pa jis 10 cm (4 pous) nan pwofondè Enpak estriktirèl sou bilding tipik
Nèj fre sèk 100 kg/m³ (6.2 lb/ft³) 10 kg/m² (2 lb/py²), Apeprè 1,500 kg (1.6 tòn) sou yon do kay 150 m² (1,600 sq ft). Fasil sipòte pa prèske tout twati estanda.
Sann vòlkanik sèk 700 a 1,200 kg/m³ (44 a 75 lb/ft³) 70 a 120 kg/m² (14 a 25 lb/py²), 10,500 a 18,000 kg (11,5 a 20 tòn) sou yon do kay 150 m². Depase limit efondreman twati tòl yo, abri machin yo, galri, ansyen twati an bwa, ak gwo depo oswa jimnaz.
Sann vòlkanik mouye/tranpe nan lapli 1,500 a 2,000 kg/m³ (93 a 125 lb/ft³) 150 a 200 kg/m² (31 a 41 lb/py²), 22,500 a 30,000 kg (25 a 33 tòn) sou yon do kay 150 m². Papòt efondreman estriktirèl katastwofik pou pifò twati an bwa rezidansyèl yo ki plat oswa ki ba yo, bastengal, ak goutyè lapli.

Gade pou lapli melanje ak sann sou do kay ou

Sann vòlkanik sèk pore aji tankou yon eponj jeyan sou do kay ou a: lè lapli kòmanse tonbe pandan oswa apre yon sann tonbe, sann nan absòbe epi kenbe chak gout dlo lapli olye pou yo kite l kouri nan goutyè yo. Yon kouch sann 10 santimèt (4 pous) ka double nan pwa nan 30 minit apre lapli tonbe, epi sann mouye pake nan fon do kay la ak bouche goutyè lapli jiskaske goutyè yo dechire tou dwat sou twotwa yo ak baton twati yo kase san avètisman.

Siy avètisman efondreman do kay ki kritik ak règ sann nan netwaye sann

  1. Siveye pwofondè sann ak siy estrès estriktirèl andedan kay la:
  2. Mezire akimilasyon sann sou yon sifas ki plat ak van an deyò yon fenèt. Yon fwa sann yo rive nan 5 a 7.5 santimèt (2 a 3 pous) sou yon do kay ki plat oswa ki ba (oswa si lapli kòmanse tonbe sou sann ki egziste deja), prepare w pou evakye oswa netwaye do kay la sèlman si an sekirite.
  3. Siy evakyasyon imedyat: Si w tande son eklate byen fò, krake, oswa jemi soti nan grenye an oswa nan plafon an, gade lacho oswa klwazon sèch k ap dekale nan jwenti plafon an, remake panno plafon ki febli, oswa jwenn ke **pòt chanm enteryè oswa klozèt toudenkou bloke epi yo pa pral louvri oswa fèmen ** (ki vle di chay ki anba chay miray la). pa monte sou do kay la, mete chapo/kas, mask N95, ak linèt, epi evakye tout moun ki soti nan kay la imedyatman nan yon bilding ki gen yon ankadreman an apik, yon etaj anba beton ranfòse, oswa yon machin ki estasyone nan ouvè lwen pye bwa ak liy kouran elektrik.
  4. Mouri tonbe sou do kay pandan netwayaj: Etid medikal apre eripsyon an (tankou apre eripsyon Mòn Pinatubo 1991 ak Kelud 2014) montre ke plis moun mouri oswa soufri paralize ka zo kolòn vètebral nan glise sou twati sann-slick pandan netwayaj pase nan do kay ki tonbe sou yo andedan kay la. Sann vòlkanik sou do kay metal, mozayik oswa bardo aji tankou dè milyon de woulo bi mikwoskopik, epi li tounen yon grès lis lè mouye.
  5. Si ou dwe netwaye yon do kay ki ba, ki solid pou sove li:
  6. Pa janm ale sou yon do kay pandan w ap tonbe nan sann aktif (vizibilite se zewo, zèklè frape regilyèman andedan sann vòlkanik, ak wòch/lapilli tonbe lakòz zo kase zo bwa tèt) epi pa janm ale sou yon do kay ki deja krake oswa afesman.
  7. Sèvi ak yon rato do-kay ki gen manch long oswa pouse bale pandan w kanpe an sekirite atè oswa yon nechèl estabilize pou retire sann nan fay ki pi ba yo anvan.
  8. Si ou pa ka evite monte sou yon do kay ki ba pant, mete yon balay sekirite ki ankre ak yon kòd k ap grenpe sou yon pye bwa ki solid oswa yon machin ki sou bò opoze kay la, mete yon respiratè N95/FFP2 ak linèt ki sele, epi retire sann sann sistematikman soti nan twòp ki twò chaje yo pou w pa fè menm desann nan twati yo.
  9. Dekonekte goutyè yo nan sitèn dlo lapli ak drenaj franse yo imedyatman: Mete yon ranyon nan tèt goutyè yo oswa wè/dekonekte anba tiyo desandan an anvan yo bale sann sou do kay la; si sann vòlkanik la lave nan tiyo dlo lapli anba tè oswa nan chan drenaj septik, li tabli tankou beton epi pèmanan kraze tout sistèm plonbri a.

Pwoteje poumon, je, ak dlo pou bwè kont sann vòlkanik ak gaz asid

Patikil sann vòlkanik ki fèk tonbe yo souvan pi piti pase 10 mikwomèt (\(PM_{10}\)) ak 2.5 mikwomèt (\(PM_{2.5}\)), sa ki pèmèt yo antre byen fon nan bronchioles tèminal yo ak alveoli nan poumon yo, pandan y ap sifas fre glase yo pote nan (\(**SO4_) asid kondanse. asid idroklorik (\)HCl\(), ak asid idroklorik (\)HF$)**.

1. Pwoteksyon respiratwa (Opresyon, COPD, ak silica cristalline)

  • **Toujou mete yon respiratè pou patikil yo deyò oswa lè w ap bale sann: ** Mask chirijikal estanda pou zòrèy-bouk yo kite twou vid ki laj nan machwè yo ki kite bon vè vòlkanik antre nan pasaj ou yo. Sèvi ak yon NIOSH-apwouve N95, N99, oswa P100 mask (Etazini), yon EN 149 FFP2 oswa FFP3 mask (Ewòp/UK), oswa yon P2 mask (Ostrali/Nouvèl Zeland), zongle pon nen an metal byen sere epi sèvi ak tou de espageti tèt.
  • Mas enpwovize ijans si pa gen N95 ki disponib: Pliye yon mayo koton epè, bandana, oswa sèvyèt plat nan 4 a 8 kouch, mouye li alalejè ak dlo pwòp (pa tranpe mouye, ki bloke respire, jis ase mouye pou patikil sann byen kole nan fib mouye yo ak gaz dioksid souf ak dlo netralize), byen byen sou nen ou ak bouch ou.
  • Opresyon ak bwonchit ki gen gwo risk: Menm moun ki gen timoun piti opresyon ki pa gen bezwen yon inaler nan ane souvan soufri bronchospasm egi grav nan kèk minit nan respire sann vòlkanik oswa diyoksid souf (\(SO_2\)) gaz. Kenbe inalateur sekou (albuterol/salbutamol) nan pòch ou tout tan epi rete entèdi andedan yon chanm ki fèmen jiskaske sann yo poze.

2. Pwoteksyon zye: poukisa lantiy kontak lakòz abrasion grav nan korn

Pa janm mete lantiy kontak pandan oswa pandan plizyè jou apre sann vòlkanik tonbe. Ti mikwoskopik vè vòlkanik glise anba lantiy kontak mou oswa rijid; chak fwa ou bat, lantiy kontak moulen ti moso vè sa yo atravè korn lan tankou papye sab, sa ki lakòz gwo twou san fon, douloure abrasion nan korn ak asid chimik boule.

  • ** Chanje nan linèt epi mete linèt ki pa ayere deyò: ** linèt ski, linèt naje, oswa linèt sekirite endistriyèl sele kontinye soufle sann soti nan je yo.
  • Si sann vòlkanik antre nan je ou: PA fwote je ou. Klike byen vit pandan w apiye sou yon bòl oswa yon koule, rale po je anwo a dousman sou sil ki pi ba yo, epi lave je ki louvri kontinyèlman pou 10 a 15 minit ak yon ti kouran dou nan boutèy saline esteril ki soti nan kwen dlo saline ki pa vide nan kwen dlo a. deyò.

3. Pwoteje dlo pou bwè, bèt, ak griy elektrik

  • Dlo pou bwè ak asid fluororik (\(HF\)) toksisite: Dekonekte goutyè dlo pou dlo lapli nan tank dlo lapli imedyatman lè yon eripsyon kòmanse. Pandan ke sann modere nan rezèvwa minisipal yo sitou lakòz twoub (boubidite) ak gou yon ti kras asid ke plant tretman dlo ka filtre, sann ki soti nan sèten vòlkan ki gen fliyò (tankou nan Islann, Nouvèl Zeland oswa Amerik di Sid) lesivaj toksik ** fliyò ** nan depresyon dlo louvri ak flak dlo, ki ka rapidman pwazon bèt ** nan èdtan ** ak pwazon. Kenbe tout bèt kay ak bèt andedan kay la sou manje ki estoke kouvri ak dlo pwòp tiyo/nan boutèy.
  • **Sann mouye "flashover" blakawout sou griy elektrik: ** Sèk vòlkanik sann se yon izolan elektrik, men moman sa a limyè lapli, vapè dlo, oswa lawouze maten mouye sann nan kouch segondè-vòltaj izolan seramik sou poto sèvis piblik ak transfòmatè, sèl asid ki fonn yo tounen sann mouye nan yon kondiktè elektrik pwisan. Arcs elektrisite wo-vòltaj atravè sann mouye a (izolasyon flashover), soufle transfòmatè ak plonje tout vil yo nan pwolonje. pann kouran jis lè ponp dlo yo bezwen plis. Ranpli basen, po, ak krich dlo ak dlo tiyo pwòp osito w tande yon eripsyon te fèt, anvan nwaj sann nan rive nan vil ou a epi frape rezo elektrik la.

Netwayaj sann ki an sekirite apre eripsyon ak règleman pwoteksyon machin yo

Yon fwa ke sann sispann, netwayaj mande pou pasyans ak sipresyon pousyè tè strik pou ou pa aerosolize ti fragments vè yo tounen nan poumon ou:

  • Bwouye sann yon ti kras ak dlo anvan ou baleye: Pa janm sèk-balye oswa itilize yon soufle fèy sou sann vòlkanik; soufle fèy kreye nwaj silica ki avegle, ki domaje poumon. Sèvi ak yon bouch kawoutchou jaden oswa yon boutèy espre pou yon ti kras mouye sifas sann lan (pa inonde li nan labou), answit pèl li nan sache plastik lou (ranpli chak sak sèlman mwatye plen, kòm yon sak fatra plen sann vòlkanik peze 40 a 60 kilogram / 90 a 130 liv epi li pral dechire oswa nan do w).
  • Pa janm lave sann vòlkanik nan lavabo kay la, twalèt, oswa drenaj tanpèt lari yo: Sann yo rete nan pyèj tiyo ak kanalizasyon egou minisipal epi li vin di nan beton.
  • Netwaye aparèy nan kay la ak yon filtè HEPA vakyòm oswa lè konprese, pa janm siye vè sèk ak yon moso twal: Siye sann sèk sou vit machin, linèt, panno solè, oswa lantiy kamera ak yon ranyon oswa essuie-glaz sèk moulen reyur pèmanan nan glas la. Rense san gad dèyè avèk yon kawotchou an premye, oswa efase dousman ak eponj mouye.
  • **Si ou te oblije kondwi nan sann: ** Ranplase filtè lè motè a ak filtè lè kabin imedyatman, chanje lwil motè a ak filtè lwil oliv, epi fè yon mekanisyen presyon-lave kousinen fren yo, rotor yo, ak lojman altènatè anvan kondwi nòmal.

Kesyon yo poze souvan

What is a volcanic lahar, and how do you survive one if you are in a river valley?

A lahar is a high-speed volcanic mudflow composed of up to 80 percent rock, boulders, and ash mixed with water from melted summit snow/glaciers or heavy rain, giving it the density and destructive power of wet concrete moving at 30 to 80 kilometers per hour (20 to 50 miles per hour). If you hear a lahar siren or a deep freight-train rumble in a river valley draining a volcano, never try to outrun it downstream or cross a bridge; immediately run or drive perpendicular to the river straight up the nearest valley wall or hill to at least 20 to 30 meters (65 to 100 feet) above the valley floor.

How much volcanic ash on a roof can cause the roof to collapse?

Because volcanic ash is pulverized solid rock and glass rather than fluffy snow, it weighs 5 to 10 times more than snow when dry and up to 1,500 to 2,000 kilograms per cubic meter (93 to 125 pounds per cubic foot) when wet. Just 10 centimeters (4 inches) of rain-soaked volcanic ash adds 25 to 33 tons of weight to an average house roof, which is enough to collapse flat roofs, wide-span buildings, carports, and standard timber trusses. Evacuate immediately if ash approaches 10 centimeters or if you hear ceiling beams creaking or doors jamming.

Why must you never wear contact lenses or use windshield wipers without water during volcanic ashfall?

Volcanic ash consists of microscopic, razor-sharp shards of silica glass and hard mineral crystals. If ash slips under a contact lens, blinking grinds those glass shards directly into your cornea, causing severe corneal abrasions. Similarly, running windshield wipers over dry ash on a car windshield grinds the glass into permanent, opaque scratches; always wear eyeglasses and sealed goggles, and flush surfaces with copious water before wiping.

Can a dangerous volcanic mudflow (lahar) happen weeks or months after the eruption is over?

Yes, secondary (rain-triggered) lahars frequently occur months or even years after an explosive eruption ends. Because thick layers of loose volcanic ash kill vegetation and form a water-repellent crust on the mountain slopes, any heavy rainstorm or tropical cyclone can rapidly wash millions of tons of ash into river canyons, triggering deadly concrete-like mudflows on days when the volcano itself is completely dormant.

Why should you never wash volcanic ash down the sink or into street storm drains during cleanup?

When volcanic ash mixes with water and settles inside slow-moving plumbing P-traps, septic tanks, or municipal stormwater pipes, the dense rock and silica particles pack together and harden like poured cement, permanently blocking the entire drainage system. Always dampen ash lightly, shovel it into heavy-duty plastic bags filled only halfway (due to extreme weight), and dispose of it at designated municipal collection points.

Sous yo tcheke

  • Pwogram Danje Volkan nan United States Geological Survey (USGS) : Viv ak Risk Volkanik: Lahars, Koule Piroklastik, ak Chajman Twati ak Netwayaj Sann Volkanik (Tephra).
  • International Volcanic Health Hazard Network (IVHHN), Òganizasyon Mondyal Lasante (WHO), ak Cities and Volcanoes Commission: The Health Hazards of Volcanic Ash: A Guide for the Public ak Gid sou preparasyon anvan, pandan, ak apre yon sann tonbe.
  • Ajans Federal pou Jesyon Ijans (FEMA) ak Ready.gov (Etazini): Preparasyon pou Volkan, Evakyasyon Vètikal pou Lahars, ak Sekirite Chaj Nèj/Sann Estriktirèl.
  • GNS Syans (Te Pū Ao) ak Ajans Nasyonal pou Jesyon Ijans (NEMA, Nouvèl Zeland): Konsekans Volcanic Ashfall sou Enfrastrikti Kritik, Papòt Efondreman Do-kay, ak Sekirite Dlo Agrikòl.
  • Federasyon Entènasyonal Sosyete Lakwa Wouj ak Kwasan Wouj (IFRC, Entènasyonal): * Pwotokòl Repons pou Katastwòf pou Eripsyon Vòlkanik Eksplozif ak Evakyasyon Lahar*.

Gid ki gen rapò