Crystalline Silica. Health Effects & The Proposed Standard

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1 Crystalline Silica Health Effects & The Proposed Standard Lee McKinney, CIH Compliance Safety & Health Officer NCDOL/OSH Division - Charlotte Field Office (704)

2 Do you clean teeth in Factories?

3 Industrial Hygiene Methods &Practices Anticipation Recognize Hazards Evaluate Recommend Controls Confirm

4 Occupational Lung Diseases Particle deposition Aerodynamic diameter >10 µm deposited in nasal mucosa Particles between 3 and 10 µm deposited throughout tracheobronchial tree Particles 0.1 to 3 µm are deposited in and around the alveoli.

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6 What Is Crystalline Silica? Naturally occurring mineral compound 3 mineralogical forms Quartz most common Cristobalite Tridymite

7 Health Effects Silicosis (pulmonary fibrosis) Chronic, accelerated, acute A continuing problem Hawks Nest Tunnel Disaster 476 deaths from acute silicosis

8 Silicosis still an issue 200 deaths due to silicosis in U.S. every year Underlying cause of death of 868 M and 46 W in non-mining ,000 U.S. fatalities since

9 Other Health Effects Lung cancer Tuberculosis Chronic obstructive pulmonary disorder 9

10 Symptoms - Chronic Silicosis There may be no symptoms in the early stages. As the disease progresses Cough Breathlessness Weakness

11 Proposed Standard for Crystalline Silica 11

12 "In the absence of effective specific treatment for silica-related diseases, the only approach remains primary prevention, i.e., control of exposure to respirable silica." -Official Statement of the American Thoracic Society on the Adverse Effects of Crystalline Silica Exposure

13 OSHA's current (PELs) for crystalline silica were adopted in 1971 and have not been updated since that time. Time to move forward?

14 OSHA s Proposed Rule Two proposed standards: One for General Industry One for Construction Same PEL for both: 50 µg/m 3

15 Health Benefits of Rule Nearly 700 fatalities avoided annually Lung cancer: 165 Silicosis/non-cancer lung diseases: 381 End-stage kidney disease: 153 Over 1,600 silicosis cases avoided Annually

16 NIOSH Recommendations

17 Reasons for Proposal Current Permissible Exposure Limits (PELs) are formulas that many find hard to understand Quartz-containing respirable dust: 10 mg/m3 % respirable quartz

18 Some International Silica OELs Canada Alberta 25 µg/m3 Nova Scotia 25 µg/m3 Saskatchewan 50 µg/m3 Italy 25 µg/m3 Ireland 50 µg/m3 Netherlands 75 µg/m3

19 OSHA s Proposed Rule Includes provisions for: Measuring worker exposures to silica; Limiting access to areas where workers could be exposed above the PEL;

20 Cont. Use of dust controls; Use of respirators when necessary; Medical exams for highly exposed workers; Worker training and Recordkeeping. 20

21 Flexibility for Dust Controls Employers can use any dust or work practice controls to protect workers, such as: Water sprays Enclosures Vacuum dust collection systems Prohibiting dry sweeping

22 Dust Controls Grinding without dust controls Grinder with vacuum dust collector

23 Use of Respirators Allows for respirator use when Dust or work practice controls cannot reduce exposures to the PEL Dust controls are being installed

24 OSHA Listens to Small Business Concerns Small businesses asked OSHA to simplify compliance, while maintaining worker protection. Helps me too..

25 OSHA Listens to Small Business Concerns OSHA proposes Table 1 which reduces employer burdens of having to determine: Employee exposures What types of controls are needed

26 Table 1 Example Table 1. Exposure Control Methods for Selected Construction Operations Operation Using Stationary Masonry Saws Engineering and Work Practice Control Methods Use saw equipped with integrated water delivery system. (Plus additional specifications) Required Air- Purifying Respirator (Minimum Assigned Protection Factor) 4 hr/day None > 4 hr/day Half- Mask (10)

27 Small Business Input Both fixed and performance option for exposure determination Initial medical surveillance can be offered within 30 days instead of pre-placement.

28 Cont.. Specific methods for laboratory analysis included Table 1 limits respirator use for tasks performed <4 hours/day

29 Crystalline Silica Exposures

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35 Workplace Exposures Solid dust particles generated from silicacontaining materials by Handling Grinding Blasting Drilling Crushing

36 Workplace Exposures High historical exposures: Sandblasting Tunneling Granite cutting/finishing Cement Working with Natural Minerals

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40 OSHA PEL A moving target based on % SiO 2 More silica in the product the lower the PEL Significant mathematical difference between 1910 and

41 OSHA PEL for General Industry Quartz-containing respirable dust: 10 mg/m3 % respirable quartz + 2 Cristobalite and Tridymite: use ½ of the value calculated from the formula for quartz

42 This equation produces a range of PELs for different quartz levels PEL = 0.1 mg/m 3 for pure (100%) quartz PEL = 5.0 mg/m 3 for 0% quartz The same as respirable nuisance dust

43 OSHA PEL for Construction millions of particles per cubic foot (mppcf) Quartz (respirable dust): 250 mppcf % silica + 5 OSHA-adopted conversion factor: 1 mppcf = 0.1 mg/m3 respirable dust

44 PEL Comparison For a sample with 50% quartz: General Industry: 10 / [50 + 2] = mg/m 3 = 192 µg/m 3 Construction: 250 / [50 + 5] = 4.55 mppcf 4.55 mppcf = mg/m 3 = 455 µg/m 3 44

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46 Results Over exposed for general industry 8-hr exposure = 3.05 mg/m3 PEL = 2.57 mg/m3 Not overexposed for Construction 8-hr exposure = 30.5 mppcf PEL = mppcf 46

47 Sampling in the last 6 months Exposure Group Time Sampled in minutes % SiO2 based on MSDS Calculated PEL in mg/m 3 Results in mg/m 3 Proposed PEL in mg/m 3 Sandblaster sand HP Cleaner Sand* wet brick cutting Gypsum Mixer Sandblaster Staurolite 449 >70% , >70% ? , <2% 2,572 3, <3% ,

48 Sampling in the last 6 months Exposure Group Time Sampled in minutes Calculated PEL in mppcf Results in mppcf Mppcf to mg/m 3 Proposed PEL in mg/m 3 wet brick cutting Gypsum Mixer Construction calculations

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50 Crystalline Silica PELs: Whether you work in General Industry or in Construction: The more crystalline silica there is in the dust, the less of the dust you should breath

51 Silica How can I learn more about the proposed rule? Visit OSHA s Silica Rulemaking webpage at 51

52 Questions Paul Sullivan, OSH Division/Compliance Charlotte Field Office OSH Division/Education, Training & Technical Assistance

53 Lee M. McKinney, CIH OSH Division/Compliance Charlotte Field Office

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55 The Quick look is it lead?

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59 Asbestos Country Mine Production Reserves United States N/A N/A Small Brazil 307, ,000 11,000,000 China Kazakhstan Russia Other Countries 420, , , ,000 1,000,000 1,000, Large Large Large Moderate

60 Domestic Production and Use Asbestos consumption in the United States was estimated to be 950 tons imports The chloralkali industry accounted for an estimated 67% U.S. consumption; roofing products, 30%; and unknown applications, 3%.

61 unknown applications, 3%. 3% of 950 tons? ~60,000 lbs of asbestos used in industry Where is 3%