When a reasonable suspicion of hazard exists, industrial hygiene (IH) monitoring of workplace chemical and physical exposures is required by regulation, standards, and good business practice
When a reasonable suspicion of hazard exists, industrial hygiene (IH) monitoring of workplace chemical and physical exposures is required by regulation, standards, and good business practice. Monitoring data are required for employee exposures to total dust, respirable dust, and dust components, such as free respirable silica and portland cement particles. Also potentially hazardous are chrome VI welding fumes and noise.
For any worker in an environment where possible exposure to a health hazard exists, the employer must determine if the employee is subject to exposure exceeding the regulatory Permissible Exposure Limit (PEL). Failure to collect exposure data in such a situation constitutes regulatory noncompliance and may lead to employer liability Û not to mention potential employee hazards.
Problems associated with monitoring data and its interpretation are generated by the complexity of data-collection methodologies and documentation requirements. Corrupted data commonly involve incorrect assessment using inappropriate media; unrepresentative exposure monitoring; failure to identify exposures after corrective measures are implemented; use of an unqualified industrial hygienist; inaccurate Threshold Limit Value calculations; or, the maintenance of poor equipment-calibration records.
Producers should be aware that collecting bad data is usually more problematical than collecting no data at all. Because erroneous data collection or poor data maintenance entails the risk of liability as it jeopardizes employee health, the importance of accurate monitoring data Û obtained by personnel of valid credentials and thoroughly documented Û cannot be overstated. Moreover, when workers fail to recognize the urgent need communicated by an employer’s drive to reduce exposure levels, they may continue to operate heedlessly in a manner that exceeds PELs, thereby contributing to citations.
Most of the problems cited above can be avoided by using an independent industrial hygienist to collect data and issue a well-written report that includes site-collection observations, complete monitoring data, calibration records, and calculations. Also to be cited are the reporting professional’s credentials, since a certified industrial hygienist (CIH), recognized by the Board of Certified Industrial Hygienists, is best suited to the task. An acceptable alternative is monitoring by a qualified industrial hygienist under the oversight of a CIH; in that case, the document is signed by both the CIH and industrial hygienist who implemented data collection.
While material safety data sheets (MSDS) provide chemical exposure warnings, few people actually read MSDSs or completely understand the warnings, possibly because they typically are written in what may be perceived as an overly cautious manner for the manufacturer’s liability protection. Consequently, employers are advised to enlist an independent CIH to evaluate all work processes, including use of form-release agents, additives, and adhesives; welding exposures; concrete dust exposures generated by sawing, mixing, bulk transfer, and daily cleanup; plus, carbon and carbon monoxide exposures due to indoor mobile-equipment use and unventilated fuel-burning heaters in winter months, when doors are closed. Additionally, data should be obtained during summer months when bay doors are open. The difference in exposure due to varying seasonal operations may be relevant also to noise exposures, as fans can be used in summer months. Report documentation should identify environmental differences and why data are recorded on separate occasions.
Data-collection evaluation should include assessments of all jobs, since exposures will differ among various positions. Differences in exposure levels will be noted, for example, between operators of forklifts, mixers, and wire cage machines, as well as yard personnel. While many plants rotate workers, identifying which positions are subject to overexposures Û or nonexposures Û is nonetheless essential.
All exposure-monitoring data should be shared openly with employees, e.g., posting the report on the bulletin board for a period provides workplace transparency. Such reporting must include data taken both prior to and after implementation of abatement controls. Recommended for maintenance of compliant exposure levels are an annual review of the findings, consistent use of required abatement procedures, and employment of personal protective equipment (PPE).
In situations of overexposure, engineering controls must be employed before PPE is adopted as an alternative. Engineering controls need not entail an overly complicated nor costly system in most applications. Once an overexposure has been identified, many problems can be corrected by means of inexpensive fans, improved ventilation, or system leak repairs.
To maintain accurate records, periodic remonitoring is recommended, even when no change has been introduced in the working environment. Mandatory remonitoring, however, necessarily follows a change in the workplace, involving equipment, routines, or any other factor that may affect employee exposures.
The Occupational Safety and Health Administration (OSHA) announced that approximately 3,800 high-hazard worksites have been placed on a primary list for unannounced, comprehensive safety inspections over the coming year. Due to various silicosis initiatives identifying concrete production as a source of exposure, both safety and health inspections may be conducted for sites exceeding the incident-level threshold for inclusion on the list. Either a single safety-and-health inspection or separate safety and health investigations will be conducted.
Calculation of exposure level first requires a review of OSHA-300 Logs for 2005, 2006 and 2007, noting the DART (Days Away, Restricted, or Transfer) rate and DAFWII (Days Away From Work Injury and Illness) case rate for each of the three years. OSHA-300 logs for 2008 (and 2009 when applicable) also may be reviewed for possible injuries and illnesses.
The 2006 DART rate calculated by the OSHA inspector is compared to the DART rate reported by the employer as part of the OSHA 2007 Data Initiative. Calculations are not to be performed if, for any reason, relevant records are not available. Inspectors will check OSHA-301 Forms as they deem appropriate to confirm OSHA-300 Logs.
Selection criteria established by OSHA for inclusion of individual workplaces on the primary list target those sites exhibiting a DART rate at or above 11.0, or a DAFWII case rate at or above 9.0. Only one of the criteria must be met for eligibility. Reference points are determined by considering twice the 2006 national, private-sector incidence rates, i.e., DART rate, 2 _ 2.3 = 4.6; or, DAFWII case rate, 2 _ 1.3 = 2.6.
The following steps are employed:
If records are not available to make the determination, the regulator proceeds with the inspection.
If any two of the inspector-calculated 2005, 2006 or 2007 DART rates are at or above 4.6, then the inspection is conducted.
If any two of the above DART rates are below 4.6, but any two of the inspector-calculated DAFWII case rates are at or above 2.6, the regulator proceeds with the inspection.
If for any two of the above three years, DART rates are below 4.6, and DAFWII case rates for the same two years are below 2.6, then a records review (not a records audit, which requires the use of an audit software program) is in order for the most current year that falls below twice the private-sector 2006 national incidence rates, followed by a recalculation of DART and DAFWII for that year. If the DART is below 4.6 and the DAFWII is below 2.6, classify the inspection as records only and conduct a walkthrough inspection [as required by the second to the last paragraph in this section] before exiting the facility. If either the DART rate is at or above 4.6, or the DAFWII case rate is at or above 2.6, proceed with the inspection.
Calculating annual DART and DAFWII incident rates entails two procedures. The DART rate, which includes cases involving days away from work, restricted work activity, and transfers to another job, is determined on the basis of (N/EH) _ (200,000), where N is the number of cases involving days away and/or restricted work activity and/or job transfers; EH is the total number of hours worked by all employees during the calendar year; and, 200,000 is the base number of hours worked for 100 full-time equivalent employees. For example: Employees of an establishment, including management, temporary, and leased employees, worked 645,089 hours at the site. There were 22 injury and illness cases involving days away and/or restricted work activity and/or job transfer from the OSHA-300 Log (total of column H plus column I). The DART rate would be (22/645,089) _ (200,000) = 6.8.
The DAFWII case rate is the number of cases that involve days away from work per 100 full-time equivalent employees (cases involving only temporary transfers to another job or restricted work are not included in the calculation). It is calculated on the basis of (N/EH) _ (200,000), where N is the number of cases involving days away from work; EH is the total number of hours worked by all employees during the calendar year; and, 200,000 is the base number of hours worked for 100 full-time equivalent employees.
Thus, DART and DAFWII rates are differentiated by the makeup of N in their calculation formulas. N for the DAFWII rate is equal to the Column H total on the OSHA-300 Log. For example, the OSHA-300 Log indicates: Employees of an establishment, including management, temporary, and leased employees, worked 452,680 hours at the facility. A total of 25 injury and illness cases involved days away from work (column H). Accordingly, the DAFWII case rate is (25/452,680) _ (200,000) = 11.0.