ESH Manual Page: 4000: Industrial Hygiene

ESH Manual Table of Contents

Chapter: Lead (Pb) Program

1.0 POLICY 

This document outlines the guidelines and requirements for safe work with lead and lead compounds. The information in this chapter applies to general industry and construction work.  General industry work generally includes handling lead shielding, building experimental equipment, soldering, and machining lead or lead alloys (including brass and pewter).  Construction work includes maintenance, demolition or remodeling of buildings; new building construction; removal of lead paint from equipment or buildings; and the use of paint or other materials that contain lead.

Use and handling of lead and lead compounds at the Sanford Laboratory follow the criteria in the Occupational Safety and Health Administration (OSHA) Laboratory Standard (29 Code of Federal Regulations (CFR) 1910.1450) – except that the general industry permissible exposure limit is applied.

2.0 SCOPE

All Sanford Underground Laboratory at Homestake (hereafter referred to as Sanford Laboratory) employees, participating guests, students, supplemental labor workers and contractors (also known as Laboratory Personnel) must follow the applicable portions of the procedures outlined in this document when performing lead work.

3.0 RESPONSIBILITIES

3.1. EHS Department

The EHS Department is responsible for:

  • Revising the lead (Pb) program as needed;
  • Developing and implementing training;
  • Working with appropriate staff to identify hazards, ensure proper sampling is conducted, & establish appropriate controls; and
  • Identifying an appropriate medical monitoring provider if medical monitoring is needed.

3.2. IH/Safety TechnicianThe IH/Safety Technician is responsible for:

  • Performing or overseeing lead (Pb) testing; 
  • Notifying supervisors and personnel of monitoring results; 
  • Verifying that added controls are sufficient to reduce exposure below OEL limits;
  • Recommending engineering or administrative controls to lead (Pb) hazards; 
  • Recommending warning signs where appropriate; 
  • Maintaining industrial hygiene survey records, notifications of personal monitoring memos, and equipment calibration logs; 
  • Providing updated hazard information for site-specific training; and
  • Reviewing plans for new operations and significant changes to ongoing operations that may create lead (Pb) hazards.  

3.3. Laboratory Personnel
All Laboratory Personnel are responsible for: 

  • Completing required training in lead (Pb) hazards and personal protective equipment (PPE) usage before working;
  • Receiving medical monitoring and sampling of work tasks as required;
  • Using controls, including  personal protective equipment provided;
  • Reporting suspected exposures to supervisors and/or to the EHS Department.

3.4. Project Managers
Project Managers are responsible for:

  • Reviewing proposed processes involving lead (Pb) hazards with the EHS Department before installing new or moving existing equipment; 
  • Working in conjunction with various departments and the involved contractor(s) to ensure engineering controls are meeting minimum performance standards and effectively preventing personnel over-exposure to lead (Pb) hazards; 
  • Reporting deficient engineering controls to the proper authority for repairs;
  • Following up on recommendations provided by the EHS department staff; 
  • Ensuring areas where lead (Pb) hazards are found have the proper warning signs displayed, in consultation with the EHS department; 
  • Choosing less-hazardous design options whenever possible, in consultation with the EHS department; and
  • Including qualitative exposure assessment of lead (Pb) hazards during the development and annual review of JHAs;

3.5. Supervisors
Supervisors are responsible for:

  • Reviewing proposed processes involving lead (Pb) hazards with the EHS Department before installing new or moving existing equipment; 
  • Working in conjunction with various departments to ensure engineering controls are meeting minimum performance standards and effectively preventing personnel over-exposure to lead (Pb) hazards; 
  • Reporting deficient engineering controls to the proper authority for repairs;
  • Following up on recommendations provided by the EHS department staff; 
  • Ensuring areas where lead (Pb)  hazards are found have the proper warning signs displayed, in consultation with the EHS department; 
  • Choosing less-hazardous design options whenever possible, in consultation with the EHS department; and
  • Including qualitative exposure assessment of lead (Pb) hazards during the development and annual review of JHAs;
4.0 DEFINITIONS

Action Level: An OSHA occupational exposure limit (without regard to the use of respirators) for airborne contaminants.  For lead it is 30 micrograms per cubic meter of air (30 µg/M3) for an 8-hour Time-Weighted Average (TWA).  Employees whose exposure is above the Action Level for more than 30 days per year are required to be in a medical surveillance program.

Affected Employee: Any employee whose exposure is at or above the Action Level.

ALARA: As Low As Reasonably Achievable.  Sanford Lab policy is to keep employee chemical exposure as low as feasible.

HEPA: A High Efficiency Particulate Air Filter capable of filtering 0.3 micron particles with 99.97 percent efficiency.

Lead (Pb): Metallic lead, all inorganic lead compounds (e.g., laboratory reagents, solder), and organic lead soaps.  All other organic lead compounds, such as tetraethyl lead, are excluded from this definition.

Lead Paint: Paint containing greater than 0.06 % (600 ppm) lead.

Medical Surveillance: Consists of medical examinations as well as blood sampling for lead and zinc protoporphyrin, if applicable.  Performed by or under the supervision of a physician. 

Occupational Exposure Limit (OEL): An exposure limit that is the lower of the permissible exposure limit or threshold limit value (see permissible exposure limit).

Permissible Exposure Limit (PEL): An OSHA occupational exposure limit (without regard to the use of respirators) for airborne contaminants.  For lead it is 50 micrograms per cubic meter of air (50 µg/m3) for an 8-hour Time-Weighted Average (TWA).  Exposure to airborne lead above the PEL triggers requirements such as housekeeping, engineering controls, showers, change and lunch rooms, area posting, personal protective equipment, and respiratory protection.

Personal Protective Equipment (PPE): Personal Protective Equipment.  Safety equipment worn by employees; may include safety glasses, respirators, coveralls etc.

5.0 CONTROLS FOR LEAD (Pb) OPERATIONS

5.1. Air Exposure Limits and Biological Exposure Indices

Exposures to airborne lead and biological monitoring are evaluated against, and controlled below, the following regulatory limits:

5.1.1. Elemental and Inorganic Lead

  • 29 CFR 1910.1025, “Lead.” This standard applies to elemental lead, all inorganic lead compounds, and lead soaps, in non-construction work environments. It does not apply to other organic lead compounds. The OSHA 8-hour time-weighted permissible exposure limit (PEL) for metallic lead, any inorganic lead compound, or lead soaps is 50 ug/m3 of air averaged over an 8-hour period. The action level is 30 ug/m3 of air averaged over an 8-hour period. Employees who will be potentially exposed above the action level must be enrolled in the Lead Medical Surveillance Program.  (See HR or EHS Department for details.) Those working with lead under 30 days per year may enroll upon request.
  • 29 CFR 1926.62, “Lead.” This is the Federal OSHA construction standard that establishes the medical surveillance trigger for workers exposed  on any single day to lead at or above the action level (30 ug/m3), and that is followed for any Sanford Lab employee (or contractor) conducting “construction”-related work.
  • ACGIH, “Biological Exposure Index (BEI)” for Lead, as established by the (ACGIH) Threshold Limit Values. The ACGIH BEI for lead in blood is 30 ug/100ml.

5.1.2. Tetramethyl and Tetraethyl Lead

  • 29 CFR 1910.1000, “Air contaminants.” The corresponding 8-hour time-weighted PEL for tetramethyl and tetraethyl lead is 75 ug/m3 of air. There is no PEL for other organic lead compounds.
  • American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Values, “Air contaminants.” Exposure limits for tetraethyl lead (100 ug/m3 and tetramethyl lead (150 ug/m3). Note:  Exposure to these chemicals should be limited to 75 ug/m3, the applicable OSHA Standard for general industry.

5.2. Surface Contamination Limits

When lead-containing materials are disturbed, residual surface contamination may pose a hazard to people who subsequently occupy the area. Additionally, break areas should remain free of harmful levels of lead. In such cases, surface sampling is sometimes conducted, as determined by the EHS Department.

Generally, the following swipe criteria would be applied:

  • <200 ug/ft2 for change areas, storage facilities, and lunchrooms/eating areas.

Similarly, a housekeeping level for established lead work areas that may be used is:

  • <1800 ug/ft2 on work surfaces in a designated area.

This latter value is a housekeeping level that defines whether a designated lead work area is in need of cleaning.

For work and break areas at Sanford Lab, a higher or lower limit may be acceptable at the discretion of the EHS Department.

5.3. Exposure Controls

The Sanford Lab Lead Compliance Plans in Appendix B (or similar documentation) outline the specific requirements for lead work at Sanford Lab for work that may cause an exposure over the PEL. These Lead Compliance Plans must be reviewed on a regular basis for lead work not associated with buildings (if the plans are still in effect). General work requirements, for all jobs are included in this section. Lead Compliance Plans should be developed by the organization planning and conducting the work.

A separate Lead Compliance Plan is not required for jobs with a Negative Exposure Assessment (NEA), such as those in Appendix A.

5.3.1. Housekeeping and Decontamination

Surfaces should be maintained as free as practicable from accumulation of lead.  Shoveling, blowing, wet or dry sweeping, and/or blowing of lead-containing dusts is not allowed unless specifically approved in the Lead Compliance Plan.  
Contaminated work surfaces should be cleaned sufficiently to reduce lead levels to less than 1800 ug/ft2. A different level may be accepted for industrial or laboratory areas, at the discretion of the
EHS Department. Recommended cleanup methods include vacuuming the area with a high-efficiency particulate air (HEPA)-filtered vacuum or wet-wiping with disposable cloths. Consult the EHS Department to determine the proper waste disposal practices.

5.3.2. Personal Hygienic Practices

The precautions below apply to areas where lead is disturbed, and where the potential for exposure is greater than the PEL.

  • Designate a separate location for eating, storing, and preparing food and beverages and cosmetics to avoid the possibility of ingesting lead. No lead work shall be performed in these designated areas. Lunchrooms shall be kept under positive pressure by the provision of tempered, filtered air. 
  • Wash hands and face before eating, drinking, or applying cosmetics.  (Workers should shower if exposed in excess of the PEL.) Do not wear protective clothing into lunchrooms.
  • Designate change rooms where workers can segregate street clothes from clothing used for work.
  • Make shower facilities available. Showers located throughout the Sanford Lab drys may be used, provided that other workers do not use these showers while they may be potentially contaminated with lead dust. Showers used by lead workers should be decontaminated before used by other workers. Portable shower units should be used for required decontamination activities.
  • Promptly place lead-coated or lead-containing demolition or renovation debris (e.g., sheet rock) in plastic bags or other sealable containers. Do not allow them to accumulate in the workspace. These bags should be labeled in accordance with any Sanford Lab environmental guidance. Consult your supervisor or the EHS Department to determine exact requirements.

5.3.3. Regulated Areas

Signs, with the wording below, shall be posted at all possible entrances in “Regulated Areas” (i.e., locations where lead work or lead use is being conducted).  These signs should be designed in accordance with the OSHA or ANSI design criteria and color scheme. These signs shall be easily visible to workers and visitors. Contact the EHS Department for guidance if you have any questions about signs. Refer to Appendix D for an example of the required sign.
 
WARNING
LEAD WORK AREA
POISON
NO SMOKING OR EATING

  5.3.4. Personal Monitoring Program

Personal air sampling shall be conducted to assess an individual’s (or group’s) exposure to airborne lead during work that disturbs lead-containing materials. Initial samples are required for all operations where exposure above the action level may occur. The frequency of subsequent sampling depends on the results of the initial samples.
The process of initiating and collecting air samples is as follows:

  • Work supervisors shall notify the IH/Safety Technician at least 48 hours in advance of planned lead operations so that air sampling can be arranged.
  • The IH/Safety Technician or a technician working under the guidance of the IH/Safety Technician shall do the following:
    •  Collect the initial personal air samples for uncharacterized operations that may generate airborne lead, and submit them to an accredited analytical laboratory for analysis.
    •  If the results of the representative samples are below the action level, no further sampling is required as long as the operation continues unchanged.  If the results are above the action level but below the PEL, air sampling must be repeated at least every 6 months. For results greater than the PEL, air sampling must be repeated every three (3) months, and a written compliance plan detailing the steps to be taken to reduce the airborne lead levels must be developed and implemented.
    • The results of air sampling conducted to measure exposure during operations at the lab site may be used to represent the level of exposure for other similar operations. The decision to accept these results, however, is at the discretion of the EHS Department.

 For more complete details on lead exposure assessment, contact the EHS Department or refer to the appropriate OSHA lead standard.

5.3.5. Surface Contamination Sampling

Floors and other surfaces in work areas where significant lead is disturbed should be tested for residual lead contamination before workers re-occupy those areas. Specifically, this guidance applies when the work involves any of the activities listed in Appendix B, when the work is lead hazard abatement or involves exposure above the action level and when the work area is inside and will subsequently be re-occupied on a regular basis.

These samples are usually obtained by making two S-shaped swipes with a pre-wetted wipe at a 90º angle over a 1-ft2 area and submitted to an Analytical Laboratory for analysis. Details on this sampling method can be found in the HUD “Guidelines for the evaluation and control of lead based paint hazards in housing.” Samples are generally collected by EHS Staff.

Clearance swipe samples, where required for work performed by contractors, shall be obtained and analyzed by the contractor in accordance with the HUD Guidelines. However, Sanford Lab reserves the right to request changes in the sampling and analysis procedure or to obtain parallel clearance samples.

The analytical laboratory must be accredited by the American Industrial Hygiene Association or another organization accredited by the EPA specifically to perform lead analyses.

5.3.6. Application  and Installation of Lead-Containing Products

With the exception of lead solder in electrical work, materials containing more than 0.06% lead should not be used, specified or allowed in the construction of buildings or infrastructure.  Requests for a special allowance require prior review of the EHS Department and the Operations Department.

5.3.7. Lead Paint Abatement

Lead abatement refers to construction activities undertaken specifically to remediate an imminent or potential hazard to humans or the environment from lead paint. This may include the removal, enclosure or encapsulation of paint.

Lead-abatement work performed by Sanford Lab personnel or supplemental labor workers should be evaluated by the EHS Department for determination of appropriate controls.  A lead compliance plan is normally required for lead-abatement work.

Contracted lead-abatement work should be conducted by a licensed contractor and in accordance with the Housing and Urban Development (HUD) Guidelines.

Indoor lead-abatement areas should be subjected to a final visual inspection and final surface sampling in accordance with the HUD Guidelines.

5.3.8. Preconstruction Paint Sampling

Lead may be present in paint on the surfaces of many Sanford Lab buildings. Thus, it is necessary to identify activities such as maintenance, renovation, remodeling and demolition that will disturb lead-coated surfaces so that the appropriate controls can be implemented before work begins. It will be necessary to test the interior and exterior of most building surfaces before beginning activities that disturb potential lead-containing material or it may be assumed that the material disturbed includes lead.

Specifically, painted surfaces should be tested before beginning construction activities that involve:

  • Scraping, abrasive blasting or sanding
  • Demolishing buildings
  • Cutting, sawing or otherwise penetrating a wall or other painted surface—except for installing a few screws into a wall
  • Burning, torch cutting, arc cutting, welding or brazing
  • Using a heat gun to remove paint
  • Performing other activities that generate lead-containing dust

 Testing should also be conducted on other potentially lead-containing construction materials if a lead aerosol may be generated, including but not limited to:

  • Galvanized metal that is to be cut with a torch, burned, power sawn, or otherwise heated to the melting point of lead
  • Brass, bronze, and pewter to be sanded or heated to the melting point of lead
  • Solders to be sanded

Laboratories that analyze lead swipe or bulk samples must be accredited by the American Industrial Hygiene Association or another organization accredited by the EPA specifically to perform lead analysis. Bulk samples can be analyzed using atomic absorption or inductively coupled plasma emission spectroscopy (ICPES). Alternative techniques (e.g., laboratory or field x-ray fluorescence) may be approved by the EHS Department.

Work Performed by Laboratory Personnel. Preconstruction testing is conducted by either Sanford Lab personnel or consultants who (1) complete the State Accreditation Program for Lead Inspectors or are certified by the American Board of Industrial Hygiene in industrial hygiene, or (2) work under the supervision of a Certified Industrial Hygienist or an accredited inspector.

Work Performed by Contractors. Sanford Lab shall either (1) test all potentially lead-containing surfaces before releasing a construction proposal for work that may disrupt lead, or (2) require the contractor to perform the test(s) before disrupting any potentially lead-containing materials. Contractors who make lead determinations must be accredited as lead building inspectors, or the work must be conducted directly by a Certified Industrial Hygienist.

5.3.9. Lead Shielding

Where it will not interfere with their shielding properties, lead items used for shielding or weighting should be encapsulated in a suitable coating to protect the lead from corrosion and to reduce worker contact. Corroded lead materials may be particularly hazardous and should be encapsulated or replaced if feasible. Newly purchased shielding bricks should be encapsulated to prevent oxidation.

6.0 TRAINING (All training programs are currently under development)

The Sanford Lab lead training program is based on the type(s) of tasks conducted, as follows:
Workers only doing light, non-routine electrical soldering may be trained in:

  • Soldering Hazard Awareness

Workers who perform work under another established Negative Exposure Assessment (NEA, see Appendix A) should be trained in either:

  •  Hazard Communication Training for Lead or
  • Lead Worker Training

Work in laboratories with lead or lead-containing compounds normally only require completion of Chemical Hygiene and Safety Training or Sanford Lab Hazardous Waste Training, though if extensive lead work may be performed (such as experiments with lead batteries or extensive handling of lead bricks or other shielding) additional training may be required. Please refer to the Safety Manual or the EHS Department for more information.

If more extensive training or certification is necessary based on risks of the activity, additional training may be required, such as:

  • Lead Construction Supervisor,
  • Lead-Construction Worker, and
  • Lead-Construction Refresher

 Some of these courses are not usually taught on site.

7.0 PERSONAL PROTECTIVE EQUIPMENT (PPE)

Personal protective equipment (in addition to normal work requirements) may include coveralls, shoe covers, head covers, gloves and respirators and is required for operations that may generate airborne lead levels above the PEL (50 µg/m3). Safety shoes may be required for some operations.  Leather gloves (or equivalent) shall be used when handling unencapsulated lead bricks or shielding. Additional requirements may be applicable if the exposure is known or expected to exceed 200 µg/m3. When required, special equipment may be defined by the Hazard Analysis or Lead Compliance Plan that is reviewed and approved by the EHS Department or an Industrial Hygienist.

7.1 Protective Garments

Workers are usually issued disposable work coveralls in lieu of reusable coveralls. These coveralls shall not be worn home. Reusable clothing must comply with the cleaning and replacement requirements in the standards, including having the following label:

7.2 Respiratory Protection

The EHS Department shall select respirators, except those for contractors, in conformance with the Sanford Lab Respiratory Protection Program (under development).  No worker shall be required to wear a negative-pressure respirator for more than 4 hours a day when feasible engineering controls are in place. Fit-testing of respirators, where required, must be conducted within twelve (12) months prior to lead work. 

8.0 REFERENCE AND RELATED DOCUMENTS

8.1. Standards

  • 29 CFR 1910.1025 - Lead
  • 29 CFR 1910.1000, Air contaminants 
  • 29 CFR 1926.62 - Lead
  • ACGIH, Biological Exposure Index (BEI) for Lead
  • American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Values, Air contaminants

8.2. Related Documents

  • Respiratory Protection Policy (under development)

8.3. Appendices

  • Appendix A:  Negative Exposure Assessments (NEAs)
  • Appendix B:  Lead (Pb) Compliance Plan / Lead Work Permit
  • Appendix C:  HEPA Vacuum Safe Work Procedure
  • Appendix D:  Lead (Pb) Work Area Warning Sign and Label for Contaminated Clothing