TITLE:	ES&H Manual
DOCUMENT ID:	6683 Appendix T1 Silica Work Requirements

Jefferson Lab has determined that working with silica carries an unmitigated Risk Code ≥2. At a minimum all tasks involving silica are discussed with the supervisor prior to commencement. An Operational Safety Procedure (OSP) is written for any work considered to be Risk Code >2 in accordance with ES&H Manual Chapter 3210 Work Planning, Control, and Authorization Process.

1.0 Purpose

This appendix provides Jefferson Lab’s minimum requirements when working with silica, including work planning, work activities, and clean-up.

2.0 Scope

This procedure defines mitigation measures for activities involving silica over and above those required by standard protecting measures to reduce respirable silica below occupational exposure limits.

Operations, not listed below, that cause silica particles to become airborne are considered to have a Risk Code >2 and require a Work Control Document. These activities include dry sweeping, scraping, or using compressed air. Contact Industrial Hygiene for appropriate mitigation requirements for these activities.

Depending on the complexity of the activity (i.e. indoors, confined space), Industrial Hygiene may require "hold points" to verify control adequacy (e.g. engineered, Personal Protective Equipment (PPE)). Involve Jefferson Lab Industrial Hygiene in work planning activities. 

The process steps for this procedure coordinate with ES&H Manual Chapter 6683 Silica Safety Program.

3.0 Responsibilities

NOTE: Management authority may be delegated to a task qualified Jefferson Lab employee at the discretion of the responsible manager.

3.1 Trained Worker

· Complete and maintain appropriate training:

o SAF138 Silica Dust Hazards

o Medical monitoring, as required

· Perform work activities within hazard controls.

· If work conditions change or the mitigations do not appear to be effective (i.e. visible dust), request a hazard evaluation of work activities from Industrial Hygiene

3.2 Supervisor/Technical Representative (TR)/Sponsor:

· Provide a complete Work Plan in accordance with process steps.

· Assign only Trained Workers to silica work.

3.2.1 TR also:

· Inform subcontractors that their Activity Hazard Analysis (AHA or THA) must include the planned technique(s) to mitigate silica exposure and the program used to train workers.

o Program must comply with 29 CFR 1910 or 1926 requirements as applicable to the task being performed.

· If provided, submit subcontractor’s silica AHA to Jefferson Lab’s Silica Subject Matter Expert (see ES&H Manual Chapter 2410 Appendix T1 Hazard Issues List – Silica) for approval prior to commencement of work.

3.3 Industrial Hygiene

· Perform silica work/area hazard evaluation as appropriate.

· Provide HEPA vacuums as requested.

4.0 Process Steps

The following tables provide examples of typical activities and materials associated with work at Jefferson Lab. Controls for the activities below are expected to reduce potential exposure below the OSHA action limit and 2016 ACGIH TLV for silica.

The list was developed using objective data and/or previous sampling data; it is not all-inclusive. Evaluate all tasks prior to commencement of work for potential silica generation.

If your task is not on this list, contact IH.

Typical JLab Silica Work*	Duration / Scope per 8-hour shift	General Location	Required Controls**	Notes
Grout/Mortar/Cement Mixing	≤5 sq. ft. / ≤7 bags	Indoors/Outdoors	B, D	Keep employees upwind of dust when outdoors. Wet bags with water prior to opening, continue to mist when mixing until thoroughly wetted (no visible dust)
Grout/Mortar Mixing	˃5 sq. ft. / >7 bags	Indoors/Outdoors	A, C, D	Where feasible, order and use pre-mixed grout, concrete, or mortar to eliminate silica hazard. Wet bags with water prior to opening, continue to mist when mixing until thoroughly wetted (no visible dust)
Shoveling Sand	Any	Outside	B	Keep employee upwind of dust when outdoors
Handheld and stand-mounted drills	< 4 holes	Outdoors	B	Use HEPA vacuum or wet-methods for housekeeping (no dry sweeping)
	< 4 holes	Indoors	A* or B	* use HEPA vacuum at the point of operation when drilling overhead
	>= 4 holes	Indoors/Outdoors	A
Saw Cutting – Chop Saw/Stationary Saw	< 4 hours	Outdoors	B, D	Saw must be equipped with integrated water delivery system that continuously feeds water to the blade. (misting with hand water sprayer is not adequate)
	> 4 hours	Outdoors	B, C, D
Saw Cutting – Handheld power saw	<1 linear ft.	Outdoors	B, D
	>1 linear ft.	Outdoors	B,C, D
Saw Cutting – Walk Behind Saw	< 4 hours	Outdoors	B, D
	> 4 hours	Outdoors	B, C, D
	< 1 hour	Indoors	B, D
	> 1 hour	Indoors	B, C, D
	> 4 hours	Indoors	B, C, D	Increase respiratory protection to full-face respirator or Powered Air Purifying Respirator
Floor Surface Grinder	< 4 hours	Indoors/Outdoors	A or B, C, D
	> 4 hours	Indoors	A, C, D	Increase respiratory protection to full-face respirator or Powered Air Purifying Respirator
	> 4 hours	Outdoors	A or B, C, D	Increase respiratory protection to full-face respirator or Powered Air Purifying Respirator
Drywall/Sheetrock sizing (score & snap, hand saw, rotary cutter)	Any	Indoors/Outdoors		Use HEPA vacuum for housekeeping (no dry sweeping)
Joint Compound Sanding	>1 linear ft.	Indoors/Outdoors	A, C, D	Low dust joint compounds are available (e.g. USG Sheetrock Brand Dust Control Joint Compound)
Tuck Pointing/Grout Repair - Hand tools	Any	Indoors/Outdoors	B, D	Water must be combined with a surfactant.
Tuck Pointing/Grout Repair - Power Tools	Any	Indoors/Outdoors	A, B, C, D	Water must be combined with a surfactant. Full-face respirator required. Indoors tuckpointing requires enclosure with negative air machine to limit exposure to other workers.
Jack Hammering	< 2 hours	Outdoors	B, D	Misting with hand water sprayer is not adequate. Use water from building supply/hose to provide adequate water flow directly to chipping point.
	> 2 hours	Outdoors	B, C, D
	Any	Indoors	A, B, C, D	Enclosure with HEPA filtered negative air machine to limit exposure to co-located workers. Increase respiratory protection to full-face respirator or Powered Air Purifying Respirator when duration exceeds 2 hours.
Change HEPA vacuum collection bag/empty dust collection canister	Any	Indoors/Outdoors	A or C, D
Heavy equipment and utility vehicles; used during demolition activities (e.g. hoe-ramming)	<4 hours	Outdoors	B, C	Sprayer must wear respirator
	>4 hours	Outdoors	B, C	Sprayer and operator must wear respirator

*Task listed are typical for JLab maintenance and operations. JLab Industrial Hygiene Group must evaluate tasks not included in this table.

**Controls - NOTE: OTHER PPE WILL BE REQUIRED FOR ADDITIONAL HAZARDS

A = Local exhaust ventilation or Point of Operation exhaust with HEPA filter & minimum flow rate of 25 cfm

B = Water

C = Half-face respirator with N100 or equivalent filtration

D = First aid flush of eye contamination

Guidance by Jefferson Lab Industrial Hygiene, March 2021

4.1 Work Planning

The following process steps are completed by the Supervisor.

Step 1: Task Hazard Analysis (THA) (see ES&H Manual Chapter 3210 Appendix T2 Task Hazard Analysis Worksheet) include:

· Engineering Controls – Such as water applied at point of generation, local exhaust ventilation with HEPA filtration. Contact Industrial Hygiene for other approved methods.

· Training Requirements – SAF138 Silica Dust Hazards and medical monitoring.

· Personal Protective Equipment (PPE) – Air Purifying Respirators or equivalent (see ES&H Manual Chapter 6630 Appendix T2 Respirator Use and Approval Requirements)

Step 2: Request a hazard evaluation from Industrial Hygiene to address additional concerns.

Step 3: Assign only Trained Workers to the work. Ensure they are appropriately trained, understand the hazards, and implement appropriate hazard mitigation(s) prior to work.

Step 4: If area where the task is performed will or could potentially exceed the OSHA action limit/TLV the area must be posted as a regulated area with the sign show in Figure 1:

Figure 1: required posting for regulated areas

4.2 Work Activities

Only Trained Workers may perform the following process steps.

Step 1: Abide by the work plan

· Follow all safety precautions as outlined within the work plan.

· If work conditions change or the mitigations do not appear to be effective (i.e. visible dust), request a hazard evaluation of work activities from Industrial Hygiene.

4.3 Clean-up

NEVER dry sweep, dry brush, or use compressed air to clean-up.

Step 1: Vacuum

· Use a HEPA vacuum –obtain from Industrial Hygiene for non-radiological areas, contact Radiation Control for radiological areas.

· Clean the exterior surface of the vacuum prior to returning to owner.

· Do not empty the vacuum bag or remove the HEPA filter. Contact HEPA vacuum owner (IH or Radcon)

NOTE: Only Radiation Control Department HEPA Vacuums with current performance testing validations are authorized for use within areas containing radioactive material (e.g.: experimental halls and beam enclosures). All HEPA vacuums and the components, used within these areas, must be surveyed prior to removal and may NOT be disposed of in ordinary trash.

HEPA vacuums used for silica in non-radioactive material areas need to be coordinated through Industrial Hygiene

All Jefferson Lab HEPA vacuums are required to be inspected annually. See Industrial Hygiene for more information regarding these types of inspections.

Step 2: Surface Wipe Down

· Use wet cloths or rags to wipe up residual material.

· Immediately dispose of used cloths or rags in ordinary trash.

References:

· Bello, A., Mugford, C., et al, Characterization of Occupational Exposures to Respirable Silica and Dust in Demolition, Crushing, and Chipping Activities. Annals of Work Exposures and Health, 2019, Vol. 63, No. 1, 34–44.

· BNL, ESH Guide: Inhalation & Dermal Hazards, Silica Control Measures. 07/12/18

· National Gypsum Company, Dust Emission Study: Sizing of National Gypsump 5/8” fire-shield Type X Drywall. April 2015.

· Alberta Human Services, Evaluation of Worker Exposure to Crystalline Silica in the Alberta Construction Industry. March 26, 2012

· OSHA, Controlling Silica Exposures in Construction. OSHA 3362-05, 2009

· USG Sheetrock Brand Dust Control joint compound https://www.usg.com/content/usgcom/en/campaigns/dust-control.html

5.0 Revision Summary

Revision 1.2 – 03/22/21 – Periodic Review; Updated header and footer, updated process steps to match lab operations, updated SOTR to TR, updated the references. No new approval needed, minor edits.

Revision 1.1 – 04/24/18 – Removed outdated TLV reference per CATS#STR-2017-12-01-03

Revision 1.0 – 02/24/17 – Updated TPOC from D.Owen to J.Williams; updated to comply with new OSHA standard re: CATS Issue #PD-2016-01-01

Revision 0.3 – 01/07/16 – Updated Scope to include Industrial Hygiene for guidance in work planning activities

Revision 0.2 – 03/17/15 – Periodic Review; replaced Silica Table under 4.0 Process Steps per Technical POC

Revision 0.1 – 06/28/13 – Added responsibility to request hazard evaluation of work to 3.1 Trained Worker and added conditional step to 4.2 Work Activities per M.Logue

Revision 0.0 – 06/08/12 – Initial content

ISSUING AUTHORITY	TECHNICAL POINT-OF-CONTACT	APPROVAL DATE	REVIEW DATE	REV.
ES&H Division	Jennifer Williams	04/24/18	03/22/24	1.2

This document is controlled as an on-line file. It may be printed but the print copy is not a controlled document. It is the user’s responsibility to ensure that the document is the same revision as the current on line file. This copy was printed on 3/22/2021.