Presentation on theme: "SIZE-SELECTIVE SAMPLING OF PARTICULATE MATTER FOR OCCUPATIONAL HYGIENE"— Presentation transcript:
1 SIZE-SELECTIVE SAMPLING OF PARTICULATE MATTER FOR OCCUPATIONAL HYGIENE Presented by SKC Inc.
2 AIRBORNE PARTICLESInclude solid and liquid matter such as:Dusts-solid particles that become airborne during crushing of rock-like materialFumes-microscopic particles generated during welding and other operationsMists-liquid droplets in airSmokes-particles generated from incomplete combustion or burningAirborne particles include a variety of solid and liquid matter that are defined in this slide:Although the term DUST is used generally to describe particulate matter, TECHNICALLY dust is defined as solid particles generated during actions like crushing of rock-like material.Fumes-are microscopic particles generated during welding and similar operations (Despite what we hear on TV news reports, people are not overcome with CO FUMES. CO is a gas).Mists-liquid dropletsSmokes-particles generated from incomplete combustion
3 CLARIFICATIONSThe word dust is used in the occupational health and safety profession and throughout this training module as a general term for particulate matter and airborne particles. Do not be confused by the general use of this term.Asbestos and other fibers are also hazardous particulate matter found in the workplace. Fibers however will not be covered in this training module.As a point of clarification, please note that I will use the term DUST to describe particulates in general. So when you hear me say “dust” in this webinar, I am not referring to the strict technical definition of dust given in the previous slide.Also, note that asbestos and other fibers are also hazardous particulates found in the workplace. But I will not discuss fibers in this training module since “size-selective” sampling of fibers is not done.
4 HEALTH EFFECTS OF AIRBORNE PARTICLES Are determined by three parameters:Chemical Composition-What is the chemical makeup of the particulate matter?Mass Concentration-How much particulate matter is being inhaled by exposed persons?Size Characteristics-How big are the individual particles?As is.
5 PARTICLE SIZE: A CRITICAL PARAMETER The size of the airborneparticles will determine wherethey will deposit in therespiratory system. Smallerparticles are more hazardousas they will deposit deep intothe lower regions of the lungand can enter the bloodstream.Particle size is a very important factor in determining WHERE particles will deposit in the respiratory system.Smaller particles are of critical concern since they will deposit in the lower regions of the lung and can enter the bloodstream.
6 PARTICLE SIZE: DETERMINES HEALTH EFFECTS Governmentregulations andexposure guidelineshave been issued forsome compounds basedon their particle size.These size-selectiveexposure limits specifydifferent allowablelevels for smaller versuslarger particles of thesame material.Because particle size plays an important role in the health effects, government regulations and exposure guidelines are issued for some compounds BASED ON THEIR PARTICLE SIZE.These so-called size-selective exposures limits specify different allowable levels for smaller versus larger particles of the same material.
7 DEFINING AND MEASURING PARTICULATES IN THE OCCUPATIONAL ENVIRONMENT TRADITIONAL APPROACHLet’s now look at how particulates in the occupational environment are defined and measured.We’ll start with the older, traditional definitions and samplers.
8 PARTICULATES IN THE WORKPLACE Have traditionally been defined as:TOTAL DUSTRESPIRABLE DUSTTraditionally, particulates have been defined as either total or respirable dust.
9 TOTAL DUSTIs collected by using a filter of a type and pore size as specified in the published sampling and analytical method for that compound.The filter is loaded into a cassette and connected to a sampling pump that has been calibrated to a flowrate of at least 1 L/min.Samples are collected in a fixed point location or in the breathing zone of workers.Total dust is collected using a designated filter that is loaded into a 37-mm cassette. Using typical flow rates of 1-2 L/min, a pump is used to draw air through the filter for sample collection.This technique is used for personal or fixed point (area) samples.
10 37-mm FILTER CASSETTE WITH FILTER Outlet of CassetteSupport PadHere you can see the schematic of a traditional 37-mm filter cassette loaded with a filter.The inlet of the filter is typically pointing DOWN during sample collection. In this way, the collected dust represents what the pump actually PULLED into the filter cassette and not what landed onto the filter due to gravity or due to impaction from activities in the workplace.FilterInlet of Cassette
11 TOTAL DUST SAMPLING IN THE BREATHING ZONE A reference method for total dust sampling is NIOSH Method 0500 entitled:Particulates Not Otherwise Regulated, Total.In this method, a PVC filter is placed into the breathing zone for sample collection and then is analyzed gravimetrically.Reference NIOSHMethod 0500
12 RESPIRABLE DUSTIs also collected onto a filter of a type and pore size that is specified in the sampling and analytical method for designed compounds.Preceding the filter, however, is a size-selective sampler such as a cyclone that will separate the respirable fraction from the non-respirable fraction when connected to a pump sampling at the designated flow rate for that specific device.Like with total dust, respirable dust is also collected onto filters to evaluate exposure levels.Preceding the filter however is a SIZE-SELECTIVE SAMPLER that will separate the smaller respirable fraction from the larger non-respirable fraction.Cyclones are most commonly used for size-selection of respirable dust, but impactors are also available from SKC for respirable dust sampling.
13 RESPIRABLE DUST SAMPLING WITH CYCLONES A primary method for respirable dust sampling is NIOSH Method 0600 entitled:Particulates Not Otherwise Regulated, Respirable.The method lists (3) cyclones as options for separating the respirable from the non-respirable fraction. The SKC aluminum cyclone at 2.5 L/min is one of the options listed in this method. After passing through the cyclone, respirable dust is collected onto PVC filters for analysis.Reference NIOSHMethod 0600
14 CYCLONE OPERATION Function on the same Large (non-respirable) principle as a centrifuge.When the air comes inthrough a small slitopening on the side,cyclonic action occurswithin the stem of thesampler.Large (non-respirable)particles hit the side of thecyclone and fall into thecap (grit pot) at thebottom of the cyclone andare discarded. Smallerrespirable particles arethrown upwards onto thefilter and are analyzed.Read slide as is.
15 DEFINING AND MEASURING WORKPLACE PARTICULATES NEW CONCERNS, DEFINITIONS, AND SAMPLERSNow let’s discuss NEW ISSUES in defining and measuring workplace particulates. Specifically, we will address:New sampling CONCERNSNew Particulate SIZE FRACTIONS andNew SIZE-SELECTIVE SAMPLERS .
16 NEW CONCERN WITH TRADITIONAL FILTER CASSETTES US NIOSH and OSHA scientists have been addressing sample losses with traditional 37-mm filter cassettes.Of particular concern, are sample losses that occur from particles that adhere to the interior cassette walls and are not analyzed.A concern that US NIOSH and OSHA have been addressing recently is sample loss with traditional 37-mm filter cassettes.This sample loss is the result of particles that stick to the side of the cassette and are never analyzed.
17 OSHA STATEMENT: HEXCHROME METHOD ID 215; VERSION 2 “Tests showed that Cr (VI) equivalent to 0 to 123% of the amounts found on the PVC filter were present on the interior walls of cassettes used for compliance samples. It is now routine procedure to wipe interior walls of sampling cassettes for all metal samples analyzed.”In the latest version of the OSHA method forhexavalent chromium, OSHA points out that:More hexchrome can sometimes be found onthe side of the cassette than on the filter itself!!To address this concern, it is now a routineprocedure for OSHA to (not just rinse but) to alsoWIPE the walls of the cassette for ALL metalsamples analyzed.Source: United States. Occupational Safety and Health Administration.Hexavalent Chromium Apr 2009 <http://www.osha.gov/dts/sltc/methods/inorganic/id215_v2/id215_v2.html>
18 NIOSH STATEMENT IN AIHA JOURNAL ARTICLE Dust deposits on the walls of filter cassettes were 19% of the total sample for lead and 25% of the total sample for copper.Filter cassettes should be rinsed and wiped prior to analysis.NIOSH reported similar findings in a September 2007 AIHA/ACGIH journal article and they concur with OSHA’s directive to wipe the inside of cassette walls for analysis.Source: Ashley, Kevin, Harper, Martin and Demange, Martine.“Concerning Sampler Wall Deposits in the Chemical Analysis of Airborne Metals.” Journal of Occupational and Environmental Hygiene 4:9 Sept 2007: D81 - D86 <http://dx.doi.org/ / >
19 ACCU-CAP EMERGES TO ADDRESS CONCERNS Filter insert that is placed into a 2-piece cassette with support pad.Consists of a clear plastic dome heat-sealed to a filter.Dust is collected onto the filter or within the dome for gravimetric analysis.A newer sampler called the Accu-cap has emerged to solve the problem of cassette wall losses. The Accu-cap is simply a filter insert that is placed into a 2-piece cassette with support pad for use.The Accucap consists of a clear plastic dome that is heat-sealed to a PVC filter. Dust is collected onto the filter or within the dome for gravimetric analysis.SKC GLAPVC Filter
20 A NEW SOLU-CAP EMERGES IN 2013 Designed for the measurement of metals using chemical analysisAcid digestible dome material heat sealed to mixed cellulose ester filterPre-loaded into 2-piece cassettes with support pads (SKC )Eliminates the need to wipe the inside of the cassette for analysisEnsures all collected sample is analyzedIn 2013, a new sampler emerged based on the Accucap design.The new sampler called the Solu-cap is designed for measurement of metals using CHEMICAL ANALYSIS. The Solu-cap has a dome material that allows for acid digestion by the laboratory and analysis using standard methods. The dome is heat sealed to a mixed cellulose ester filter for sample collection.The Solu-cap eliminates the need to wipe the inside of the cassette for analysis and ensures all collected sample is analyzed.
21 NEW SIZE FRACTIONS FOR PARTICULATES Many occupational hygiene agencies andstandard setting bodies around the world haveabandoned the 2 traditional sizefractions of total and respirable dustand have instead defined 3 particulate sizefractions.Another new issue is how occupational hygienists DEFINE particulate size fractions.As is.
22 NEW SIZE FRACTIONS FOR PARTICULATES Note that U.S. OSHA and MSHA have not adopted these new size fractions for particulates. They still measure and regulate total and respirable fractions.ACGIH has adopted these new size fractions for their Threshold Limit Values (TLVs®).Inhalable Particulate MatterThoracic Particulate MatterRespirable Particulate MatterAt this time, particulates are often defined in terms of:InhalableThoracicand RespirableParticulate mass.Note that in the U.S., OSHA and MSHA have not officially adopted these new size fractions, but ACGIH does indeed use these new terms for their threshold limit values.
23 particulate fractions adopted by most occupational hygiene Illustrationof the 3 newparticulate fractionsadopted by mostoccupational hygieneorganizations andstandard setting bodiesaround the worldincludingACGIH, ISO, and CEN.Here you can see an illustration of the 3 new particulate fractions.Inhalable particulate is material that is hazardous when deposited anywhere in the respiratory system (including nose/mouth).Thoracic particulate is hazardous material deposited within the lung airways and DOWN TO the gas exchange region of the air sacs.Respirable particulate is that deposited within the gas exchange region.
24 NOTES ABOUT CUT-POINT You will frequently see the term 50% or median cut-point used todescribe the performanceof size-selective samplerslike cyclones. It isimportant to understandthis term.When doing size-selective sampling, you will frequently see the term 50% or MEDIAN cut-point used to describe the PERFORMANCE of sampling devices like cyclones.It is important that you understand this term.
25 NOTES ABOUT CUT-POINTSampling devices are not 100% efficient in collecting all sizes of particles from microscopic fumes to large dusts.The particle size that the sampling device collects with a 50% efficiency is described as the 50% or median cut-point.AS IS
26 CONSIDER A VACUUM CLEANER Vacuum cleaners do not pick up all sizes of particles with the same efficiency.A vacuum cleaner may be 100% efficient in collecting a small piece of dust; 0% effective for a big stone.There is a size where the vacuum is 50% efficient.To help understand 50% cut-point, consider the performance of a vacuum cleaner. Vacuum cleaners do not pick up all sizes of particles with the same efficiency.Read last 2 bullets.
27 NOTES ABOUT CUT-POINTA size-selective sampler will always have the 50%cut-point specified for a designated flowrate.Particles smaller than the 50% cut-point will be collected with an efficiency greater than 50%.Particles larger than the 50% cut-point will be collected with an efficiency less than 50%.AS IS
28 INHALABLE PARTICULATE: A NEW PARTICULATE SIZE-FRACTION The new term for total dust.Is defined as dust that is hazardous when deposited anywhere in the respiratory system including the nose and mouth.Is collected using a sampler designed and tested to capture this size of particulate matter.Inhalable samplers have a 50% cut-point of100 um.Let’s next review a new particulate size-fraction called inhalable particulate mass.Inhalable particulate is essentially “the new total dust” .It is defined as ….AS IS
29 IOM SAMPLER: A GOLD STANDARD FOR INHALABLE DUST The very first sampler designed to meet the new criteria for inhalable dust was developed at the Institute of Occupational Medicine in Scotland and is named the IOM sampler.The IOM Sampler was licensed for manufacture by SKC Ltd in the UK and it is the Gold Standard for inhalable sampling. The IOM is specified by name in many international standards and published methods.SKC A
30 USING THE IOM SAMPLER: GRAVIMETRIC ANALYSIS Load a 25-mm filter into the cassette using forceps and wearing gloves.Equilibrate the filter/cassette assembly overnight under controlled conditions, then weigh them as a unit.Collect the sample at 2 L/min.Equilibrate and weigh again for sample analysis.To use the IOM sampler for gravimetric analysis:First, load a 25-mm filter into cassette.Then, EQUILIBRATE the filter/cassette overnight under controlled conditions of temp/humidity and weigh them as a unit.Do not dessicate the cassette/filter assembly.Collect the sample at 2 L/min and then after sampling, equilibrate and weigh again for analysis.
31 THE IOM ADVANTAGE: NO SAMPLE LOSS Since the filter and cassette are weighed together, all particles which are drawn in through the sampling inlet are part of the analysis.Any particulate dislodged from the filter due to accidental knocking, will be retained inside the cassette and weighed.The IOM ensures users the advantage of NO sample loss.Read slide.
32 USING THE IOM SAMPLER: FOR CHEMICAL ANALYSIS For this application, the stainless steel cassette is frequently used.The stainless steel cassette is often preferred since the lab will use chemical solvents to rinse the cassette for analysis.For chemical analysis of metals and other compounds, the IOM with the SS cassette is frequently used.The SS cassette is often preferred since the lab will RINSE the cassette with CHEMICAL SOLVENTS in this procedure.
33 IOM SAMPLER FOAM DISCS: FOR SIMULTANEOUS INHALABLE AND RESPIRABLE SAMPLING Multi-Dust Foam DiscsDeveloped by the UK Health and Safety LaboratoryA foam plug (SKC ) is inserted into the IOM cassette in front of the filterLarger particles are trapped in the foam plug; smaller particles in the filter.Dust collected on filter only is the respirable fraction. Filter plus foam is inhalable fraction.In the European hygiene community, there is a great interest in the use of polyurethane foams for size-selective sampling of particulates.In recent years, the UK Health and Safety Laboratory developed polyurethane foam discs that are inserted into the IOM cassette for simultaneous sampling of inhalable and respirable dust.Note: The dust on the filter only is the respirable fraction. The dust on the filter PLUS the foam is the inhalable fraction.
34 IOM SAMPLERS FROM SKC Plastic Sampler with Plastic Cassette- SKC ALightweight for gravimetric analysis.Plastic Sampler with Stainless Steel Cassette-SKC ASuitable for chemical or gravimetric analysis.In summary, there are three models of IOM Samplers from SKC:Plastic sampler with plastic cassette for gravimetric analysisPlastic samplers with SS cassette for chemical or gravimetric analysis of the sample
35 IOM SAMPLERS FROM SKCStainless Steel Sampler with Stainless Steel Cassette-SKC ACan be autoclaved for bioaerosol sampling.Or a stainless steel SAMPLER with a SS cassette.This is a specialty item normally used only forbioaerosol sampling or EXTREME staticconditions due to the cost and weight.
36 ALTERNATIVE INHALABLE SAMPLER Button SamplerInlet has a screen to keep out large, non-inhalable particles.Uses higher flow rate which enhances sensitivity of measurement for compounds with low exposure limits.Since the development of the IOM sampler in 1986,other inhalable samplers have emerged. Shownhere is a sampler developed by researchers at theUniversity of Cincinnati called the Button Sampler.The Button Sampler has a screen over the inlet tokeep out non-inhalable particles that may becomeairborne during workplace activities. The ButtonSampler uses higher flow rates than the IOM whichhelps in the measurement of compounds with VERYlow OELs.SKC
37 USING THE BUTTON SAMPLER: SAMPLE LOGISTICS Unscrew the sampler inlet and remove the O-ring.Place a 25-mm filter on the stainless steel support screen, replace the 0-ring and the sampler inlet.Collect the sample at a flowrate of 4 L/min.After sampling, remove and transport the filter only to the laboratory.Note that there is no cassette with the Button Sampler. The filter is placed directly onto a stainless steel support screen for sample collectionNote also that the Button Sampler has a flow rate of 4 L/min (compared to 2 L/min for the IOM). So this enhances the sensitivity of measurement for compounds like beryllium with a very low TLV..
38 USING THE BUTTON SAMPLER: SAMPLE LOGISTICS A filter with a pore size of 1.0 um or larger is recommended to keep pressure drop low.Otherwise, the pump may fault with any accumulation of sample on the filter due to excessive backpressure.Since there is no cassette with the Button Sampler, users will need to have a device to transport the filters with collected sample to the laboratory.Options include conductive filter transport cases (SKC ).Shown on this slide are 2 very important considerations when using the Button Sampler:First-you must use a filter with a pore size of 1 micron or larger. Otherwise, at the required flow of 4 L/min, your personal pump may fault with any dust accumulation due to backpressure issues.Next-since there is no filter cassette, you will have to have a secure device to transport your filter sample to the lab. SKC offers filter transport cases or filter keepers for this purpose.
39 TIPS ON CALIBRATIONSKC offers calibration adapters that allow the IOM and Button Samplers to be directly attached to external flowmeters including the Defender primary flow calibrators.CALIBRATION ADAPTERfor the IOM Sampler is SKCfor the Button Sampler(shown here) isSKCIt is generally preferable to use a calibration adapter to assist in flow measurement.SKC offers calibration adapters that allow the IOM and Button Samplers to be directly attached to external flowmeters including the Defender primary flow calibrators.
40 THORACIC PARTICULATEDefined as those materials that are hazardous when deposited anywhere within the lung airways and the gas-exchange region.Thoracic samplers have a 50% cut-point of10 um.The next particulate size fraction that we will discuss is Thoracic Particulate Matter.As discussed previously, the first bullet on the slide shows the definition of thoracic particulate.Note also that thoracic samplers have a 50% cut-point of 10 micron.Thoracic region includes bronchioles as well as air sacs in the lower lung.
41 THORACIC TLVs AS OF 2014 Sulfuric acid-TLV Cotton Dust-TLV of 0.2 mg/m3 asthoracic particulate.Cotton Dust-TLVof 0.1 mg/m3 as
42 THORACIC NIOSH METHOD Metalworking Fluids NIOSH Method 5524, Issue 1 specifies a 2-umPTFE filter in a 37-mm filter cassette with an optional thoracic particulate sampler.At the time the method was published, the only thoracic sampler available commercially was a cyclone from BGI Incorporated.At this time, there is only one NIOSH method that specifies a thoracic particulate sampler.NIOSH Method 5524 for metalworking fluids specifies sample collection using a 2 um PTFE filter in a 37-mm cassette OR optional thoracic samplerAt the time the method was published, the only thoracic sampler available commercially was a cyclone from BGI Incorporated.
43 SKC THORACIC SAMPLERS Thoracic Parallel Particle Impactors (PPI) Designed to give a precise match to the thoracic criteriaUsed with any suitable 37-mm filter at 2 L/minSKC thoracic PPIs are not listed in the NIOSH method for metalworking fluids since the samplers were developed after the method was published.Since the method was published, SKC has developed a thoracic IMPACTOR. The SKC Parallel Particle Impactor or PPI wasdesigned to give a precise match to the thoracic criteria and can be used with any suitable 37-mm filter at 2 L/min.Note that the SKC thoracic PPI is not specifically listed in the NIOSH method for metalworking fluids since the samplers were developed AFTER the method was published.
44 SKC THORACIC PPIs REUSABLE SAMPLER Made of anodized aluminum DISPOSABLE SAMPLERMade of conductive plasticSKC Thoracic PPIs are available in reusable or disposable options.The REUSABLE thoracic PPI is constructed from anodized aluminum and the DISPOSABLE PPI is constructed from conductive plastic.The disposable model eliminates the burdens of sampler assembly and cleaning and is available pre-loaded with filters for designated applications.Both the reusable and the disposable thoracic PPI samplers are designed for use at 2 L/min with analysis following the same techniques as specified in government methods using traditional filter cassettes.SKCSKC
45 PPI SCHEMATIC Plate with four suitably sized inlet orifices Plate with disposable, pre-oiled porous plastic impaction substrates and outlet orificesMain collection filter (37mm) and filter support pad or screenHere you can see a schematic of the PPI operation.The four inlets on the sampler are precisely sized so the particulate matter collected on the final filter is a very close match to the criteria.Outlet to pump2 LPM
46 COLLECTION EFFICIENCY CURVES OF THORACIC SAMPLERS Here you can see the data generated by the SKC Aerosol Physicist for current thoracic samplers.Both the SKC thoracic PPI and the BGI thoracic cyclone give a close match to the international thoracic criteria.
47 DEFINITIONS OF RESPIRABLE PARTICULATES Throughout the history of occupational air sampling, several definitions of “respirable” particulate matter have been adopted by various organizations around the world.All definitions describe respirable particulate as that “small enough to reach the gas-exchange region”.Differences involve the 50% (median) cut-point of respirable dust samplers.Next, let’s examine RESPIRABLE DUST.AS IS
48 DEFINITIONS OF RESPIRABLE DUST SAMPLERS The British Medical Research Council (BMRC) originally defined respirable dust samplers as having a 50% cut-point of 5 microns.In the US, OSHA/MSHA define respirable dust samplers as having a 50% cut-point of 3.5 microns. OSHA is trying to change/update this definition in their 2013 Notice of Proposed Rulemaking on silica.
49 A CONSENSUS DEFINITION ON RESPIRABLE DUST SAMPLERS In an attempt, to reach aglobal consensus on thedefinition of respirabledust in the workplace,a compromise definitionwas developed for respirabledust samplers specifying a50% cut-point of 4 microns.In an attempt to reach global consensus in the occupational hygiene community, a compromise definition for respirable dust samplers was developed in the 1990’s specifying a 50% cut-point of 4 microns.
50 SKC CYCLONES AND FLOWRATES FOR 50% CUT-POINT OF 4 UM SKC Aluminum Cycloneat 2.5 L/minSKC mmSKC mmSKC has several cyclones that meet the new global consensus definition of respirable dust samplers AT DESIGNATED FLOW RATES.The SKC aluminum cyclone achieves a 50 % cut point at 2.5 L/min.
51 SKC CYCLONES AND FLOWRATES FOR 50% CUT-POINT OF 4 UM SKC GS-3 Cycloneat 2.75 L/minSKC mmSKC mmThe GS-3 cyclone achieves a 50 % cut point of 4 um at 2.75 L/min.
52 SKC CYCLONES AND FLOWRATES FOR 50% CUT-POINT OF 4 UM SKC GS-1 Cycloneat 2.0 L/minSKC Plastic Cycloneat 2.2 L/min(From SKC Ltd. in UK)The single inlet GS-1 cyclone has a designated flowrate of 2 L/min for a 4 um cut-point.The SKC plastic cyclone manufactured by SKC Ltd. in the UK has a designated flowrate of 2.2 L/min for a 4 um median cut-point.For those that want to achieve the 3.5 um cut-point specified by OSHA or MSHA, alternative flowrates can be provided by SKC for designated SKC cyclones.SKCSKC
53 A NEW RESPIRABLE DUST SAMPLER FROM SKC SKC has developed a new impaction based sampler for respirable dust called the Parallel Particle Impactor or PPI.The PPI was designed to improve performance characteristics evidenced with older traditional cyclones.AS IS
54 SKC RESPIRABLE PPI: FUNCTIONALITY The disposable models of the PPI look and function very much like a traditional 37-mm cassette.But the inlet comes pre-loaded with size-selective impactor plates that scrub out non-respirable dust.PPI samplers are smaller than traditional cyclones and can fit under a welder’s helmet or other PPE.Read first TWO bullets.Note that you are NOT concerned about how much particulate is collected at each of the individual inlets, but only what is collected on the final filter.
55 SKC RESPIRABLE PPI: FLOWRATES Single-use, disposable PPI models are available for use at either 2, 4, or 8 L/min.This provides flexibility in pump option and sample duration for various airborne concentrations.A calibration adapter (SKC ) is also available for the disposable PPI.2 L/min:8 L/min:Single-use, disposable PPI models are available for use at 2,4, or 8 L/min to provide flexibility in pump options and sample duration with various workplace concentration levels.A handy calibration adapter is also available for the dispsosable PPI.4 L/min:
56 PPI SAMPLER PERFORMANCE COMPARED TO CRITERIA PPI performance is a precise match to the current collection efficiency curves. Respirable PPI samplers conform to ISO/CEN/ACGIH/and NIOSHcriteria. As such, they meet the requirements specified in the 2013 OSHA proposed rulemaking on respirable crystalline silica.
57 SUB-MICRON RESPIRABLE DUST: DIESEL PARTICULATE MATTER (DPM) In a coal mine, workers may be exposed to both respirable coal dust and respirable DPM.Sampler was developed by NIOSH to separate these two contaminants based on particle size.DPM is less than 1.0 um in sizeCoal dust is greater than 1.0 um.Finally, let’s discuss a sub-micron respirable dust---DPM or Diesel Particulate Matter.This contaminant is quite common in mining operations due to diesel powered equipment used underground.Specifically if we look at coal mines, workers may be exposed to DPM along with respirable coal dust. So a sampler was developed by NIOSH to separate these 2 types of respirable dust based on the simple principle of particle size.Diesel particulates are less than 1 um and coal dust is great than 1 micron.
58 SKC 225-317 DPM Cassette with cyclone Here you can see a schematic of the DPM filter cassette with the GS-1 cyclone. The GS-1 cyclone meets the requirements of U.S. MSHA regulations.Note, however, that the cyclone serves only as a pre-scrubber to ensure the filter’s impaction plate is not overloaded. Other cyclones can be used if they meet your agency requirements.SKC DPM Cassette with cyclone
59 DPM SAMPLER UTILIZES THREE STAGES CycloneRemoves non-respirable particles that may overload the filterImpactor inside the filter cassetteRemoves respirable particles greater than 1.0 um in diameterHeat-treated quartz filterCollects particles less than 1.0 um in diameter for analysis of total or elemental carbon by NIOSH Method 5040AS IS
60 PORTABLE INSTRUMENT FOR MONITORING DUST EXPOSURES We have just reviewed air SAMPLING of particulates followed by laboratory determinations of exposure levels.In many operations, however, occupational hygienists need to determine dust exposure levels on-site.For this purpose, SKC offers direct-reading dust monitors.SKC
61 HAZ-DUST IVReal-Time Dust Monitor based on light scattering (aerosol photometer)Displays TWA, STEL, MIN, and MAX levels in mg/m3Internal pump to collect sample with filter cassette simultaneouslyCan add IOM sampler or GS cyclone to inlet for size-selectionThe HazDust IV is an aerosol photometer which uses the principle of light scattering for exposure measurements.The LCD displays TWA, STEL, MIN, and MAX levels mg/m3.There is also an internal pump to collect a filter sample if needed. An IOM sampler for inhalable dust or a GS cyclone for respirable dust can be added to the inlet for size-selection.
62 NOTE ON CALIBRATION OF HAZ-DUST IV Calibration Standard (SKC ) is a metal adapter that causes a known value to appear on LCD.The instrument will have a “k” value assigned by the factory when it is new.The “k” value should not deviate more than 10% during subsequent checks.The HazDust IV is factory calibrated in an aerosol chamber, but a calibration standard is also available so users can do frequent cal checks.AS IS.
63 NOTE ON CALIBRATION OF HAZ-DUST IV Haz-Dust monitors are factory calibrated using Arizona Road Dust (ARD).For higher accuracy, users can collect concurrent samples using filter cassettes, compare lab results to LCD readings, and generate a “correction factor” for their particular dust under study.
64 THANK YOU FOR TAKING THE TIME TO COMPLETE THIS TRAINING MODULE! If you have further technical questions, SKC at