Some Issues with the Silica in Construction Regulations. Abstract

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1 Some Issues with the Silica in Construction Regulations 2019 Indiana Safety & Health Conference 2:45 3:45 p.m February 27, 2019 Andrew A. Tony Havics, CIH, PE ph2, LLC 2017, A Havics 1 Abstract Employers have struggled to understand and implement the revised new : silica in construction rules. In particular this occurs when tasks are not those listed in Table 1. The regulations aren t particularly clear, but a deeper look into the pre amble and other parallel regulations can help if you have time to read hundreds of pages and do a lo of research. A second issue is what to do with SDS data on silica content. One asks several questions: if the product has less than < 1% silica am I good?, or is the SDS even correct?, or is the SDS even representative of respirable crystalline silica dust exposure? A third issue is the selection of analysis method. This includes selection of the method for both air and bulk samples, which preparation processes are used, and what other products or dusts may interfere with the results. A fourth concern is the potential to exceed other exposure limits (respirable nuisance dust PEL or the Portland Cement TLV), even if the respirable crystalline silica is below the OSHA PEL. 2017, A Havics 2 1

Outline 1. What is Silica 2. What is Respirable Crystalline Silica (RCS) 3. Table 1 or not? 4. SDS Issues 5. Analysis Issues 6. Other Exposure Limits 2019, A Havics 3 1.

2 Outline 1. What is Silica 2. What is Respirable Crystalline Silica (RCS) 3. Table 1 or not? 4. SDS Issues 5. Analysis Issues 6. Other Exposure Limits 2019, A Havics 3 1. What is Silica Silicon dioxide, also known as silica, silicic acid or silicic acid anydride is an oxide of silicon with the chemical formula SiO 2, most commonly found in nature as quartz. (Wikipedia) Forms: Quartz Cristobalite Tridymite Amorphous, Silica Gel Amorphous, Glass Amorphous, Fumed Silica 2019, A Havics 4 2

sampling device designed to meet the characteristics for respirableparticle size selective samplers specified in the International Organization for

3 2. What is Respirable Crystalline Silica (RCS)? Respirable crystalline silica means quartz, cristobalite, and/or tridymite contained in airborne particles that are determined to be respirable by a sampling device designed to meet the characteristics for respirableparticle size selective samplers specified in the International Organization for Standardization (ISO) 7708:1995: Air Quality Particle Size Fraction Definitions for Health Related Sampling 2019, A Havics 5 Cyclone Types Respirable Samplers Lee, Silica Meas with Resp Samplers, Ann Occ Hyg, 60, 3, , 2016 Zefon 2019, A Havics 6 3

4 3. Table 1 or not? Specified exposure control methods. (1) For each employee engaged in a task identified on Table 1, the employer shall fully and properly implement the engineering controls, work practices, and respiratory protection specified for the task on Table 1, unless the employer assesses and limits the exposure of the employee to respirable crystalline silica in accordance with paragraph (d) of this section. 2019, A Havics 7 (d) Alternative exposure control methods. For tasks not listed in Table 1, or not fully and properly implement the engineering controls, work practices, and respiratory protection in Table , A Havics 8 4

5 Exposure Assessment Each employee Is or is reasonably expected to be exposed to RCS at or above 25 ug/m 3 Option 1: performance option (d)(2)(ii) Option 2: scheduled monitoring (d)(2)(iii) 2019, A Havics 9 Option 1: performance option (d)(2)(ii) 8 hour TWA exposure each employee Any combination of air monitoring data or objective data Ref , 2004 USG, OSHA 29 CFR 1926 Respirable Silica Dust Exposure, Objective Test Data, USG Sheetrock Brand Dust Control Joint Compound, , A Havics 10 5

6 Option 2: scheduled monitoring (d)(2)(iii) Initial monitoring of 8 hour TWA Each employee 1+ Samples Reflect the exposures of employees on each shift each job classification in each work area 2019, A Havics 11 Exposure Assessment (alternative) Follow Table 1? No Yes Administrative Controls Engineering Controls PPE & RP each employee air monitoring data + objective data each employee air monitoring data Performance Based Assessment each employee objective data Scheduled Monitoring 1+ Samples for: each shift each job classification in each work area Evaluation of Results 2019, A Havics 12 6

7 Objective data information, such as air monitoring data from industry wide surveys or calculations based on the composition of a substance, demonstrating employee exposure to respirable crystalline silica associated with a particular product or material or a specific process, task, or activity. The data must reflect workplace conditions closely resembling or with a higher exposure potential than the processes, types of material, control methods, work practices, and environmental conditions in the employer s current operations. 2019, A Havics 13 Comments 1 Study of a few samples is NOT an industry Wide Study Each particular product or material or a specific process, task, or activity means the data need to show that each task or product are evaluated under varying settings (conditions) Data are needed for each set of similar conditions at a site for all aspects: processes, types of material, control methods, work practices, and environmental conditions 2019, A Havics 14 7

8 Comments Example 1: Data outdoors is not the same as indoors Example 2: Data while it is raining is not the same as when it is dry Example 3: Working with a wet material is not the same as working with a dry material. Example 4: 1% silica in a bulk material is not the same as 90% silica 2019, A Havics 15 Example 1. Drywall Installation Sample Classification Respirable Crystalline Silica Concentration (ug/m3) 8-Hr TWA HPS-001 Finisher HPS-002 Finisher 6.67 HPS-006 Finisher HPS-007 Finisher 21.7 HPS-011 Finisher HPS-012 Finisher HPS-003 Cleaner < 8.37 HPS-008 Cleaner HPS-013 Cleaner HPS-004 Cutter 4.99 HPS-009 Cutter 5.14 HPS-014 Cutter Mean UCL95% , A Havics 16 8

9 Example A Product < 1.43 % Respirable Respirable 1 10% Silica Product Respirable 40 70% Silica Product 2019, A Havics 17 Example 2. Concrete Dowell Drilling NOT following Table 1 Sample Classification Respirable Crystalline Silica Concentration (ug/m3) 8-Hr TWA FCU-04 PBZ, Drilling 36.2 Mean UCL 95% FCU-13 PBZ, Drilling FCU-20 PBZ, Drilling 24.8 FCU-15 Area, Drilling < 4.04 FCU-22 Area, Drilling FCU-06 Area, Drilling , A Havics 18 9

10 Example 3. General Cleanup Sample Classification Respirable Crystalline Silica Concentration (ug/m3) 8-Hr TWA FCU-01 PBZ, Cleanup 27.0 Mean UCL 95% FCU-09 PBZ, Cleanup ,582 FCU-18 PBZ, Cleanup 2, , A Havics 19 Suggestion 6 7 Full Shift 8 Hr TWA per Similar Exposure Group (SEG) [i.e., drillers, mixers, etc.] Comparable conditions (outdoor, RH, water usage) Same Type of Product & Process Calculate UCL 95% 1. ASTM, ASTM D , Standard Practice for Asbestos Exposure Assess for Repetitive Maintenance and Installation Tasks, Mulhausen, J.R and J. Damiano: A Strategy for Assessing and Managing Occupational Exposures, 2 nd ed.. AIHA, Fairfax, VA. 349 pp Ignacio, Joselito, and William Bullock: A Strategy for Assessing and Managing Occupational Exposures, 3rd edition. AIHA, Fairfax, VA OSHA, CPL , Inspection Procedures for Occupational Exposure to Asbestos Final Rule 29 CFR Parts , , and , OSHA, CPL , Lead in Construction, OSHA, FR 81, 58, Occupational Exposure to Respirable Crystalline Silica, Final Rule, , , A Havics 20 10

11 2019, A Havics 21 Objective Data but is it applicable? Small semi auto machine (controlled) the exposures were < ug/m 3 RCS [Cooper] 410 to 890 ug/m 3 of RCS depending on Bit [Carty, et al.] 97 air samples of drilling concrete and calculated a geometric mean of 200 ug/m 3 RCS [Flannagan] Highway construction 50 1,490 ug/m 3 RCS [Blute] < ug/m 3 RCS during general drilling of concrete [Chisholm] ug/m 3 RCS during dry drilling with limited ventilation [Chisholm] GM of 308 ug/m 3 for RCS with uncontrolled drilling [Shepard] concrete wall dry drilling with pneumatic and electric drills and found ug/m 3 [Lofgren] 2019, A Havics 22 11

12 4. SDS Issues IARC Crystalline silica as quartz or cristobalite NTP Silica, Crystalline (Respirable Size) Per HCS, any mixture shall be assumed to present a carcinogenic hazard if it contains a component in concentrations of 0.1 percent or greater which is considered to be a carcinogen by IARC, NTP or OSHA OSHA, 1986: Information regarding the evidence of carcinogenicity must be included on required labels and material safety data sheets for crystalline silica, and for products containing crystalline silica, where employee exposure to the crystalline silica may occur. OSHA, 1991: For all practical purposes, therefore, the requirements of the HCS to provide an appropriate warning label, apply to products containing greater than 0.1 percent crystalline silica or total quartz by weight or volume, as determined by analysis of a bulk sample of the original product. 2019, A Havics 23 Quartz SDS Terms ID Material SDS Listing Equivalent 1 Concrete Mix Natural Sand Crystalline Quartz 2 Concrete Mix Class F Fly Ash Amorphous Silica and Crystalline Silica (Ex. 52% by analysis) et al. 3 Cement Mix Silicon Dioxide (SiO 2 ) Crystalline Quartz 4 Mortar Mix Sand, Silica, Quartz Crystalline Quartz 5 Mortar Mix Ground Granulated Blast Furnace Slag Should be a lot of Amorphous Silica 6 Fireproofing Quartz (SiO2) < 2% Crystalline Quartz 7 PC Type 1 Respirable quartz (CAS# ) greater than 0.1% by weight 8 Roofing Tile Quartz (SiO2) 60 85% Cristobalite < 2.5% 9 Lightweight Crystalline Silica Insulating Concrete Crystalline Quartz Crystalline Quartz Crystalline Cristobalite Crystalline Quartz 2019, A Havics 24 12

13 SDS Terms ID Material SDS Listing Equivalent 10 Polyurethane MICROCRYSTALLINE SILICA Crystalline Quartz Coating 11 Fireproofing Crystalline Silica Crystalline Quartz 12 PC Silica Crystalline Quartz 13 Concrete Mix Silica Fume Portland and/or Slag Cement Quartz (crystalline silica) 14 Concrete and Cement Mixes Sand, Silica, Quartz ( %) Portland Cement (10 30%) Fly Ash (5 10%) Non Regulated Silica??? Crystalline Quartz Crystalline Quartz?????? 15 Fly Ash ASTM C Quartz (1 17%) Crystalline Quartz 16 Fly Ash Class C Crystalline Silica (< 10%) Crystalline Quartz 2019, A Havics 25 SDS v Bulk Analysis Sample Material SDS Crystalline Quartz (%) by FTIR HPD-001 HPD-002 HPD-003 Drywall & Joint Compound (from installed product) AG 1-5 GP NG* USG* Crystalline Quartz (%) by XRD BH-B-01 BH-B-05 Mortar % (n =6) FCU-B-01 Fireproofing < Crystalline Quartz by PLM (%) FCU-B-02 Cement Type N FCU-B-03 Cement Type S < 0.33 FCU-B-04 Cement Type I & II < 0.33 FCU-B-06 Fireproofing < 2 < 0.33 FCU-B-07 Cement Type N < 0.33 FCU-B-08 Cement Type S < 0.33 FCU-B-09 Cement Type I & II < , A Havics 26 13

14 Am I OK if the Bulk Value is < 1%? Sample Material SDS Crystalline Quartz (%) by FTIR Crystalline Quartz (%) by XRD FCU-B-01 Fireproofing < FCU-B-06 Fireproofing < 2 < , A Havics 27 Example 4. Insulation Installation Sample Classification Respirable Crystalline Silica Concentration (ug/m3) 8-Hr TWA Mean UCL 95% FCU-02 FCU-10 FCU-19 PBZ, Fireproof Mixing PBZ, Fireproof Mixing PBZ, Fireproof Mixing , A Havics 28 14

15 Something to Consider % Silica in Respirable Dust Respirable Crystalline Silica Concentration (ug/m3) 8-Hr TWA Respirable Nuisance Dust (mg/m 3 ) , A Havics Analysis Issues FTIR 2019, A Havics 30 15

FTIR for Silica 670 820 2019, A Havics 31 FTIR Silica Interferences Mineral Major Interfering Peak (cm -1 ) Quartz 780, 800 Cristobalite 798 Tridymite 789 Albite** 746, 788 Amorphous

16 FTIR for Silica , A Havics 31 FTIR Silica Interferences Mineral Major Interfering Peak (cm -1 ) Quartz 780, 800 Cristobalite 798 Tridymite 789 Albite** 746, 788 Amorphous (non-crystalline) 800 Silica Anorthite** 730, 760 Kaolinite* 754, 795 Montmorillonite 797 Muscovite** 750, 800 Mullite* 748, 837 Orthoclase** 730, 745, 765 Pyrophyllite 814, 830 Talc 778, 797 Vermiculite 755, 810 * Used in ceramics industry ** Common constituent in granites Clay mineral 2019, A Havics 32 16

$X ray Diffraction (XRD) The angle between the beam axis and the ring is called the scattering angle and in X- ray crystallography always denoted as 2θ (in scattering of visible light the convention$ 1400 1300 1200 1100 1000 900 No Substantial: 800 700 600 500 400 300 Cement [C2S (belite & felite), 200 C3S (alite), Ca4Fe4O10 to Ca4FeAl3O10, ferrite] Expanding clays Feldspar 100 0 2 10 20 30

1400 1300 1200 1100 1000 900 No Substantial: 800 700 600 500 400 300 Cement [C2S (belite & felite), 200 C3S (alite), Ca4Fe4O10 to Ca4FeAl3O10, ferrite] Expanding clays Feldspar 100 0 2 10 20 30

17 X ray Diffraction (XRD) The angle between the beam axis and the ring is called the scattering angle and in X- ray crystallography always denoted as 2θ (in scattering of visible light the convention is usually to call it θ) 2019, A Havics 33 X ray Diffraction XRD Found: Terrazzo Flooring Quartz Calcite Dolomite Muscovite Clinochlore Lin (Counts) No Substantial: Cement [C2S (belite & felite), 200 C3S (alite), Ca4Fe4O10 to Ca4FeAl3O10, ferrite] Expanding clays Feldspar Theta - Scale Terazzo Flooring - Affected - File: TH-1c.raw - Type: Locked Coupled - Start: End: (C) - Quartz - SiO2 - Y: % - d x by: 1. - WL: I/Ic PDF S-Q 25. Operations: X Offset Import Terazzo Flooring - Control - File: TH-2c.raw - Type: Locked Coupled - Start: End: S Operations: Y Scale Add 220 X Offset Import (C) - Calcite - Ca(CO3) - Y: % - d x by: 1. - WL: I/Ic PDF S (C) - Dolomite - from Eocene, Jamaica - CaMg(CO3)2 - Y: 8.62 % - d x by: 1. - WL: (C) - Muscovite - from Panasqueira, Portugal - KAl3Si3O10(OH)2 - Y: 1.90 % - d x b (C) - Clinochlore - (Mg4.715Al.694Fe.269Fe.109Cr.128Ni.011)(Si3.056Al Y: , A Havics 34 17

18 Mortar Mix 60.1% crystalline silica < 5% Calcite < 5% Hatrurite (C3S, Alite) 2019, A Havics 35 XRD Silica Interferences Interfering Phase Quartz (100) 2θ = Quartz (101) 2θ = Quartz (112) 2θ = 50.15, Quartz (211) 2θ = 59.94, Albite** Anatase (Titanium Dioxide white pigment) Anorthite** Aragonite (Calcium carbonate) Biotite** Calcium Silicate Hydrate (C-S-H) Graphite Gypsum (drywall) Kaolinite* Kyanite* Maghemite Microcline** Mullite* Muscovite** Ordinary Portland Cement (OPC) Sillimanite Vaterite (Calcium carbonate) Wollastonite Wustite Zircon Portlandite (slaked lime) * Used in ceramics industry Cons tuent in Limestone ** Common constituent in granites Cement Concrete related product Trace in granite 2019, A Havics Clay mineral 36 18

19 , A Havics 37 Issues: FTIR vs. XRD Sample Material Quartz (%) [Crystalline Silica] by FTIR Quartz (%) [Crystalline Silica] by XRD Calcite (CaCO3) by XRD Anhydrite Hatrurite/ Alite/C3S by XRD BH-B-01 (5) Mortar Mix, Ground < 5% < 5% FCU-B-01 Fireproofing < < 5% > 20% FCU-B-02 FCU-B-05 FCU-B-10 Cement Type N Concrete Dust from Grinding Concrete Dust from Grinding < > 20% 5-20% % ND > 20% ND 2019, A Havics 38 19

XRD Preparation Muffle Furnace V Plasma Etch 2019, A Havics 39 6.

OSHA PEL 5 mg/m 3 ACGIH TLV 3 mg/m 3 OPC NIOSH REL 5 mg/m 3

20 XRD Preparation Muffle Furnace V Plasma Etch 2019, A Havics Other Exposure Limits Other Exposure Limits RND/Respirable PNOC OSHA PEL 5 mg/m 3 ACGIH TLV 3 mg/m 3 OPC NIOSH REL 5 mg/m 3 Respirable ACGIH TLV 1 mg/m 3 Respirable OSHA RND 5 mg/m , A Havics 40 20

Example 5. Drywall Installation Sample Classification Respirable Nuisance Dust Concentration (mg/m3) 8-Hr TWA HPS-001 Finisher 0.79 HPS-002 Finisher 0.79 HPS-006 Finisher 2.13 HPS-007 Finisher 1.

21 Example 5. Drywall Installation Sample Classification Respirable Nuisance Dust Concentration (mg/m3) 8-Hr TWA HPS-001 Finisher 0.79 HPS-002 Finisher 0.79 HPS-006 Finisher 2.13 HPS-007 Finisher 1.1 HPS-011 Finisher 3.78 HPS-012 Finisher 1.51 HPS-003 Cleaner 1.29 HPS-008 Cleaner 1.99 HPS-013 Cleaner 2.05 HPS-004 Cutter 2.75 HPS-009 Cutter 5.36 HPS-014 Cutter 4.51 Mean TLV = 3 mg/m 3 PEL = 5 mg/m 3 UCL95% /11 over PEL 3/11 over TLV 2019, A Havics 41 Objective Data USG, OSHA 29 CFR 1926 Respirable Silica Dust Exposure, Objective Test Data, USG Sheetrock Brand Dust Control Joint Compound, 2017 Note: RND PEL = 5 mg/m 3 TND PEL = 15 mg/m , A Havics 42 21

22 Example 6. General Cleanup Sample Classification Respirable Nuisance Dust Concentration (mg/m3) 8-Hr TWA FCU-01 PBZ, Cleanup < 0.1 Mean UCL 95% FCU-09 PBZ, Cleanup FCU-18 PBZ, Cleanup , A Havics 43 Example B: Concrete & Cleaning 2019, A Havics 44 22

23 Questions? Andrew Anthony Tony Havics, PE ph2, LLC 5250 E US Highway 36, Suite 830 Avon, IN (317) Office aahavics@ph2llc.com 2019, A Havics 45 23

RESPIRABLE CRYSTALLINE SILICA

RESPIRABLE CRYSTALLINE SILICA Presented by: Michael Martin, Industrial Hygiene Consultant Arizona Division of Occupational Safety and Health This presentation contains a summary of OSHA requirements found