eLCOSH : Guides for Managing Silica Control Programs in Construction

Guides for Managing Silica Control Programs in Construction

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Mark Goldberg, Nancy Clark, Katya Wanzer, Norman Zuckerman

Mount Sinai School of Medicine, Hunter College - Urban Public Health Program

Overview

Project Timetable
Section 1: Planning

Who is Responsible for Planning
What Plans Need to be Made
When to Plan

Section 2: Writing a Site Specific Compliance Program
Section 3: Implementing

Managing the Control Plan
Making the Control Plan Work

Section 4: Evaluating
Section 5: Silica Controls Selection Chart
Section 6: Checklists

Note to the User:

Engineering and work practice controls for lead dust are widely available and in common use. This is not the case for crystalline silica. We recommend that contractors engaging in silica dust generating tasks:

1. Develop a site-specific silica compliance program for managing engineering and work practice controls.

2. Use engineering and work practice controls for silica-generating tasks, even though they might not always be readily available. Water and a spray can, of course, are not hard to find. Suggestions are provided on where to look for controls. As is often the case in construction, a little creativity can go a long way.

Overview

Why institute an engineering and work practice control program?

The OSHA Special Emphasis Program (SEP) requires that contractors use engineering and work practice controls to reduce exposure to the lowest level practical.
Required by some owners in initial project bid documents.
Worker exposure can be reduced or eliminated by:
- engineering controls, such as a vacuum attachment to a pneumatic hammer
- work practice controls such as spraying water before performing any silica generating activities

Overview of the Tasks

1. Planning

2. Writing a site specific program
3. Implementing

4. Evaluating

a) Assess effectiveness of controls — This Guide will elaborate on these tasks —

Engineering and Work Practice Control Project Timetable

Owner issues bid documents with specifications for worker protection from crystalline silica.

Bid awarded; contract includes provisions for silica dust control plan. Contractor develops initial compliance program.

Project starts. Contractor develops site-specific silica health & safety program; engineering and work practice controls in place.

Silica Program Manager (SPM) reviews silica air monitoring results and makes regular site inspections.

SPM assesses effectiveness of controls and tries other strategies if necessary. Updates compliance program.

Project complete. SPM reviews effectiveness of controls. Owner modifies specifications for future projects, if necessary.

Planning

Planning the engineering and work practice control program is part and parcel of project planning. A timeline for the planning stage looks something like this:

Owner issues bid documents with specifications for worker protection from crystalline silica.

Bid awarded; contract includes provisions for silica control plan. Contractor develops initial OSHA compliance program.

Who is responsible for planning

Can be any of the following:
- Project planners
- Managers
- Company health and safety officer
- Silica Program Manager (SPM)
- Union superintendent

What plans need to be made

Assign a SPM to organize and run the program (usually assigned by central office or project manager).
Identify silica-generating tasks
Select one or several control options for each task. See the Silica Controls Selection Chart in Section 5.
- On most rehabilitation projects a combination of controls may be necessary.
- When selecting controls consider site-specific factors and schedules (e.g. are there factors which make the use of water undesirable - temperature, slip hazards).
Prepare a Compliance Program.

When to plan

Methods of controlling silica dust should be included in the initial project plans.
- Planners should look at the different silica disturbing tasks and select the best control options available to them.

Writing a Site Specific Compliance Program

The compliance program describes the engineering and work practice controls used at the site and includes records of compliance activities. The written program should include:

Introduction: Project description, location, scope and schedule of work.
Personnel: Project Manager, Silica Program Manager or industrial hygienist.
Silica dust-emitting activities: Describe tasks, equipment, materials used, work crew.
Engineering and work practice controls: Describe type of control, equipment, use and maintenance procedures. Include rationale for selecting each control and alternative technologies considered.
Personal air monitoring results: Provide industrial hygiene reports and air sampling results for silica dust-emitting activities. Refer to the Guide for Managing Exposure Assessment.
Schedule: Provide timetable for implementing compliance program.
Interim controls: Describe respiratory protection and other controls that will be used for each task. Refer to the Guide for Managing Respiratory Protection
Hygiene procedures: Describe protective clothing and equipment, housekeeping, clean areas, showers, and hand washing stations.
Worker rotation schedule: (if applicable).

Attach the following programs and records:

Respirator Program: Provide written program and identify program administrator, include respirator type selected for each task, records for training, fit testing, and medical clearances.
Training: Schedules, topics covered and records.

Section 2 Notes

Information on controls is available from a variety of sources. See the Resource List.
The written compliance program must be revised & updated periodically to reflect the current status of the program.

Implementing

Managing the Control Plan

Each of the activities listed below requires periodic inspection by the SPM. A timeline for control implementation looks something like this:

Project starts. Interim controls in place; contractor develops site-specific silica health & safety program; engineering and work practice controls in place.

SPM reviews silica air monitoring results and makes regular site inspections.

Making the control plan work:

Check that control equipment and supplies are on site before silica dust disturbing tasks begin.
Train workers and supervisors on how to use control equipment.
Inspect site frequently to ensure that controls are:
- present at the location where the tasks will be performed on any given day
- in operating order
- being used when they should be
- being used properly (provide additional training if necessary)
- effective (that is controlling dust emissions)

Use the Silica Controls Selection Chart in Section 5.

Section 6 contains Checklists that can be used by the SPM for conducting inspections.

Section 3 Notes

Selecting a control is the first step in protecting workers from silica containing dust - making it work is the second. A control program must be closely managed to be effective. For each control selected, the SPM should consider exposure factors, work procedures and should evaluate the effectiveness of the control. Weekly toolbox talks are a good time to review the use of new tools or controls.
Caution: Performing silica dust disturbing activities in an enclosed or confined space may greatly increase exposure.

Evaluating

Evaluating the control program is an ongoing activity as shown in the time line below.

Contractor assesses effectiveness of controls and tries other strategies if necessary. Updates compliance program.

Project complete. SPM reviews effectiveness of controls. Owner modifies specifications for future projects, if necessary.

There are 2 ways to evaluate whether the control program is working:

Site inspections of the controls - use Checklists in Section 6
Monitoring worker exposure to airborne silica dust while a control is being used (see Guide for Managing Exposure Assessment).

If the evaluation indicates a potential problem with a control check these possibilities:

Control is not appropriate for the job. Seek an alternate control.
Control is not functioning properly.
Workers are not using control properly.

Section 4 Notes

Upon completion of the project, it is advisable to prepare a final effectiveness report for future projects.

Silica Controls Selection Chart

Task/Tool	Control	Notes
Abrasive blasting	Substitute for sand	Alternate blasting agents with dust suppressant additives are widely available. Some, such as coal slag, might contain toxic materials
Jackhammer, pneumatic chipping gun	Wetting, vacuum attachment	Attachments that provide a fine water spray are currently being developed. Operators can also wet the surfaces with water from spray can, watering truck or hose prior to chipping. Care must be taken since some surfaces may not absorb water and frequent spraying may be necessary. Some workers don’t like wetting because they can’t see the work. Depending upon the location and/or time of year water can be a slip hazard due to mud or ice. Vacuum attachments are available but not widely used.
Pneumatic drill	Wetting, vacuum attachment	Water hose attachments are available Refer to above for additional options.
Power saws	Wetting	Attachments for concrete saws are available and in use.
Rock crusher	Wetting, distancing	Hose/spray assemblies available for wetting dust generated during rock crushing. Remote control devices can help reduce operator exposure.
Grinder, tuck pointing	Wetting, vacuum attachment	Vacuum attachment available although not widely used. Wetting of surfaces works but often discouraged because of surface run-off and slurry created.
Operating heavy equipment	Air-conditioned cab with HEPA filters	Keep doors, windows closed and air conditioning filter on.
Cleaning surfaces and clothing	HEPA vacuums, water spray	Compressed air should not be used to clean surfaces or clothing. Mechanical cleaning machines not using water will create dust clouds. Use vacuum for smaller size debris, a shovel should be used for larger pieces that may clog the vacuum. Maintain adequate vacuum capacity. Use prefilters to extend the service life of HEPA filters.
General work area	Water truck with spray nozzles	Frequent spraying of work area to keep surface damp

Checklists

Suggestion on using checklists: since these lists are short, they can be made smaller and placed or pasted into field notebooks. For instance, Checklist 1 could be miniaturized - see example at end of checklists. They can also be programmed onto a PDA (Personal Digital Assistant).

CHECKLIST 1. SITE INSPECTION (for all controls)

Controls are:	Y/N	Problem noted (describe)	Problem fixed (describe)
Available at work location
In operating order
Used when they should be
Used properly (workers trained in their use)
Effective in controlling dust emissions

CHECKLIST 2. CLEANING UP DEBRIS WITH HEPA VACUUM

	Y/N	Problem noted (describe)	Problem fixed (describe)
Vacuum is operated as per manufacturer's instructions
Large pieces of debris have been picked up with shovel prior to use of vacuum (so that vacuum doesn't get clogged).
Adequate vacuum capacity maintained
Prefilters in place
Wide mouthed attachments and rigid wands in use. Workers able to operate vacuum without stooping over
Collection bags in place, bags disposed of properly

MINIATURIZED CHECKLIST 1. SITE INSPECTION (for all controls)

Controls are:	Y/N	Problem noted (describe)	Problem fixed (describe)
Available at work location
In operating order
Used when they should be
Used properly (workers trained in their use)
Effective in controlling dust emissions

Back to Guides for Managing Crystalline Silica Control Programs in Construction

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