OSHA s Proposed Silica Rule 1910.1053 Randy Nicholls Northwestern Energy
Exposure Limit Comparison Previous Permissible Exposure Limit from Table Z- 3, Mineral Dusts, had to be calculated as follows: Quartz (Respirable) 10 mg/m 3 %SiO2 + 2 Quartz (Total Dust) 30 mg/m 3 %SiO2 + 2 Proposed Rule establishes new fixed PEL and Action Limit for respirable crystalline silica. PEL (8 hour TWA) 50 µg/m 3 AL (8 hour TWA) 25 µg/m 3
Exposure Limit Comparison Previous calculated PEL s allowed exposures (depending on the % Quartz) up to an order of magnitude higher than the proposed PEL. Example: Dust contains 15% Quartz. Calculated PEL = 10 mg/m 3 10 15%SiO2 + 2 = 17 = 0.588 mg/m 3 = 588 µg/m 3 Proposed PEL 50 µg/m 3
EEI Silica Sampling Data Results of 1565 personal respirable silica air samples were submitted. Of these, 74 or 4.73% of the samples in the study exceeded the proposed PEL of 0.05 mg/m3 (all are 8 hr. TWA). An additional 32 samples exceeded the Action Level, but were below the PEL. A total of 106 or 6.77% samples were at or above the Action Level.
EEI Silica Sampling Data Type of Work > PEL >AL but <PEL Coal Yard Work 27 9 36 Maintenance Work including construction and outage activities Operations Work - such as precipitator maintenance & cleaning Other - blowing dust, pulverizing coal samples 34 17 51 8 3 11 5 3 8 TOTALS 74 32 106 Total >AL
Initial Exposure Assessment Must assess the exposure of employees who are or may reasonably be expected to be exposed to respirable crystalline silica at or above the action level. Determine employee exposures from breathing zone air samples that reflect the 8-hour TWA exposure of each employee. Determine the exposures of employees on each shift, for each job classification, in each work area.
Initial Exposure Assessment May rely on existing data to satisfy the initial monitoring requirement where the employer: Has monitored employee exposures after (12 Months prior to effective date of final rule) under conditions that closely resemble those currently prevailing; or Has objective data that demonstrate that respirable crystalline silica is not capable of being released in airborne concentrations at or above the action level.
Periodic Exposure Assessment If initial monitoring indicates that exposures are below the action level, may discontinue monitoring for those employees whose exposures are represented by such monitoring. If initial monitoring indicates that exposures are at or above the action level, must continue to monitor either under the fixed schedule or performance-based options.
Employee Notification of Assessment Results Within 15 working days after completing an exposure assessment, each affected employee must notified in writing of the results of that assessment or post the results in an appropriate location accessible to all affected employees. Whenever the exposure assessment indicates that employee exposure is above the PEL, the written notification must describe the corrective action being taken to reduce employee exposure to or below the PEL.
Fixed Schedule Option Where initial or subsequent exposure monitoring reveals that exposures are at or above the action level but at or below the PEL, repeat monitoring at least every six months. Where initial or subsequent exposure monitoring reveals that employee exposures are above the PEL, repeat monitoring at least every three months. Can discontinue monitoring at the required frequency if at least two consecutive measurements, taken at least 7 days apart, are below the action level.
Performance Option Assess the 8-hour TWA exposure for each employee on the basis of any combination of air monitoring data or objective data sufficient to accurately characterize employee exposures. What would this look like? Will need good written documentation
Additional Exposure Assessments Must conduct additional exposure assessments whenever a change in the production, process, control equipment, personnel, or work practices may reasonably be expected to result in new or additional exposures at or above the action level.
Laboratory Requirements Follow procedures specified in one of the specified analytical methods: OSHA ID-142; NMAM 7500, NMAM 7602; NMAM 7603; MSHA P-2; or MSHA P-7. Be accredited to ANS/ISO/IEC Standard 17025:2005 with respect to crystalline silica analyses by a body that is compliant with ISO/IEC Standard 17011:2004 for implementation of quality assessment programs Follow other QA/QC requirements listed in the Silica Standard
Regulated Areas & Access Control If exposures are in excess of the PEL, must establish and implement either a regulated area or an access control plan.
Regulated Area Option Demarcate regulated areas from the rest of the workplace in any manner that adequately establishes and alerts employees to the boundaries. Limit access to regulated areas to: Authorized persons required to work in the regulated area; A designated representative of employees for the purpose of exercising the right to observe monitoring; and Any person authorized by the Occupational Safety and Health Act or regulations issued under it to be in a regulated area
Regulated Area Option Provide appropriate respirators and establish a respiratory protection program in accordance with 1910.134. If work clothing can become grossly contaminated with finely divided material, provide either of the following: coveralls or similar full-bodied clothing; or Means to remove excessive silica dust from contaminated clothing that minimizes employee exposure. Must ensure that such clothing is removed or cleaned upon exiting the regulated area and before respiratory protection is removed.
Written Access Control Plan Option The written access control plan shall contain at least the following elements: Provisions for a competent person to identify location of any areas where exposures are, or can reasonably be expected to be, in excess of the PEL; Procedures for notifying employees of the location of areas identified and for demarcating such areas where appropriate; For multi-employer workplaces, the methods to inform other employer(s) of the location of those areas and any precautionary measures that are needed; Provisions for limiting access to identified areas
Written Access Control Plan Option PPE requirements are the same as for Regulated Areas Must review and evaluate the effectiveness of the written plan at least annually. Must make the plan available to employees and their designated representatives.
Methods of Compliance Engineering and Work Practice Controls Use engineering and work practice controls to reduce and maintain employee exposure to or below the PEL, unless the employer can demonstrate that such controls are not feasible. When feasible engineering and work practice controls are not sufficient to reduce exposure to or below the PEL, must still use them to reduce employee exposure to the lowest feasible level and supplement with a respiratory protection program.
Engineering Control Example
Engineering Control Example
Methods of Compliance Abrasive Blasting Must comply with the other OSHA standards specific to this activity. Cleaning Methods Use HEPA-filter vacuuming or wet methods to clean up accumulations of crystalline silica. Do not use compressed air, dry sweeping, or dry brushing to clean clothing or surfaces contaminated with crystalline silica. Prohibition of Rotation Cannot rotate employees to different jobs to achieve compliance with the PEL.
Medical Surveillance Provide medical surveillance at no cost to the employee, and at a reasonable time and place, if exposed above the PEL for 30 or more days per year. Ensure that all medical examinations and procedures are in accordance with requirements of paragraph (h) of the standard. Appendix A to 1910.1053 provides non-mandatory medical surveillance guidelines
Hazard Communication Include respirable crystalline silica in your Hazard Communication Program. Ensure access to labels on containers of crystalline silica and safety data sheets. Hazards to be addressed must include: Cancer Lung effects Immune system effects Kidney effects.
Information and Training Employee must demonstrate knowledge of at least the following: Specific operations in the workplace that could result in exposure to respirable crystalline silica Specific procedures to protect employees from exposure The contents of the Silica Standard The purpose and description of the medical surveillance program
Recordkeeping Air monitoring data Maintain an accurate record of all exposure measurements. The date each sample was taken; The operation monitored Sampling and analytical methods used and identity of the laboratory that performed the analysis Number, duration, and results of samples taken; Type of personal protective equipment worn by the employees monitored Name, social security number, and job classification of all employees represented by the monitoring and which employees were actually monitored.