Presentation on theme: "1 WMIHS Silica and Manganese March 3, 2015 James R. Strobridge, CIH."— Presentation transcript:
1 WMIHS Silica and Manganese March 3, 2015 James R. Strobridge, CIH
2 Silica Federal OSHA new proposed crystalline silica standard will lower the PELs for quartz, cristobalite and tridymite. The new federal PELs currently being considered include: - 0.1 mg/m3 - 0.05 mg/m3 - 0.025 mg.m3
Silica Don’t look for any new silica PELs anytime soon. Per Martha Yoder when she spoke to the WMIHS last year. 3
4 Silica The current occupational exposure limits (OELs) include the following: –Federal OSHA PEL - 10/% silica + 2 formula –MIOSHA PELs - 0.1 mg/m3 for quartz and 0.05 mg/m3 for cristobalite and tridymite –NIOSH REL - 0.05 mg/m3 for quartz –ACGIH TLVs - 0.025 mg/m3 for quartz, cristobalite and tridymite
5 Silica OSHA needs to address the PEL issue because the current silica PEL is out of date and employees are not protected. Employers are not protected from Work Comp suites regarding silicosis, scleroderma and other silica related diseases if they are using the OSHA or MIOSHA PELs
Silica Scleroderma Workers Comp Case I was the IH brought in to testify that the air sampling results met the PELs at the time the employee was working. The employer’s case was dead on arrival because they could not show that they were meeting the more stringent OELs from NIOSH and ACGIH. 6
Silica The following are 2014 foundry operations air sampling results for silica: –Auditing: 0.050, 0.082, 0.048, 0.16 mg/m 3 –Finishing: 0.030 mg/m 3 –Didion Op: 0.12, 0.11 mg/m 3 –Process Tech: 0.044 mg/m 3 –Shakeout: 0.033, 0.029 mg/m 3 –Sand Control Op: 0.053, 0.041 mg/m 3 7
Silica Note: Foundry operations are extremely hard on the equipment. Can have acceptable exposures and 3 months later no deal because of the wear and tear on the equipment Equipment requires frequent PM and repairs. Solutions –Ventilation and Engineering controls –PPE, respiratory protection 8
9 Manganese The concerns are the potential neurological effects associated with exposure to manganese fumes. Manganese is an essential nutrient. A healthy person with normal liver and kidney function can excrete excess dietary manganese.
10 Manganese Inhaled manganese is of concern because it bypasses the body’s normal defense mechanisms. This can lead to manganese accumulation and adverse health effects including damage to the lungs, liver, kidney, central nervous system, and fertility problems in males.
11 Manganese Prolonged exposure to high manganese concentrations (>1 mg/m3) in air have been linked to a Parkinson type syndrome As a result, relying on the MIOSHA PEL of 1.0 mg/m3 may not be providing adequate protection. However, the ACGIH TLV of 0.2 mg/m3 will provide better protection.
12 Manganese Note: recent studies indicate neurological and neurobehavioral problems may occur even when workers are exposed to low levels (<0.2 mg/m3) of manganese fumes. The effects include changes in mood, short-term memory, altered reaction time, and reduced hand-eye coordination. Affected workers frequently show abnormal accumulations of manganese in a region of the brain that plays an important role in movement regulation.
Manganese Current OELs for Manganese include: - MIOSHA PEL = 1 mg/m3(TWA) - NIOSH REL = 1 mg/m3(TWA) - OSHA PEL = 5 mg/m3 (which is a ceiling) - ACGIH TLV = 0.2 mg/m3 (TWA) - New proposed ACGIH TLV is 0.02 mg/m3 (TWA) Current understanding indicates that the TLV should be used for evaluating workplace exposures. 13
Manganese As with silica, relying on the OSHA and MIOSHA PELs will not provide any type of protection for the employer during a Workers Comp case due to the fact that there is a more stringent OEL that is recognized by health and safety experts as well as the occupational medical profession. 14
Manganese The following are a few 2014 MIG welding air sampling results for total weld fume (WF), iron oxide (IO) and manganese (MAN): –*WF: 5.1 mg/m 3 IO: 2.3 mg/m 3 MAN: 0.37 mg/m 3 –*WF: 5.4 mg/m 3 IO: 2.4 mg/m 3 MAN: 0.36 mg/m 3 –*WF: 8.7 mg/m 3 IO: 3.3 mg/m 3 MAN: 0.68 mg/m 3 –**WF: 9.3 mg/m 3 IO: 5.3 mg/m 3 MAN: 0.31 mg/m 3 –***WF: 25 mg/m 3 IO: 6.2 mg/m 3 MAN: 0.26 mg/m 3 –* using bib on welders helmet –** no bib on welders helmet –*** Plasma Torch Op 15
Manganese I have not encountered these types of exposure levels with TIG Welders MIG welding and plasma torch operations will produce significant welding contaminants without the proper engineering controls. The amount of welding contaminants is also directly related to how much weld is being laid down. (Tack weld versus several inches of weld) 16
Manganese Solutions include the use of ventilation and engineering controls, PPE and respiratory protection or switching to a different welding process. Ventilation and engineering controls work well when the operations are confined to a welding booth, a single fixture or welding table. However, what about when the welding operations involve 40 to 60 foot steel frames? RV and trucking manufacturers. 17
Manganese Smoke Eater weld guns PPE and respiratory protection can include: –Bib on helmet –Using respirator under the welding helmet –Air supplied welding helmet If possible, switch to a TIG welding operation or automated operation. 18