Mfutuma a Ɛpae a Ɛhyew ne Class D Metal Powder Ogya¶

Ɛkame ayɛ sɛ nneɛma a ɛyɛ den biara a ɛwɔ abɔde mu anaa dade a ɛtumi hyew oxidized a ebetumi ahyew kɛse, ne nneɛma pii a ɛte sɛ nea entumi nhyew koraa wɔ ade a ɛyɛ den mu, te sɛ aluminium, titanium, magnesium, dade, atoko starch, asikre a wɔayam, awi esiam, nnua a wɔde sawdust, fango, ne plastic resin, bɛpae wɔ tumi a ɛsɛe ade a ɛwɔ ɔtopae a wɔde pɛtro-mframa mu yɛ no mu bere a wɔayam no ma ayɛ fine no nneɛma nketenkete a wɔde hwɛ nneɛma nketenkete na ɛsensɛn hɔ sɛ mfutuma mununkum wɔ mframa mu. Esiane sɛ mununkum a mfutuma nketenkete a ne kɛse yɛ micron 50 wom no ma mframa a ɛwɔ wim no nya soro mpɛn mpempem pii sen nnua anaa dade a ɛyɛ den nti, anyinam ahoɔden ogyaframa biako, conveyor bearing a ɛyɛ hyew dodo, anaa tramp metal friction spark betumi asɔ supersonic deflagration wave a ɛtu mmirika fa adwumayɛbea bi mu wɔ **mita ɔhaha pii wɔ sekan biara mu **, na ɛma nhyɛso a ɛkɔ 7 kosi 10 bar (100 kosi 145 pounds per square inch / psi), bɛboro nhyɛso a ehia na wɔde abubu kɔnkrit a wɔahyɛ no den silo ne adan a wɔde dade ayɛ a wɔde ayɛ adan no mmɔho du.

Nea ɛma mfiridwuma mu mfutuma a ɛpae yɛ nea edi awu soronko ne afã abien a ɛtoatoa so titiriw kosi nea ɛto so abien. Sɛ ogya a ɛyɛ hyew titiriw anaa pop ketewaa bi a ɛwɔ mpɔtam hɔ ba wɔ mfutuma a wɔboaboa ano baghouse, bokiti elevator nan, anaa hama a wɔde yɛ nneɛma mu a, nhyɛso asorɔkye no wosow ɔdan no atifi adan I-beams, ductwork atifi, ne ɔdan no atifi a ɛsensɛn hɔ. Sɛ wɔama kwan ma sawdust, aburow mfutuma, asikre, anaa dade mfutuma a ɛda hɔ 0.8 milimita (inch 1/32) mpo aboaboa ano wɔ saa nnua a ɛwɔ soro no so a, asorɔkye a ɛma mfutuma no wosow ma mfutuma kɔɔ fam kɔ mununkum kɛse a ɛtrɛw dan mu a ɛhyew sekan fã ketewaa bi akyiri yi wɔ mfutuma a ɛpae a ɛyɛ hu secondary mu. wɔ afifide no nyinaa so. Bio nso, sɛ dade a ɛyɛ adwuma a wɔakyekyɛ mu yiye (te sɛ magnesium swarf, aluminium grinding dust, titanium turnings, anaa 3D-printing metal powders) gye ogya a, nsu, foam, anaa ABC dry-chemical extinguisher a wɔahyɛ da ayɛ a wɔde petepete dade a ɛrehyew no so no ma hydrogen-gas ne steam pae ntɛm ara. Nim a wunim sɛnea wobɛtu afi hɔ ntɛm ara bere a nnwinnade ketewaa biara "abɔ" ansa na ɔtopae a ɛto so abien no abɔ, nea enti a ɛnsɛ sɛ wode mframa a wɔahyɛ no den di dwuma da de bɔ nnua a mfutuma ayɛ so ma anaasɛ wode nsu gu dade a ɛrehyew so, ne sɛnea wode anhwea a ɛyɛ dry anaa sodium chloride flux siw Class D dade ogya ano no gye nkwa.

Yɛ eyi mprempren¶

1. Twe ɔdan no nyinaa mu ntɛm ara sɛ wote "pop," thump, anaasɛ flash a ɛyɛ mum wɔ mfutuma a wɔboaboa ano, aburow nan, silo, anaa duct mu a. Saa mfitiaseɛ thump no yɛ primary dust deflagration; wɔ sikɔne kakraa bi mu no, ne wosow no betumi awosow mfutuma a aboaboa ano afi soro nnua so na akanyan ɔsɛe kɛse ɔdan no nyinaa mu ɔtopae a ɛto so abien. Tu mmirika fi ɔkwan a ɛbɛn fam a wɔfa so fi adi no so kɔ beae a ɛbue a mframa a ɛkɔ soro hyiam a anyɛ yiye koraa no mita 100 (anammɔn 330) a ɛda hɔ fi silo ne abɔnten mfutuma a wɔde gu mu.
2. MMFA nsuo, Class A foam, carbon dioxide (\(CO_2\)), anaa standard multipurpose ABC dry-chemical extinguisher npetepete dadeɛ mfuturo anaa turnings (aluminum, magnesium, titanium, zirconium, sodium, anaa lithium) a ɛrehyew akuwakuw so da. Wɔ ɔhyew a ɛboro digrii Celsius 2,000 (digrii Fahrenheit 3,600), hyew dade a ɛyɛ adwuma yi oxygen molecules fi nsu (\(H_2O\)) ne \(CO_2\) mu tẽẽ, na ɛma hydrogen gas a ɛpae fi mu na ɔtow dade a wɔabɔ no akuturuku wɔ sotɔɔ no mu.
3. Sie Class D dade powder ketewaa bi a ɛrefi ase anaasɛ chip ogya denam brɛoo a wode besie wɔ Class D dry-powder aduru a wɔahyira so (sodium chloride, kɔbere powder, anaa graphite), foundry anhwea a ɛyɛ dry, anaa dry cast-iron borings ase. Mma ntow afiri a wɔde dum gya a wɔde nhyɛso ahyɛ mu tẽẽ nkɔ dade powder a ɛrehyew a wɔaboaboa ano mu da dade ayɛ no mfutuma mununkum a ɛpae a ɛwɔ mframa mu; fa scoop a ne nsa tenten anaasɛ Class D applicator wand a ɛnyɛ den pii fa aduru a ɛyɛ dry no gu so brɛoo.
4. MBUe sawdust bin a ɛrehyew, aburow silo, anaa baghouse dust collector nhwehwɛmu hatch no da. Sɛ wobue hatch a, ɛma oxygen foforo kɔ mfutuma a ɛrehyew a oxygen kɔm de no mu na ɛkanyan mfutuma mununkum a ɛsensɛn hɔ tẽẽ wɔ ogyaframa a ɛhyerɛn no so, na ɛma mfutuma a ɛwɔ akyi no pae ntɛm ara wɔ w’anim.
5. Bɔ fam na bɔ wo mframa kwan ho ban sɛ wɔkyere wo wɔ ogya a ɛrehyerɛn anaa mfutuma a ɛredɛw asorɔkye mu a. Sɛ mfutuma mununkum bi sɔ twa wo ho hyia a, to fam ntɛm ara (ɔhyew ne nhyɛso a ɛboro so no kɔ soro kɔ soro kɔ soro), kura wo home mu anaasɛ fa ntama a ɛyɛ nsu mu home na amma mfutuma a ɛyɛ hyew dodo no anhyew wo ahurututu no, na wea fi fam wɔ wusiw no ase bere a 1-kɔ-3-second ogyaframa anim twam.
6. Frɛ wo mpɔtam hɔ nɔma a egye ntɛmpɛ (911 wɔ United States ne Canada, 112 wɔ Europa Aman Nkabom no nyinaa mu, 999 wɔ United Kingdom) ntɛm ara. Bɔ wɔn a wɔde ogya kɔma wɔn a wɔreba no kɔkɔ titiriw sɛ mfutuma a ɛtumi hyew anaa Klas D dade a ɛyɛ adwuma (magnesium, aluminium, anaa titanium mfutuma) rehyew enti odumgyafo mfa ho a nsu a ɛwɔ nhyɛso kɛse mu a wɔde kɔ dade anaa mfutuma kotoku mu; check nɔma ahorow a egye ntɛmpɛ na ɔhyew.

flowchart TD
    Start["Mfutuma a Ɛtumi Ɔhyew anaa Dade Powder Emergency"] --> Incident{"Mfutuma anaa dade bɛn na ɛrekɔ so?"}
    Incident -->|"Muffled Pop, Wosow, anaa Flash wɔ Duct / Baghouse / Silo mu"| PrimaryBlast["MFURU A ƐPAE KƆBƆ KƆBƆ<br/>1. Hit ntɛmpɛ adwumayɛbea gyinabea / evacuation alarm ntɛm ara<br/>2. Tu fi ɔdan no mu wɔ sikɔne kakraa bi mu ANSA na rafter-mfutuma a ɛto so abien bɛpae<br/>3. Twe wo ho fi baghouse akyi mframa a ɛpae ne silo atifi"]
    Incident -->|"Ogya a Ɛrehyew Wɔ Mfutuma Nhomakorabea, Silo, anaa Hoppers Mu"| Smolder["1. To mfutuma a wɔboaboa ano fan ne conveyor dampers no mu ntɛm ara<br/>2. MMA mmue akwan a wɔfa so kɔ hɔ DA anaasɛ mmɔ mfutuma a ɛrehyew (Backdraft explosion risk)<br/>3. Tu fi hɔ na twɛn Ogya Dwumadibea titiriw inert-gas / nsuyiri mmuae"]
    Incident -->|"Dade Mfutuma, Chips, anaa 3D-Printing Powder a Ɛrehyew (Klas D) ."| MetalFire["1. MFA Nsuo, Foam, CO2, anaa standard ABC ogya dum mfiri nni dwuma DA<br/>2. Dum mframa a wɔde fa mframa mu sɛnea ɛbɛyɛ a dade mfutuma a ɛrehyew no renkɔ soro nkɔ mframa mu<br/>3. Fa Class D powder (Met-L-X / Lith-X / Copper) anaa Bone-Dry Sand<br/>4 scoop sie ogya nketewa brɛoo. Sɛ ogya trɛw anaasɛ ɛfa dade mfutuma kɛse ho a: Tu fi hɔ ntɛm ara"]
    PrimaryBlast --> Medical["Fa nsuo a ɛyɛ nwini (simma 20) sa flash burns na hwɛ sɛ woapira wɔ home mu anaa"]
    Smolder --> Medical
    MetalFire --> Medical

Combustible Dust Pentagon ne afiri a ɛto so abien a ɛpae¶

Sɛnea nneɛma a ɛyɛ den a ɛyɛ mpapahwekwa dan nneɛma a ɛpaapae kɛse¶

Nnipa dodow no ara nim Fire Triangle (Fuel, Oxygen, ne Ignition Source) a wɔagye din no. Sɛ ade a ɛyɛ den betumi ayɛ mfutuma a ɛtumi hyew a, ɛsɛ sɛ wɔde honam fam tebea abien foforo ka ho, na ɛyɛ Five-Sided Combustible Dust Explosion Pentagon:

1. Mfutuma a ɛhyew (Fuel wɔ microscopic particle size mu): Ɔman Ogya Ho Banbɔ Fekuw (NFPA) taa kyerɛkyerɛ mu sɛ nneɛma a ɛyɛ den a wɔakyekyɛ mu yiye a ne kɛse yɛ 500 microns (0.5 millimeters) anaa nketewa (a etumi fa U.S. No. 40 standard sieve mu), a nneɛma nketenkete no nnu 75 microns (a ɛyɛ fɛ te sɛ talcum powder anaa esiam) a ɛde asiane a ɛyɛ basabasa sen biara a ɛbɛpae aba.
2. Oxygen (Oxidizer): Ɛwɔ adwumayɛbea mframa a ɛfata mu ɔha biara mu nkyem 20.9.
3. Ignition source (Heat / Spark): Electrostatic discharge wɔ ungrounded plastic vacuum hoses mu, friction sparks fi loose tramp bolt mu grinder, ball bearing a ɛyɛ hyew dodo wɔ conveyor belt so, welding slag a ɛyɛ hyew, anaasɛ ne ho a ɛyɛ hyew spontaneous combustion wɔ damp grain anaa nnua pellets mu.
4. Mframa mu apete (Suspended dust cloud above the Minimum Explosible Concentration / MEC): Esiam anaa sawdust a ɛyɛ tratraa a ɛte fam komm no betumi ahyew nkakrankakra, nanso entumi mpae kosi sɛ honam fam basabasayɛ bi bɛma so akɔ mframa mu a ne dodow a ɛboro bɛyɛ 20 kosi 60 grams wɔ cubic mita biara mu (0.02 kosi 0.06 ounces wɔ cubic foot biara mu). Wɔ saa dodow no mu no, mfutuma mununkum no yɛ kɛse araa ma wontumi nhu kanea a ɛwɔ watt 25 anaa wo yɔnko dwumayɛni bi a ogyina mita 1.5 kosi 2 (anammɔn 5 kosi 6.5) pefee.
5. Confinement (Enclosure): Sɛ mfutuma mununkum a apete no sɔ wɔ anwenne a wɔato mu, ductwork, bokiti elevator nan, anaa dan a afasu anan ne ɔdan atifi wom mu a, mframa a ɛyɛ hyew kɛse a ɛretrɛw ntɛmntɛm no ntumi mfi mu, na ɛma nhyɛso no yɛ kɛse kosi sɛ anwenne anaa ɔdan no bɛpaapae denneennen.

(Hyɛ no nsow a ɛho hia: Sɛ wɔanto afiase mpo a, Nneɛma 1 kosi 4 nkutoo no, mfutuma mununkum a wɔahyew ma ɛyɛ ogya bɔɔl a ɛhyew a ɛyɛ hyew a ɛkenkan digrii Celsius 1,000 kosi 2,000 a ɛma ɔhyew a edi awu a ne kɛse yɛ pɛ na ɛhyew mframa kwan wɔ adwumayɛbea a wɔabue mu.)

Nea enti a "Secondary Explosion" no sɛe adwumayɛbea ahorow nyinaa¶

Nhwehwɛmu amanneɛbɔ ahorow a U.S. Chemical Safety and Hazard Investigation Board (CSB) ne UK Health and Safety Executive (HSE) de mae no kyerɛ sɛ wɔntaa nkum adwumayɛfo wɔ gya a edi kan a wɔhyew wɔ afiri mu no mu. Mmom no, nnipa a wowuwu wɔ Domino Secondary Explosion no mu:

1. Mfe pii a aniwa nhu aboaboa ano wɔ soro: Mfutuma a ɛyɛ fɛ a oguan guan fi saws, sanders, grain conveyors, sugar mills, anaa powder mixers mu na ɛsensɛn soro wɔ ɔhyew mframa a ɛyɛ hyew so, na ɛtra soro komm wɔ overhead horizontal I-beams, cable trays, fluorescent light fixtures, ne acoustic drop-ceiling tiles a ɛwɔ fam no atifi wɔn a wɔprapra nneɛma no nhu da.
2. Mmara a ɛfa krataa a wɔde kyekyere krataa a ne kɛse yɛ milimita 0.8 (nsateakwaa 1/32) ho: Sɛnea NFPA 652 / NFPA 660 kyerɛ no, sɛ mfutuma a ɛyɛ ɔkra a atɔ fam no kata dan bi nan ase ɔha biara mu nkyem 5 pɛ so (a nea ɛwɔ soro a ɛwɔ soro ka ho) kosi sɛ emu dɔ yɛ milimita 0.8 (nsateakwaa 1/32, nsateakwaa 1/32, ne kɛse te sɛ krataa a wɔde kyekyere nneɛma a wɔahyɛ da ayɛ), pɛtro a ɛdɔɔso wɔ hɔ dedaw a sɛ wɔwosow a, mfutuma mununkum a ɛpae bɛhyɛ dan no nyinaa ma fi fam kosi soro.
3. The acoustic shockwave trigger: Ogya titiriw ketewaa bi ba wɔ mfutuma a wɔboaboa ano anaa aburow elevator boot a asiw mu, na ɛte sɛ aprannaa a ɛwɔ akyirikyiri anaasɛ pallet a ahwe ase. Saa nhyɛso asorɔkye no tu fa dade a wɔde fa nsu mu no so na ɛwosow ɔdan no ho.
4. Osu tɔ petrol: Mfutuma a ɛyɛ nwunu a ɛte sɛ powder gram ɔpepem pii tɔ fi soro nnua ne atoro ɔdan atifi ba fam wɔ adwumayɛbea no fam a ne tenten yɛ mita 100 no nyinaa so, na ɛma mfutuma a ɛyɛ kusuu a ɛtrɛw ntɛm ara ba ɔdan no nyinaa mu. Sekan fã akyi no, ogyaframa a ɛredi akyi a efi nsu kwan a apaapae no mu no du mfutuma mununkum a ɛrehwe ase no ho na ɛpae ɔdan no nyinaa wɔ ɔtopae a ɛto so abien mu (ɛtɔ mmere bi a ɔtopae a ɛto so abiɛsa fa akwan ne silo ahorow a ɛka bom so di akyi).

Class D dade ogya a ɛtumi hyew: Aluminium, magnesium, titanium, ne 3D-printing powders¶

Nea enti a nsu ne ogya dum mfiri a wɔde di dwuma daa ma dade ogya pae¶

Wɔ mfiri sotɔɔ ahorow mu, ahunmu adwumayɛ, kar die-casting, foundries, ne additive manufacturing (dade 3D tintim / Direct Metal Laser Sintering), adwumayɛfo mfiri, grind, polish, anaa laser-sinter reactive dade a magnesium, aluminium, titanium, zirconium, hafnium, lithium, sodium, ne potassium ka ho.

Sɛ dade mfutuma a wɔakyekyɛ mu yiye, drill swarf, lathe turnings, anaa wet grinding sludge sɔ a, ɛhyew wɔ ɔhyew a ano yɛ den a ɛwɔ 2,000 kosi 3,300 degrees Celsius (3,600 ne 6,000 degrees Fahrenheit) a ɛyɛ fitaa anaa ultraviolet a ɛyɛ anifurae:

1. Nea enti a Nsu (\(H_2O\)) kanyan hydrogen a ɛpae: Sɛ ɛyɛ digrii Celsius 2,500 a, dade a ɛyɛ adwuma no wɔ nnuru a ɛne oxygen wɔ abusuabɔ a emu yɛ den koraa sen hydrogen. Bere a nsu asuten biako bɔ magnesium, aluminium, anaa titanium powder a ɛrehyew no, dade a wɔabɔ no tetew oxygen atɔm no fi nsu no mu nneɛma nketenkete no mu tẽẽ ma ɛyɛ dade oxide, na ɛma hydrogen mframa (\(H_2\)) a ɛnyɛ hwee pii fi mu sɛnea ɔhyew a ɛyɛ basabasa a efi mu ba no te: $\(\text{Mg} + \text{H}_2\text{O} \rightarrow \text{MgO} + \text{H}_2\uparrow + \text{Ɔhyew}\)$ Saa hydrogen mframa a wɔagyae no fra sotɔɔ mu mframa na ɛpae amonom hɔ ara, bere a nsu a aka no hyerɛn ma ɛyɛ hyew (ɛtrɛw mpɛn 1,700 wɔ ne kɛse mu), na ɛtow dade a wɔanwene a ɛyɛ fitaa a ɛyɛ hyew kodu mita 30 (anammɔn 100) kɔ baabiara.
2. Nea enti a Carbon Dioxide (\(CO_2\)), Halon, ne ABC Dry Chemical afiri a wɔde dum gya di huammɔ na ɛpae:
3. Carbon Dioxide (\(CO_2\)): Magnesium, titanium, ne aluminium a wɔhyew no hyew denam carbon dioxide a ɛho tew so pɛɛ, yi oxygen atɔm no fi \(CO_2\) mframa no mu na ɛma carbon soot tuntum no kɔ akyi bere a ɛma ogya no yɛ ntɛmntɛm.
4. Standard Multipurpose ABC Dry Chemical (Monoammonium Phosphate) ne BC (Sodium Bicarbonate): Sɛ ɛyɛ digrii Celsius 2,500 a, ammonium phosphate porɔw denneennen na ɛne magnesium anaa aluminium a ɛrehyew no yɛ adwuma, bere a nitrogen a ɛwɔ nhyɛso kɛse mu a efi ade a wɔde dum gya mu no pae dade powder a ɛrehyew no kɔ soro mframa, a ɛdan adwumayɛbea ketewa bi a wɔaboaboa ano ogya ma ɛbɛyɛ owuyare Klas D dade mfutuma a ɛpae.
5. Nitrogen (\(N_2\)) gas NNYƐ nea ɛnyɛ adwuma wɔ dade nyinaa mu: Bere a nitrogen gas mie ogya a ɛwɔ abɔde mu no, titanium, magnesium, ne zirconium a wɔhyew no ne nitrogen yɛ adwuma tẽẽ wɔ nnuru mu ma ɛyɛ dade nitrides, na ɛkɔ so hyew wɔ nitrogen wim ɔha biara mu nkyem 100 mpo mu (Argon anaa Helium mframa a ɛho tew nkutoo na ɛyɛ nokwarem no, ɛnyɛ adwuma wɔ titanium a wɔhyew mu).

"Thermite" afiri a ahintaw wɔ sotɔɔ mu afiri a wɔde twitwiw nneɛma ne mfutuma a wɔboaboa ano a wɔadi afra mu¶

Ade biako a ɛtaa de ogya a ɛtɔ wɔ adwumayɛbea dade a ɛyɛ hu ba bere a mfiridwumayɛfo de belt sander, bench grinder, anaa dry dust collector koro no ara yam aluminum ne carbon steel (ferrous metal) nyinaa:

• Sɛ wɔyam carbon dade a, ɛma mfutuma pa a wɔde dade oxide (\(\text{Fe}_2\text{O}_3\), rust) akata so.
• Sɛ wɔyam aluminium a, ɛma wonya aluminum powder (\(\text{Al}\)) a ɛyɛ fɛ.
• Iron oxide powder ne aluminium powder a wɔde afra a ɛbɛn no ne nnuru a wɔde yɛ Thermite pɛpɛɛpɛ. Bere foforo a odwumayɛni bi de ne nsa bɛka dade bi akɔ ntwahonan a wɔde twitwiw nneɛma no so na ɔde ogyaframa a ɛyɛ hyew a ɛyɛ borɔdɔma kɔ fam wɔ mframa a wɔde yi mframa mu no mu kɔ mfutuma a wɔde afrafra aluminum ne nkannare a wɔaboaboa ano no mu no, afrafrade no sɔ thermite a ɛyɛ ne ho oxidizing reaction wɔ 2,500 degrees Celsius (4,500 degrees Fahrenheit) a ɛhyew tẽẽ fa cast-iron floor of afiri no na wontumi dum wɔ nsu ase mpo efisɛ ɛde n’ankasa oxygen fi dade oxide no mu ma.

Anamɔn biara nhyehyɛe a wɔde dum Class D dade ogya ketewaa bi¶

Sɛ ɛyɛ ketewa, a ɛwɔ chips/turnings a wɔaboaboa ano ketewaa bi anaa mfiri tray biako mu nkutoo, na ɛnkɔ soro ankɔ mfutuma mununkum a ɛwɔ mframa mu nkutoo a, bɔ mmɔden sɛ wubedi dade ogya a ɛyɛ adwuma so nkutoo. Sɛ mfutuma a wɔboaboa ano, wet scrubber (a ne nsuo no antumi anyɛ adwuma), anaa bulk drum a dadeɛ powder ayɛ no gya a, tu dan no mu ntɛm ara.

1. Dum mpɔtam hɔ mframa fan ne mfiri coolant pumps ntɛm ara: Sɛ wogyae mframa a ɛsen no a, ɛmma powder a ɛrehyew no ntumi nkɔ nsuo a ɛwɔ soro no mu baabi a ɛbɛtumi apae.
2. Bɔ w'ani ho ban fi ultraviolet (UV) mframa a ano yɛ den ho: Magnesium ne titanium a ɛhyew no ma hann fitaa a ɛyɛ hu ne actinic fitaa a ebetumi ama photokeratitis ("welder's flash") a emu yɛ den aba wɔ sikɔne kakraa bi mu; hwɛ wɔ ɔkwan a ɛnteɛ so anaasɛ hyɛ ahobammɔ ahwehwɛ/anim kyɛm a wɔayɛ no sunsuma; hwɛ aniwa a ɛyɛ ahɔho ade, ani a ɛyɛ mmerɛw, ne welding flash.
3. Paw Class D ade a wɔde dum gya a wɔagye atom NKUTOO a ɛne dade pɔtee no hyia:
4. Sodium Chloride-based Class D Dry Powder (e.g., Met-L-X / Super-D): Ɛwɔ sodium chloride nkyene a wɔayam a wɔayam a wɔde thermoplastic afrafra mu. Ɛfata ma magnesium, sodium, potassium, ne aluminium chip ogya; ɔhyew no ma nkyene no yɛ akutu a mframa ntumi nkɔ mu a mframa pa nni mu. (MFA nni dwuma wɔ lithium ogya so.)
5. Kɔbere Powder Class D Agent (Navy 125S): Wɔayɛ no titiriw ama lithium ne lithium-alloy ogya; kɔbere a wɔde lithium a ayɛ hyew afra mu ma ɛyɛ akutu a ɛnyɛ adwuma a ɛde ɔhyew kɔ.
6. Graphite Powder Class D Agent (G-Plus / Lith-X): Ɛma ɔhyew kɔ na ɛmene lithium, magnesium, titanium, ne zirconium ogya a ɛnyɛ nnuru.
7. Bone-Dry Foundry Sand anaa Dry Cast-Iron Borings (Emergency Shop Improvisation): Sɛ Class D dum afiri a ɛyɛ kɔkɔɔ a wɔatu ho ama no nni baabi a wo nsa bɛka a, wobɛtumi de silica anhwea a ɛyɛ nnompe a ɛyɛ nnompe koraa, pon so nkyene a ɛyɛ dry/rock salt a ɛho tew, anaa dry cast-iron a ɛho tew ahyɛ adwumayɛbea ketewa bi a wɔaboaboa ano a ɛyɛ magnesium anaa aluminium turnings lathe borings a wɔde sie bokiti a wɔatoto mu a nsu ntumi nkɔ mu mu. (Kɔkɔbɔ: Mfa abɔnten anhwea a ɛyɛ nwini anaa abotan a ɛyɛ nsuo a ɛfiri gyaade no nni dwuma da; nsuo a ɛwɔ anhwea a ɛyɛ nwini mu no bɛma nsuo a ɛyɛ nwini/hydrogen apae.)
8. Fa scoop a ne nsa tenten anaasɛ applicator wand a ɛnyɛ den pii fa aduru no gu so brɛoo:
9. Mfa powder ntow tẽẽ nkɔ dade mfutuma a ɛrehyew no mfinimfini da. Sɛ wode Class D dum afiri a ɛyɛ kɔkɔɔ a wɔahyɛ no den redi dwuma a, gyina akyi mita 1.5 kosi 2.5 (anammɔn 5 kosi 8), bue nozzle applicator valve no brɛoo sɛnea ɛbɛyɛ a powder sukyerɛmma a ɛyɛ brɛoo na ɛnyɛ ntɛmntɛm bɛkata ogya no so, na yɛ ade a ɛyɛ pɛ anyɛ yiye koraa no sɛntimita 3 kosi 5 (1.2 kosi 2 inches) kɛse a ɛkata dade a ɛrehyew no so koraa.
10. Sɛ wode bokiti a ɛyɛClass D powder anaa anhwea a ɛyɛ nnompe redi dwuma a, fa sɔw a ɛyɛ tratraa a ne nsa tenten yɛ de powder no to brɛoo twa ho hyia ne nea ɛrehyew no atifi a worenkanyan anaasɛ worentow dade no.
11. Nhaw crusted pile no kosi sɛ ɛbɛyɛ nwini koraa: Wɔ nkyene anaa anhwea a ayɛ mmerɛw no ase no, dade a ayow no kɔ so tra ne auto-ignition temperature so simma 30 kosi 90. Sɛ baabi kɔkɔɔ a ɛyɛ hyew hyew fa abon no mu a, fa Class D powder scoop foforo gu saa beae no so brɛoo. Mfa tow anaasɛ nsɔw aboaboa no mu da kosi sɛ infrared thermometer a ɛnyɛ nea ɛka ho bɛkyerɛ sɛ ayɛ nwini akodu dan mu hyew mu.

Mmoa a edi kan ma mfutuma a ɛpae a ɛpae ne dade a ɛhyew¶

Wɔn a wonyaa wɔn ti didii mu wɔ mfutuma ogya a ɛhyew anaasɛ ɔtopae a ɛto so abien mu no hu amane wɔ ɔhyew, ɔhome, ne barotrauma mu opira ahorow a ɛyɛ den a wɔaka abom:

1. Fa nea wɔayɛ no bɔne no kɔ mframa pa a mframa bɔ mu na dum adwuma ntade a ɛrehyew ("Stop, Drop, and Roll" anaasɛ fa nsu gu mu, GYE SƐ wɔde dade mfutuma a ɛyɛ adwuma akata so):
2. Sɛ odwumayɛni bi ntade rehyew esiane ogya a ɛwɔ mfutuma a ɛnyɛ nkwa mu (nnua, aburow, asikre, esiam, fango, plastic) mu a, fa nsu anaa aguaree a ahobammɔ wom gu mu ntɛm ara.
3. Critical exception for reactive metal dust on clothing: Sɛ wɔde magnesium, aluminium, lithium, anaa sodium powder a ɛnhyew anaasɛ ɛrehyew akata odwumayɛni bi akataso so a, mfa nhyɛ nsuo ketewa bi ase boa wɔn ma wonyi akyi nkataso no ntɛm ara (fa trauma shears di dwuma de twa ntade) bere a wɔde nsu a ɛsen pii rehohoro powder a ɛyɛ dry a ɛho ayɛ hare no ansa na wode nsu pii a ɛreworo so ama honam ani hyew a ɛwɔ ase no ayɛ nwini simma 20; hwɛ severe burns and chemical flushing.
4. Sɛhwɛ sɛ mframa kwan mu ɔhyew a wɔhome no apira ntɛm ara: Sɛ odwumayɛni bi home bere a mfutuma rehyew ogya bɔɔl a, wɔtwe mfutuma nketenkete a ɛrehyew kɔ anom ne ahurututu no mu kɔ akyiri. Hwehwɛ anom nhwi a ɛyɛ biako, nsu a atwa ano anaa tɛkrɛma ho ahyia, kɔbere ɔfe, a ɛyɛ dede, anaasɛ ahurututu a ɛkɔ soro (stridor). Mframa kwan a mfutuma a ɛyɛ hyew dodo ahyew no betumi ahuru ato mu koraa wɔ simma 20 kosi 45 mu; fa ɔyarefo a n’adwene mu da hɔ na ɔhome tra ase gyina hɔ tẽẽ wɔ digrii 45 (a ɛma mframa kwan mu akisikuru no brɛ ase) na yɛ nhyehyɛe ma oduruyɛfo a ɔboa no ntɛm ara ma wɔde endotracheal intubation bɛhyɛ no ntɛm.
5. Fa tap nsuo a ɛyɛ nwini a ɛyɛ nwini ma honam ani hyew a ɛyɛ nwini simma 20, afei siw hypothermia ano: Fa nsuo a ɛyɛ nwini (15 kɔsi 20 degrees Celsius / 59 kɔsi 68 degrees Fahrenheit, nsukyenee da) hohoro nsa, anim, ne abasa a ahyeɛ no simma 20, yi nkaa ne watches ansa na nsateaa no ahonhon, na kyekyere ɔhyew no wɔ plastic a ɛho tew a ɛbata ho (a wɔde ato hɔ tenten, a wɔmfa nkyekyere no denneennen te sɛ tourniquet) anaasɛ ntama a ɛnyɛ nea ɛbata ho a ɛnyɛ den mu bere a wɔde ntama ma ɔyarefo no mu yɛ hyew no; hwɛ ɔhyew.
6. Hwɛ sɛ ɔtopae no apirapira titiriw ne nea ɛto so abiɛsa: Sɛ ɔtopae no bɔɔ afasu anaasɛ ɛtow nea wɔakum no no guu mfiri so a, hwɛ sɛ aso mu ntini apaapae, ahurututu a ɛpae (mogya a ɛyɛ pink a ɛyɛ frothy a ɔfefe, ahome a ɛyɛ tiaa kɛse), shrapnel a ɛhyɛn mu, ne akyi berɛmo anaa ne ti mu apirakuru hwɛ ogyaframa a ɛpae, sparkler a ɛhyew, ne ɔtopae a ɛpaapae.

Facility dust hazard ofiehwɛ ne prevention checklist¶

Mfutuma a ɛto so abien a ɛpae anaasɛ Class D sotɔɔ mu ogya a wobesiw ano no gyina mfiridwuma ne ofiehwɛ ho nteɛso a emu yɛ den so:

• Fa "Paperclip Rule" a ne kɛse yɛ milimita 0.8 (1/32-inch) no nni dwuma wɔ soro: Hwɛ soro I-beams, ductwork, kanea a wɔde hyɛ mu, ne ɔdan atifi a ɛsensɛn hɔ no atifi dapɛn biara. Sɛ mfutuma a atɔ fam no de paint a ɛwɔ ase no kɔla sie anaasɛ ɛboro milimita 0.8 (nsateakwaa 1/32) wɔ dan no mu ɔha biara mu nkyem 5 a, to nneɛma a ɛma ogya hyew no mu na siesie ntɛm ara.
• MMFA mframa a wɔahyɛ no den ("blow-down") anaasɛ dry sweeping nni dwuma mfa nhohoro mfutuma a ɛtumi hyew ho: Sɛ wode 6-bar (90-psi) compressed-air nozzle bɔ sawdust, esiam, anaa dade mfutuma a aboaboa ano fi rafters anaa mfiri so a, ɛma mfutuma mununkum a ɛpae a ɛsensɛn hɔ pɛpɛɛpɛ a ehia na wɔde abɔ ɔdan no. Fa Class II, Division 1 vacuum cleaners a ɛnyɛ nea ɛpae nkutoo di dwuma (dade nkotoku a ahobammɔ wom ankasa, a ɛwɔ fam a ɛyɛ static a ɛwɔ hoses a ɛma nsu fa mu, ɛnyɛ plastic atrae sotɔɔ mu vac da).
• Mfa plastic PVC paipu nni dwuma da mma nnua adwuma anaa mfiridwuma mu mfutuma a wɔboaboa ano: Mframa a wɔde sawdust mmirikatu fa plastic PVC paipu a ɛnyɛ nea ɛde nsu kɔ mu no ma anyinam ahoɔden a ɛyɛ static volt mpempem du du; fa grounded spiral metal ductwork (anaasɛ bond na ground mfutuma a wɔboaboa ano no afã horow nyinaa daa).
• Tetew aluminium/magnesium a wɔyam no mu denneennen fi dade/dade a wɔyam no ho (Siw Thermite): Hyɛ mfutuma a wɔde twitwiw nneɛma a ɛsono emu biara, a wɔakyerɛw so pefee ne mfutuma a ɛyɛ nsu a wɔde boaboa mfutuma ano a wɔde yɛ aluminum, magnesium, anaa titanium nkutoo; nnyam dade a ɛyɛ dade da wɔ afiri a aluminium mfutuma wom so, na tew nsu a ɛyɛ nsu a wɔde popa nsu mu da biara da sɛnea ɛbɛyɛ a hydrogen mframa rentumi nkɔboaboa ano wɔ hood no mu.
• Fa Class D ogyadum afiri kɔkɔɔ ne anhwea bokiti a ɛyɛ dry si mita 10 (anammɔn 33) fi mmeae a wɔyɛ dade adwuma ne 3D-tintim nyinaa: Tete obiara a ɔde di dwuma no sɛ ɔntwe ABC anaa CO2 odumgyafo kɔkɔɔ wɔ dade chip ogya so da.

Frequently asked questions¶

Dɛn nti na asiane wom saa sɛ wode hose a mframa a wɔahyɛ no den bedi dwuma de abɔ sawdust anaa aburow mfutuma afi nnua ne mfiri ahorow so?¶

Mfutuma a ɛte petee wɔ ɔdan a ɛwɔ soro anaa mfiri pon so no ntumi mpae kosi sɛ ɛbɛpete mframa mu sɛ mununkum a ɛsensɛn hɔ. Sɛ odwumayɛni bi de mframa a wɔahyɛ no den a ano yɛ den di dwuma de bɔ sawdust, esiam, asikre, anaa dade mfutuma a aboaboa ano fi nnua a ɛwɔ soro anaasɛ anyinam ahoɔden nkuku mu a, mframa a ɛretu no ma nneɛma nketenkete a ɛyɛ fɛ a ɛyɛ kilogram kɔ ​​soro tẽẽ kɔ mununkum a ɛyɛ den a ɛwɔ mframa mu a ɛboro Minimum Explosible Concentration (MEC) mu. Sɛ saa mununkum a ɛresiane no ne kanea a ɛyɛ hyew biako, anyinam ahoɔden mfiri brush spark, space heater, anaasɛ static discharge a mframa hose no ankasa de ba no di nkitaho a, ɔdan no nyinaa sɔ ntɛm ara wɔ ogya a ɛyɛ hyew anaa mfutuma a ɛpae mu. Bere nyinaa fa mfiridwuma mu vacuum nhyehyɛe a ɛnyɛ nea ɛpae, a wɔde ahyɛ fam anaa akwan a wɔfa so hohoro nsu mu hohoro mfutuma ho wɔ baabi a ɛfata.

Ɛbɛyɛ dɛn na aduan mu nneɛma a wɔtaa de di dwuma te sɛ asikre a wɔayam, atoko, anaa awi esiam atumi apae te sɛ dynamite?¶

Nnuru ahoɔden pii wɔ carbohydrate biara a ɛwɔ nipadua mu (asikre, starch, esiam, aburow, kokoo, nufusu a wɔayam) mu, calories koro no ara pɛpɛɛpɛ a wo nipadua hyew de yɛ pɛtro. Wɔ asikre a ɛyɛ den anaa esiam a wɔaboaboa ano mu no, oxygen kakraa bi pɛ na ebetumi aka emu molecule ahorow no, enti ɛhyew nkakrankakra anaasɛ ɛyɛ hyew. Nanso, sɛ wɔyam asikre anaa starch ma ɛyɛ nneɛma nketenkete a ennu micron 50 na wɔde sɛn mframa mu sɛ mfutuma mununkum a, oxygen molecule ahorow atwa nneɛma nketenkete biara ho ahyia koraa. Sɛ ogyaframa bi sɔ ade ketewaa biako a, ɔhyew a ɛhyerɛn no sɔ nneɛma nketenkete a atwa ho ahyia no nyinaa bere koro mu wɔ nkɔnsɔnkɔnsɔn a ɛnam mita ɔhaha pii so wɔ sekan biara mu, na ɛma mframa a atwa ho ahyia no hyew bɛboro digrii Celsius 1,500 (digrii Fahrenheit 2,700) wɔ milisekɔn mu na ɛma nhyɛso asorɔkye a ɛsɛe ade a ɛkɔ soro kodu 8 bar (115 psi) ba.

Dɛn nti na nsu a wɔde petepete magnesium anaa aluminium ogya a ɛredɛw so no ma ɔtopae kɛse ba?¶

Dade a ɛyɛ adwuma te sɛ magnesium, aluminium, titanium, zirconium, ne lithium hyew wɔ ɔhyew a ano yɛ den a efi digrii Celsius 2,000 kosi 3,300 (digrii Fahrenheit 3,600 kosi 6,000) mu. Wɔ saa ɔhyew no mu no, nsu ($H_2O$) mma dade no nnwo; mmom no, dade a wɔabɔ no de nnuru yi oxygen atɔm no fi nsu no mu nneɛma nketenkete no mu pɛɛ ma ɛyɛ dade oxide, na ɛma hydrogen mframa kronkron a ɛpae ($H_2$) mununkum fi hɔ ntɛm ara bere a ɛma nsu a aka no hyerɛn kɔ nsu a ɛyɛ hyew kɛse mu no. Saa hydrogen mframa no pae ntɛm ara wɔ mframa a atwa ho ahyia no mu, na ɛpae dade kurukuruwa a ayow wɔ dan no mu nyinaa. Bere nyinaa fa Class D dry-powder aduru a wɔatu ho ama (te sɛ sodium chloride nkyene flux, kɔbere powder, anaa graphite) anaa anhwea a ɛyɛ nnompe a ɛyɛ nnompe koraa sie brɛoo bere nyinaa.

Dɛn ne "paperclip mmara" a ɛfa mfutuma a ɛtumi hyew a ɛboaboa ano wɔ adwumayɛbea anaa adwumayɛbea?¶

Sɛnea Ɔman Ogya Ho Banbɔ Fekuw (NFPA 652 ne NFPA 660) kyerɛ no, wubetumi de dade krataa a wɔde kyekyere krataa a wɔahyɛ da ayɛ no kɛse bɛyɛ milimita 0.8 (nsateakwaa 1/32) ayɛ nhwehwɛmu a ɛyɛ ntɛm ahwɛ sɛ mfutuma bɛpae a ɛto so abien anaa. Sɛ mfutuma a ɛyɛ hyew a atɔ fam (te sɛ nnua a wɔde sawdust, aburow mfutuma, esiam, plastic resin, anaa fango mfutuma) aboaboa ano a ne kɛse yɛ milimita 0.8 (nsateakwaa 1/32) anaa nea ɛboro saa wɔ ɔdan bi fam ɔha biara mu nkyem 5 pɛ so (sɛ yɛkan soro dan a ɛwɔ soro a ɛwɔ I-beams, ducts, kanea a wɔde si hɔ, ne nnwinnade a) a, saa dan no mu duru a ɛdɔɔso dedaw pɛtro a wɔde ahyɛ mu ma ama mfutuma a ɛto so abien a ɛpae a ɛyɛ asiane aba sɛ wosow ketewaa bi wosow mfutuma no kɔ mframa mu a.

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Saa akwankyerɛ yi de ahosiesie a egye ntɛmpɛ ne mmoa a edi kan ho nsɛm ma wɔ mfutuma a ɛpae ne Class D dade ogya ho na ɛnhyɛ mfiridwuma mu nhyehyɛe ahobammɔ mfiridwuma anaa odumgyafo ntetee ananmu. Susuw ho sɛ wobɛfa nsaano mmoa a edi kan ne CPR adesua afi Red Cross, St John Ambulance, anaa mpɔtam hɔ ahobammɔ ahyehyɛde bi hɔ.

Akwankyerɛ ahorow a ɛfa ho¶

• Ɔhyew ne ɔhyew a ɛyɛ hyew mmoa a edi kan
• Ɔhyew a emu yɛ den ne nnuru a wɔde hohoro no
• Ogya a ɛpae, sparkler hyew, ne ɔtopae a ɛpaapae
• Mfiri a wɔde yɛ mfuw PTO entanglement ne aburow bin entrapment
• Lithium-ion batere no hyew
• Workplace injuries and industrial accidents

Sources checked¶

• Ɔman Ogya Ho Banbɔ Fekuw (NFPA, United States): Gyinapɛn a Ɛfa Mfutuma a Ɛtumi Ɔhyew Ho Mfitiase Ho (NFPA 652 / Consolidated Standard for Combustible Dusts NFPA 660), Gyinapɛn a Wɔde Siw Ogya ne Mfutuma a Ɛpae wɔ Kuadwuma ne Aduan Ho Nnwumayɛbea Ahorow (NFPA 61), ne Gyinapɛn a Ɛfa Dade a Ɛhyew Ho (NFPA 484)
• U.S. Nnuru Ahobammɔ ne Asiane Nhwehwɛmu Boayikuw (CSB, United States): Mfutuma a Wɔhyew Asiane Ho Adesua Nhwehwɛmu Amanneɛbɔ (Amanneɛbɔ a Ɛto so 2006-H-1) ne Ahemman Asikre / Dade Mfutuma Asɛm Ho Amanneɛbɔ
• Adwumayɛ mu Ahobammɔ ne Akwahosan Dwumadibea (OSHA, United States): Mfutuma a Ɛhyew Ɔman Si so dua (CPL 03-00-008) ne Ahwɛyiye a Wɔyɛ wɔ Ogya a Wɔdum ho wɔ Class D Dade a Ɛtumi Ɔhyew Ogya Ho
• Akwahosan ne Ahobammɔ Dwumadibea (HSE, United Kingdom): Mfutuma a Ɛtumi hyew a Wɔde Di Dwuma Dwoodwoo: Ahwɛyiye a Wɔyɛ wɔ Nneɛma a Ɛpae Ho (HSG103) .
• Nnuruyɛfo Asoɛe (IChemE) ne Verein Deutscher Ingenieure (VDI 2263): Mfutuma a Ɛpae \(K_{st}\) Ogya a Ɛpae Nkyerɛase Nkyekyɛmu ne Ɔpae a Ɛto so Abien a Wɔsiw Ano