DIP Episode 655 - OMBRS 2-The OSHA Asbestos Standard

Welcome everybody my name is divine this is episode 655 of the Divine Intervention Podcasts. So these podcasts I'm gonna continue the occupational medicine board review series. So the first one that I made a few days back focused on the OSHA lead standard. Now this one is gonna focus on the OSHA as bestos standard okay on the OSHA as bestos standard.

This one should hopefully be a little less complicated than the let's standard but we'll see right and I'm gonna make lots of integrations as we go along just to really help you understand things and you know be prepared from a board's perspective right and again the OSHA as bestos standard it's heavily tested on the occupational medicine boards right if you've been in residency for more than a few months I'm almost certain you've probably heard about as bestos in some way shape or form right so what do the boards actually test right what do they actually test they love to test their regulatory framework you know exposure limits the work classifications medical surveillance requirements right and how often do you need chest X-rays right depending on your age or how long you've been exposed to as bestos they really love to test this on on the exams right so I think I want to maybe start of the spot guys by you know starting off with something that honestly trips up a lot of test stickers right the thing is there's just not one OSHA as bestos standard there's actually two right so we have a 29 cotofedra regulations 19 10.1 0 0 1 right that covers general industry and then we have 29 cotofedra regulations 19 26.11 0 0 1 that covers construction right the thing is did largely share the same core framework but the thing is the construction standard is more far more heavily tested right because think about it that's with the overwhelming majority of as bestos exposure happens in construction right in a renovation demolition of older buildings right so when you see a board vignette about as bestos it almost always involves a construction worker or person that you know works on a shipyard right or someone doing some kind of renovation right so again don't forget two standards exist construction that's 19 26.11 0 1 that's more board tested in general industry so again we got t

o know the numbers as I discussed for lead let's talk about the numbers for as bestos right so let's get the numbers into your head all right let's get the numbers into your head right so what's the P.E.L.

for as bestos right the permissible exposure limit it's 0.1 fibers per cubic centimeter as an eight hour time-witted average literally write that down right now 0.1 cubic centimeter fibers per cubic centimeter as an eight hour time-witted average the short term exposure limit the style is 1.0 fibers per cubic centimeter over any 30-minute period it's not at our time-witted average over any 30-minute period right and here's where test stickers begin to get confused with these numbers right the thing is the action level for as bestos is also 0.1 fibers per cubic centimeter right so literally the P.E.L. and the action level are numerically the same this is something that is very unusual many times the action level is about half the P.E.L. for most OSHA standards but that's not the case here right here the P.E.L. and the action level are numerically the same so what's the difference remember the action level is basically the threshold that triggers two specific things literally triggers two specific things right periodic air monitoring and aromainting medical surveillance right periodic air monitoring and Romani medical surveillance right the P.E.L. is the threshold that you you know is the threshold you cannot exceed right if you exceed the P.E.L.

then it requires you to have engineering controls right so being out of above the action level for 30 or more days per year requires you that hey you're going to enroll that worker in the in the surveillance program right in the surveillance program so again just to summarize the P.E.L. is 0.1 fibers per cubic centimeter as an either our time-witted average the style the short term exposure limit is one fiber per cubic centimeter over any 30-minute period the action level is 0.1 fibers per cubic centimeter it's the same as the P.E.L right but again it kind of triggers different obligations in a sense right so like for example the P.E.L. again 0.1 fibers per cubic centimeter it our time-witted average it triggers engineering controls it engineering controls are required once you go up all the P.E.L right the STEL right one fiber per cubic centimeter right is over any 30-minute time frame this cannot be exceeded in any ten limit any 30-minute window right and then the action level again is also 0.1 fibers per CC right per cubic centimeter right it our over an our time-witted average right it triggers monitoring and medical surveillance right you need to enroll those workers in monitoring and medical surveillance right so again please don't forget the P.E.L. I've said this like three times now the P.E.L. and the action level they're the same number right the love the boards they really love to test that you know that hey if you go above the P.E.L.

it triggers engineering controls are required if you go above the action level it triggers monitoring and medical surveillance right but one number is not lower than the other all right so now let's talk about the work classifications and construction they love to test this many resources don't interest is but it's actually very high yield to know for the boards right this is a section that shows up quite frequently on the in board vignettes right so you really want to pay close attention right so the thing is the construction standard actually does use a classification system for as best as work right uses class one through class four right what's this classification for well the thing is it basically goes from highest risk to lowest risk right so your job on the board is to hear a job description in a vignette and immediately know hey this is the class this falls into right so what's class one well class one is going to be the highest risk category right basically it involves you know removal of you know thermal system insulation you know we're gonna call this TSI I don't keep saying thermal system insulation throughout the spot gas right so TSI right and you know surface in as best as continued material I'm gonna call that ACM so TSI means thermal system insulation ACM just means as best as continued material right so basically if you are a person that removes TSI's and surface ACM's right then you're gonna be in class one right so TSI's like the pipe insulation the boiler wrap the duct insulation you know this was pretty common in buildings you know you know built before 1980 we do different things differently now now surface in ACM's right this includes like again basically like as best as on surfaces right so like spray-done fire profane you know textured ceiling materials right class one requires the most controls right whenever you're doing a class one job rig

ht a competent person has to be on site that's like extremely important competent person has to be on site you need to have full containment you need negative pressure and closures and you often need like a certified industrial hygienist you're doing class one work you better have good people around you right now class two is basically removal of other ACM that is in TSI or surface in material so if you're removing as best as continued material that is not TSI or surface in material right so think of things like you know like floor tiles roofing felt you know sheet gaskets you know siding right it still significant risk still requires controls but not a stringent class one and then class three is repair and maintenance work repair and maintenance work where you may encounter as best of continuing materials incidentally right you may disturb those things incidentally right this is the the classic veneer scenario you're gonna see on the board is you're gonna see like a plumber that is caught in through a wall to you know access a pipe and you know inadvertently disturbs as best of like an asbestos containing like joint compound or ceiling top right the worker did not intend to disturb asbestos but he did that's gonna be class three and then class four is basically people that do custodial work in areas where there is asbestos containing material right so like for example you're sweeping up debris near asbestos containing materials you are cleaning up areas you know we're class one or class two work has occurred right is the lowest risk but it's still regulated right class four honestly just only requires like two hours a best asbestos awareness training and that number is definitely more testable not certainly know that if I were you right so again let's kind of summarize remember again class one TSI and surface in ECM removal right so the classic example is like you kn

ow a baiting pipe insulation you're gonna need 32 hours of a full asbestos abatement course right at least the supervisor right and then class two is if you're doing other ECM removal that is not TSI or surface material right so you know like for example like floor tile or you know removing overroutine this requires a 16 hour course at the minimum and then class three is repair maintenance you know incidental disturbance so like for example the classic board question is a plumber that is cutting through an ECM will that requires a 16 hour course as well and then class four is just custodial work near ACM right so like for example you're sweeping near ACM near asbestos debris this requires two hour awareness training okay so again remember the class four 12 hour awareness training number the love to test it right class order workers class four remember forty by two is two that may be a nice way to remember remember that right so let's look at a class three scenario let's let's give let's give an example right so let's see you have a 45 year old maintenance worker right is repairing a leaky pipe in a you know like a 1960s office building and then as it's cutting through the drywall to assess the pipe he he disrupts the joint compound right disturbs the joint compound and that thing is found to contain like 2% of crystal talas best is right wasn't wearing respirator protection at the time what class of work did this represent and what should the employer have done well it's class three work right is class three work incidental disturbance of ACM you know during repair and maintenance right the employer should have done a hazard assessment before the work began right and if you know ACM was identified or assumed you know in this circumstance the worker should have been provided with respiratory protection you know like a half-face APF 10 respirator right and you should ha

ve also use wet methods right to you know prevent the person from you know again be next at least minimize as best of exposure right and a competent person should have been designated and I'm going to talk about what a competent person is in a bit right so the next thing I think I want to discuss here is medical surveillance right who qualifies for medical surveillance with asbestos and what does it include what does it include right so the thing is medical surveillance is one here that the boards they just love to test your knowledge of specific thresholds right so let's walk through exactly who qualifies who is gonna qualify for medical surveillance again what's the enrollment trigger well again an employee must be enrolled in any one of three conditions right so anyone of three conditions replies right so number one if you have exposure out of above the action level right again 0.1 fibers per cubic centimeter for 30 or more days per year you enrolled right that 30-day threshold is very important right so if a worker is exposed above the action level on 29 days per year technically that doesn't meet the threshold right although in practice you'd probably want to enroll them anyway right just better save than sorry but the threshold is 30 days right what's the second trigger second trigger is the worker is required to wear a negative pressure respirator the worker is required to wear a negative pressure respirator right so this includes you know half-face full-face APF 10 respirators right even if they are measured exposure is still below the action level the physiologic demand of the respirator wear is enough to require medical clearance right so that's something you definitely need to know now what's the third trigger the third trigger is you have a worker that has evidence of asbestos related disease on a prior exam right once they're in the program they stay once

they have evidence of asbestos related disease they basically stay in this medical enrollment program right so please again this the 30th per year threshold that is costly boards material they love to test it right and then remember again negative pressure respirator use that's an independent trigger regardless of the measured exposure right so please keep that in mind so what does the exam entail what does this exam actually entail well the thing is it typically includes like you know detailed occupational medical history like you do for any patients that you see right you know we're gonna focus on respiratory symptoms prior asbestos exposure right and then you're gonna do a physical exam and you're gonna emphasize the respiratory system right and then you're also gonna do PFT's preliminary function testing gonna check out the FEC the FVV1 right and you're gonna do an a chest X-ray using the ILO classification system right the international labor organization classification system I'm gonna talk about that in the in the next segment although I'm not gonna go too deep in the weeds on that because that's not crazy testable right so one thing I want to say though is kind of a confidentiality point that the boards love to test right so the thing is the physician his job is to provide a written medical opinion to the employer but that opinion is actually very limited right the employer the only thing the learner is hey whether the worker is medically fit for the job whether they're any limitations whether the worker was informed of the results right well the actual diagnosis right so what does the employer get right the only learning the worker is medically fit for the job whether there's any limitations whether the worker was informed of the results right well the actual diagnosis like hey asbestos is plural plaques whatever they found that's kept confidential that's be

tween the physician and the worker okay so again the written medical opinion to the worker contains only fitness for duty information right specific diagnosis those are completely confidential to the worker right so again let's run through these enrollment triggers really quickly again again if you have exposure out of above the action level right again the threshold is 0.15 per CC for 30 or more days per year right if you use a negative pressure respirator any kind of use regardless of exposure level triggers medical enrollment right if you have prior asbestos related disease any prior positive finding then yes you're gonna be on the medical enrollment right so now let's talk about chest x3 frequency I think that's kind of like a big thing to actually know for your for your boards right so the chest x3 frequency right the ILO table right we're gonna talk about this right this is probably like honestly one of the highest yield tables in you know that you should know for your exams I'm gonna kind of work through it logically in the way that we help you remember it right so ocean doesn't just say get a chest x3 tells you exactly you know how often right and it's based on two variables they are two variables that determine this they are two variables that determine this the workers age and the number of years since your first asbestos exposure your age and the number of years since your first asbestos exposure right so understanding how these two variables interact is actually very helpful if you want to answer veneer questions correctly right so so what's the logic what's the rationale behind this what's like the logic behind this what the thing is this right the thing is the risk of asbestos related disease that can be detected on radiography is going to increase with both age and cumulative exposure time right so the thing is this surveillance interval is pretty much

titans right so you know x-rays being ordered more frequently as both of those factors increase your age and your length of exposure to asbestos right so the interval never gets shorter than one year will always be a year at least a year right and it only titans when both conditions are met you know the worker is you know 45 or older and you know has at least you know 10 years since their first exposure right so I'm gonna give you like the way I remember the table right so I remember three age ranges three age ranges that's the first thing should remember less than 45 45 to 54 and 55 or greater I'm gonna say that again memorize three age ranges less than 45 45 to 54 and 55 or older okay and then remember less than 10 so we've talked about the ages right that's the first variable second variable is the year since first exposure the year since first exposure okay the year since first exposure memorize three ranges less than 10 years 10 to 19 years and 20 years or more okay less than 10 years 10 to 19 years and 20 years or more okay and then I want you to remember these two numbers 555 521 555 521 555 521 if you remember this you're golden you're golden right so again let me kind of break this down right so I said memorize three age ranges each less than 45 45 to 54 and 55 plus and then for year since first exposure less than 10 years 10 to 19 years 20 years or greater and then what do I mean by 555 521 555 refers to the number of years so now is almost like you've made like a almost like a three by three table in a sense right the ages are the top and then the screen the year since first exposure on the left side right 555 just means hey how frequently do you get a chest x-ray for the less than 10 year bracket right it's five years for people under 45 5 years for 45 to 54 5 years for 55 plus 555 right but obviously when it's 10 to 19 years it's gonna be more frequent th

at's where the 521 number comes in it's five years for the less than 45 people it's two years for the 45 to 54 people and it's one year for the 55 plus folks and then maybe wondering divine but there was a third part here where it's been if it's been 20 plus years since your first exposure well guess what that also has the same intervals as the 10 to 19 years it's also 521 so five years for the under 45 two years for the 45 to 54 and then every year for the 55 plus group that's it if you know that you're good to go you are good to go you are good to go okay so again remember the tightening of the interval occurs when you're both over 45 or more right on your years of exposure you know 10 or more years right 10 or more years right again either fracture alone doesn't tighten the interval right both that take it into consideration right so let's let's me do a few veneers just to really really cement this information in your brain right so let's say they give you a question about a 42 year old insulation contractor right that was first exposed to us best was at each 22 right he has 20 years of documented exposure right how often should he receive a chest x-ray or think about this it should be every five years right again this person has been exposed for 20 years but his age is still under 45 right so the interval is five years for literally everything right again age is like the getting factor when the worker is young right this is another veneer so what if they give you a 48 year old sheepyard worker exposed first at each 35 right and you know you told that he has 13 years since his first exposure how often should he receive a chest x-ray well it should be every two years if you every two years right because number one he's in the 45 to 54 each bracket right so it's in the middle he's in the middle right and he has 10 to 19 years since first exposure remember five to one

he's in the middle right so both conditions are met so interval tightings to every two years right and then what if they give you a question about like a 58 year old construction worker first exposed at each 28 right and he has 30 years since his first exposure how often should he receive a chest x-ray it should be every year right think about it is 55 plus right and he's had 20 plus years since exposure remember five to one number one remember the one is at the end right so this person is going to get the maximum surveillance and frequency right and then what if they give you a question about like a 56 year old facilities manager you know first exposed to us besters at age 52 you know during like a building or innovation project right and you're told that oh he has like four years since his first exposure how often should he receive a chest x-ray what do you think I hope you're saying divine it's going to be every five years going to be every five years right he's 55 plus but he has fewer than 10 years since first exposure remember five five five five five five right so again both conditions must be met look at the age and the frequent and the when every answering these questions look at the age and length since first exposure right so again age alone is not sufficient right so this age alone is not sufficient to tighten the interval you need both consider both right so this person is going to be every five every five years right now a common board veneer trap right common board veneer trap is again they'll give you an older person with a short exposure history right and see if you you're incorrect in tightening the interval right again the answer is going to be every five years if you're a person that's older 55 plus you're exposed for less than 10 years the interval is every five years right now the thing is I'm going to talk about the iLOB reading again I'm going

to talk about it very cursory detail you don't need to know this crazy detail for your for your exams right but the thing is usher this specifically required that the extra read using the interlational labor organization a system right and the reader must must be a be reader right it basically is a physician certified by NIOSH in iLO classification right not just any radiologist a be reader right and what does this system use well it basically grids per and come along pass it is by shape and size right so you know ST and U for irregular opacity right you know which is what you basically see in as best as best doses right and PQR for rounded opacity right so STU likes to for irregular opacity and then PQR for rounded opacity right plural changes those are greater completely separately right but the key thing to know here is if you have a finding of one zero greater for per and come along opacity that's generally the threshold for a positive film right does a positive film you need to be referred to a pulmonologist at that point right and one word you may see is this word called profusion profusion profusion PROFU SION right it's basically the iLO term for the density of opacity for the density of opacity right higher profusion means you have much more advanced disease right so again remember please iLO reads must be performed by a NIOSH certified a be reader okay by a NIOSH certified a be right now let's talk about the spectrum of disease with as best doses and you know the interaction between smoking and as best dose right so let's kind of you know anchor the regulatory content to clinical diseases right you need to know the five major you know as best dose related conditions you definitely need to know them for your exams you know want to know the latency periods right and you want to know the distinguishing features right so as best doses is what we're going to tal

k about right so the latency is 10 to 20 years right what are you going to see well you're typically going to see like bilateral bisler you know interestingly fibrosis right so remember as best dose affects the base of the lungs not the apex the base the base most of the pneumoconylces do the apex of the lungs when as best dose does the base right and you know the this is dose-dependent right typically that's going to require heavy long term exposure right now misotheliuma the latency is like 20 to 40 years right typically it's going to involve the plural you know the plural lining sometimes they actually involve the period to nail lining right and remember as best dose is much much greater than smoking as a cause in fact let me tell you this smoking basically does not increase your risk of misotheliuma on the board exams it's as best dose is as best dose that increases that risk right and there's no dose threshold right even brief exposure to as best dose can increase your risk of misotheliuma right and then long cancer right the latency is about 15 to 35 years right and there's a multiplicative risk with smoking right so as best dose resists your risk by like 10 fold smoking by like you know five to nine fold right so there's like a 50 to 90 fold increase risk of long cancer if you have as best doses and if you're exposed to as best dose and you smoke right in fact like whenever you see a physician for for for an exam and you're expressed as best dose expose they tell you that hey smoking not good for you smoking not not good for you right and then also a plural plucks right plural plucks the latency can be anywhere from 10 to 30 years right so typically you're gonna see like you know just all these parietal plural plucks many times they're calcified this is usually a marker of exposure to as best dose right it does in it's not pretty malignant it's just a marker of

as best dose exposure right and then one thing I want to mention is that what is the earliest finding this is number five what is the earliest finding in a person that has been exposed to as best dose right the earliest long finding you may see it's gonna be a benign plural infusion it's gonna be a benign plural infusion that's actually pretty high yield to know for you exams right that's actually pretty high yield to know for your exams pretty high yield to know for your exams right and again remember misotheliuma like I said has no dose threshold right they love to test this in on the on the op-made boards right has no dose threshold right so if a person was a shaper worker very brief as best dose exposure decades ago they can still develop misotheliuma there's no safe level right this is very different from as best doses right which requires you know very heavy you know very prolonged exposure right and then again don't forget that multiplicative risk between smoking and lung cancer between smoking and as best dose right really really jucks up your risk of lung cancer it's one of those multiplicative relationships that exist in bio statistics right so usually keep keep this in mind for for your exams right so what if they give you a question about like a 62 year old you know former you know boiler maker presents for evaluation right and you're told that hey he was heavily exposed to as best dose in a shape yard from age you know 25 to 45 right and he has smoked one pack pretty for 30 years equally at age 55 right what's the most important intervention you you you you you you know that he should have been offered during his working years and why the most important intervention should have been a smoking cessation canceling right because the thing is again smoking and as best dose the interact multiplicatively for for your risk of lung cancer right so if you elimina

te the smoking component because it's multiplicative remember there's a difference between 10 times five and 10 plus five right 10 plus five is additive that's 15 10 times five is 50 right whenever something is being multiplied big big big big big extreme effects right so the thing is if you eliminate the smoking component that dramatically reduces the person's absolute risk right so this intervention is going to have a much greater impact in as best dose related workers than than in the general population right so keep that in mind now as we begin to slurry up of the spot guess I'm going to talk about the different fiber types for as best dose they do like to talk about it on the exams right so remember it's a conceptual anchor it's think of it more conceptually than train to memorize this right so the thing is there are two major categories of asbestos fibers right there's the serpentine fibers and there's the amphibules the serpentine fibers and the amphibules right so crystal tal is honestly the only commercially significant serpentine fiber you should know right it's basically wide as best dose right it basically accounts for about 95% of all the asbestos that has ever been used commercially right and it's it's kind of curly right and because it's curly it makes it easy for the lungs to get rid of it right so the mucus ciliary system of the lungs can get rid of it pretty efficiently over time right although don't get me wrong crystal tal right CHRYSOTILE right very strongly as still strongly as rid of asbestosis and lung cancer but it's considered somewhat less potent because again it can it can be got rid of pretty pretty easily right now what is the big scary one those are the amphibules a mp hi b o l s right these are things like crusido light amocytes tremolite and thofelite atino light right these are like the collard asbestos fibers right the blue and the b

rown asbestos types right they're straight the aridget the very bio persistent right so they sting the long for decades they don't go anywhere right and honestly of all these things I mentioned all the lights and lights and lights I mentioned the big one should really know is crusido light CRO CIDOLIT that's the blasbestos that's the most carcinogenic most strongly as rid of misotheliuma right if a shipyard even vineyard mentions a shipyard work or a nevel insulation you know from the 50s through the 70s think of high dose amphibule exposure think of high dose amphibule exposure okay think of high dose amphibule exposure right so again remember crusido light blasbestos that is the most carcinogenic most carcinogenic right most strongly as rid of misotheliuma right crystal towel is like 95% of you know commercial use right amphibules tend to be bio persistent right those are kind of big things to know for your for your exams okay now so let's you know just to kind of wrap this up let's talk about some controls some housekeeping and the EPA how does the EEP because the EP actually has an integration with the OSHA as best to standard so let's kind of kind of walk through this right so the thing is remember your controls right this is very heavily commonly tested on the boards right so remember you know local exhaust ventilation with methods to suppress you know the release of fibers using HEPA vacuums for clean upright HEPA vacuums for clean up right and please I want to maybe make a quick stop here right this is a classic board strap you never use a regular vacuum to clean up asbestos use a HEPA vacuum use what a HEPA vacuum right so standard vacuums they're going to release the fibers back into the air through their exhaust right it's only a HEPA filter vacuum that is appropriate for asbestos clean up right and again remember respirators they come after engineering con

trols are maximized right so please regular vacuums are prohibited for asbestos clean up you got to use HEPA filter at vacuums okay this is one of the most commonly tested board boards wrong answer choices on the boards right so in terms of uh uh with the disposal right so the thing is if you want to dispose of asbestos you need to dispose of it in impermeable labeled bags impermeable labeled bags right and they're going to have OSHA and EPA asbestos running labels they're going to have OSHA and EPA asbestos running labels right no dry sweeping no compress air for cleaning no right and again remember you you need to know the EPA side of this this whole equation right so again remember OSHA governs worker protection but the EPA they have their own asbestos regulation under something known as Nishap Nesap Nesap right that alphabet sub just means you know the national emission standard for hazardous air pollutants right we find that in 40 quote of federal regulations part 61 right so if you're renovating or you know doing demolition of you know buildings we've regulated asbestos containing materials the building owner the building operator they must notify the appropriate state environmental agency at least at least 10 working days before the begin work at least 10 working days before the begin work right so this is the EPA OSHA integration that they love to test on the boards right so again remember OSHA protects workers but EPA through their Nisha program right air emissions building demolition you know you need to notify at least 10 days 10 working days 10 working days advanced notice to the state agency before you renovate or demolition and ECM continue to build it all right so again please just make make make sure you know this stuff right make make sure you know this stuff remember again the PEL 1 fiber per cubic centimeters right it's also the same thing as the ac

tion level over a liter or a time-weighted average right the construction standard is more frequently tested than the general industry standard right remember class vocal studios right two hours awareness training that's a testable number they love to test it right again for surveillance enrollment 30 days per year right if you use negative pressure respirators right that's an independent surveillance right and again remember the chest x-ray frequency tightens only when age is 45 or greater and your years of exposure is 10 or greater right both are required right and then remember and ILOB readers required not just any radiologist right mesothelioma there's no dust threshold right any kind of asbestos exposure if you short brief can increase your risk of mesothelioma right smoking asbestos you know long cancer risk is multiplicative is not a dead aditive right a proplox are not pretty malignant they're just a marker of asbestos exposure remember the first finding on a chest radiograph in a person that's been exposed to asbestos is a benign plural effusion a benign plural effusion right then remember uh cross-seedolite C-R-O-C-I-D-O-I-L-I-T-E is the most carcinogenic asbestos fiber right and remember you can only use hepa vacuums regular vacuums are prohibited for asbestos cleanup right and then remember the EPA knee shot right again 10 working days notice before you do any demolition or innovation of of a building that contains asbestos container material right again i just kind of put this high-youther up it review at the end to kind of tie things together for for you right so this is the end of this podcast again i really hope you found this to be helpful um so just study this material shows up a lot on the boards right i won't be going over it if it was not boards relevant right so i'll see you god willing in a episode uh in the next uh ombr uh podcast right it's g

onna be ombr s3 right where i talk about something else that is augment boards testable all right so thank you have a wonderful day god bless you and bye for now thank you

General Industry ($29 \text{ CFR } 1910.1001$) and Construction ($29 \text{ CFR } 1926.1101$). The construction standard is more heavily tested.

1) Exposure above the Action Level (0.1 fibers/cm$^3$) for $\ge 30$ days/year; 2) Requirement to wear a negative pressure respirator; or 3) Evidence of prior asbestos-related disease.

A HEPA filter vacuum. Standard vacuums are prohibited as they release fibers through their exhaust.

Class 3 work, which requires repair and maintenance activities where ACM may be encountered incidentally.

Crocidolite (blue asbestos). It is highly persistent and strongly associated with mesothelioma.

At least 10 working days, reported to the state environmental agency under the EPA's NESHAP program.

$0.1 \text{ fibers/cm}^3$ as an eight-hour TWA.

Periodic air monitoring and mandatory medical surveillance enrollment.

Removal of Thermal System Insulation (TSI) and surface AC Ms; this is the highest risk category requiring full containment and a competent person on site.

STU.

Mesothelioma has no known dose threshold; even brief exposure can increase risk. Asbestosis requires very heavy/prolonged exposure.

Crocidolite (blue asbestos).

$0.1 \text{ fibers/cm}^3$ as an eight-hour TWA.

Periodic air monitoring and mandatory medical surveillance enrollment.

Removal of Thermal System Insulation (TSI) and surface AC Ms; this is the highest risk category requiring full containment and a competent person on site.

STU.

Mesothelioma has no known dose threshold; even brief exposure can increase risk. Asbestosis requires very heavy/prolonged exposure.

Crocidolite (blue asbestos).