Success story-aep Welding Study/policy Revision at AEP. Louis O. Hosek, Ph.D.
Welding Study Overview From early 2007 until April 2009, a study to identify exposures to the metals in welding fumes was conducted by Corporate IH. The study used 555 personal air samples taken throughout AEP on many different types of jobs. The study included both AEP employees and contractor employees.
Welding Study Overview The study was undertaken to determine the level of exposure from the various metal fumes and make recommendations based on the information. Each of the metals that could be present in the welding process has potential health effects.
Welding Study Overview The primary type of welding performed was Shielded Metal Arc Welding (SMAW), commonly referred to as stick welding Other common welding procedures performed were: -- MIG (Gas Metal Arc Welding) -- TIG (Gas Tungsten Arc Welding) -- Arc Gouging (Air Carbon Arc Cutting)
Welding Study Overview The metals that are measured in the welding fume profile are: - Aluminum - Beryllium - Cadmium - Chromium (total) - Cobalt - Copper - Iron - Lead - Manganese - Molybdenum - Nickel - Titanium - Zinc - Vanadium
Welding Study Overview Although the health effects differ by the metal, amount of fume exposure, etc., some health concerns from welding fumes include: - Carcinogenic Effects - Acute and Chronic Pulmonary Changes - Asthma - Nervous System Effects - Metal Fume Fever
Welding Study Overview Welding can also expose the worker to many other hazardous substances, including: -- Fluorine compounds -- Fluxes -- Carbon monoxide -- Ozone -- Nitrogen oxides -- Silica -- Shielding gases -- Ionizing, IR and UV radiation -- Compounds from cleaners and coatings decomposed by heat, including Phosgene and Acrolein These were not monitored during the study.
Welding Study Overview The highlights of the study include: -- 100% of a PEL or TLV was exceeded 29 times in the study. -- 50% up to 100% of a PEL or TLV was exceeded 52 times. This was noted due to the fact that under slightly longer actual work exposure times or other factors, these could approach the PEL or TLV.
Welding Study Overview Aluminum, Chromium, Copper, Iron, Manganese, Nickel, Titanium and Zinc were found above detectable levels in greater than 75% of the samples. -- Beryllium was found above detectable levels in only 6 (or 1.1%) of samples. -- Cadmium was found above detectable levels in only 12 (or 2.2%) of samples.
Welding Study Overview The metal of most concern from the study is Manganese (Mn): -- Found above detectable levels in 97.1% of all samples, from all types of welding. -- The TLV was exceeded 19 times. The PEL is a ceiling limit, was not measured. -- The 50% to 100% of TLV was exceeded 32 times.
Welding Study Overview Manganese exposure is a hot issue in the legal community. Numerous cases involving Manganese exposure have been tried, with varying results. These lawsuits have been directed at manufacturers. The next step could be large users of Mn containing welding materials. The primary health concern is Manganism, a Parkinson s-like disease which affects the nervous system.
Existing Policy Change Welding, Cutting, Brazing Policy changed Now requires the use of RP unless airborne level is known An NEA can exempt certain jobs 2-hour exemption TIG not included
Respiratory Protection The primary change in the policy will be the requirement of using respirators for welding processes that are not exempted or do not have an established job-specific NEA. Welding processes that will require a minimum of a half-face respirator with P- 100 filters (if no NEA is established) include:
Respiratory Protection Shielded Metal Arc Welding (SMAW) Gas Metal Arc Welding (GMAW or MIG) Plasma Arc Welding (PAW) Plasma Arc Cutting (PAC) Oxyfuel Gas Cutting (OFC or torch cutting) Grinding and cutting on coated metals
Respiratory Protection Respiratory protection greater than a half face respirator is required for Arc Gouging (CAC-A, air arcing). All persons wearing respirators must meet all of the requirements of the AEP Respiratory Program and OSHA standards.
Exempted Practices Welding practices that do not require the use of respiratory protection include: Submerged Arc Welding (SAW or SubArc) Robotic Welding Stud Welding (SW) Spot Welding
Exempted Practices Brazing Exothermic Welding Soldering Grinding on bare metals
Exempted Practices Also exempted is Tungsten Inert Gas (GTAW or TIG) welding. This is a systemwide NEA that will be reviewed annually. Shop welding is exempted if it has been demonstrated the ventilation is adequate. The exempted practices generally do not generate large amounts of metal fume or the worker is not close to the fume generation.
Exempted Practices An exemption has been added for jobs where the entire length of the welding task (not just the fume generation) is less than 2 hours. The following criteria must be met: - Arc Gouging is not a part of the task. - No additional metal fume exposure is permitted during the same workday without respiratory protection.
Exempted Practices - Does not involve metals/materials regulated under other OSHA standards or AEP policies. - Limited to minor maintenance tasks. - Ventilation requirements still apply. If task exceeds the 2 hour timeframe or there are any questions regarding exemptions, respiratory protection should be used.
Exposure Limits The exposure limit for Manganese (Mn) in our policy will be 0.2 mg/m3 as an 8 hour TWA. This is the 2010 ACGIH TLV for Mn. The OSHA PEL is currently a ceiling limit of 5.0 mg/m3 for a 15 minute sample. This limit was established in 1968, medical research indicates that there may be health concerns at much lower levels than the PEL.
Exposure Limits 0.2 mg/m3 is the generally accepted exposure limit for Mn throughout industry. All other metal fumes will continue to be evaluated at their current OSHA PELs. The AEP welding fume profile analyzes 14 different metals.
Conclusions Primary changes in the policy include: - Establishing the exposure limit of Manganese (Mn) at 0.2 mg/m3 as an 8 hour Time Weighted Average (TWA) (Section 6.0). - Requiring the use of respiratory protection and ventilation for jobs that are not exempted and where a Negative Exposure Assessment (NEA) has not been established (Section 11.0 for Respiratory Protection, Section 7.0 for Engineering and Administrative Controls).
Conclusions The changes to the policy are intended to reduce the potential health effects associated with metal fume exposures. There are other hazards beyond metal fumes which may also be reduced with proper respiratory protection and engineering controls.
1 st Step-The Study Hypothesis-Based on earlier HexChrome work First take of study completed with 225 samples. Report written for internal review. Leaked out.
Push Back Normal resistance Another Corporate Rule Cost Will lose contractors Can t get any work done Too many rules already Been doing this way forever why now? Will drive workers to workers comp. Machismo Etc.
More Samples Let s do more samples and get a bigger database. Another 300 samples. Same breakdown of sample outcomes. Completed write up.
Determine Biggest Oppostion Old Football Adage Run at the person giving you the biggest problem You can control/defuse the opposition Formed a committee with them
Ad Hoc Welding Committee 2 corporate His 4 people from opposition Group Chaired by Regional VP Generation Educated him on the study/conclusions Series of meetings Agreement
Outcome Let them have some of their points. Held firm on the important technical issues. One year Phase-in period Negative Exposure Assessments (NEA)
Senior Executive Committee Sr. VP-Opposition group Sr. VP of EHS VP of Safety and Health Rep. from Opposition team Corp. IH member
Presented Final Agreement to Sr. Executive Team Got approval/buy in from Sr. Exec s. Endorsed Policy Change Media Presentations Training programs ready Met with contractors
Policy Change Effective 10-31-11 Good acceptance Why? Team input Disarmed opponents Executive stamp of approval Doing it for Occupational Health reasons Reasonableness