The Hierarchy of Controls
When workplace lead levels exceed the Permissible Exposure Limit (PEL), employers must implement feasible control measures to reduce and maintain employee exposures at or below the PEL. OSHA and ANSI/ASSP Z10 standards recommend using a prioritized “Hierarchy of Controls” (HOC) to systematically minimize hazards. The six levels of control are described below:
1. Elimination
- The most effective strategy, as it completely removes the hazard from the workplace.
- Examples: Using lead-free abrasives, lead-free solder, or lead-free paints.
2. Substitution
- If elimination is not possible, replace the hazardous material or process with a less hazardous one.
- Example: Replacing a highly toxic chemical with a less toxic alternative.
3. Engineering Controls
- These controls isolate employees from the hazard or modify equipment or processes to reduce exposure.
- Examples: Local exhaust ventilation, enclosures, or isolation of lead-generating processes.
4. Warnings
- Alerts that make employees aware of hazards and encourage precautionary behaviors.
- Examples: Signage, barrier tape, alarms, and hazard labels.
5. Work Practice Controls
- Procedures or behaviors designed to limit exposure.
- Examples:
- Limiting the time a worker spends on tasks involving lead.
- Maintaining good housekeeping to prevent lead contamination.
- Providing hygiene facilities and practices to prevent ingestion or take-home exposure.
6. Personal Protective Equipment (PPE)
- Used when other controls cannot fully eliminate exposure.
- Examples: Respirators, protective clothing, gloves, and eye protection.
- Employers must ensure PPE is provided, properly used, and maintained when required.
Important Note:
- When all feasible engineering and work practice controls have been implemented but are still insufficient to meet the PEL, respiratory protection must be provided and used.
- Interim Measures: Temporary controls may be used while a permanent solution is being implemented. These may involve a combination of the control methods above to reduce exposure until the hazard can be fully addressed.