Pouring, drossing, moldmaking, abrasive blasting, chipping, grinding, and welding are all common processes in metalcasting operations that may result in exposure to airborne contaminants and agents, like metal fumes, silica dust, formaldehyde, and isocyanates. These basic operations account for the fact that metalcasting plants use respirators at a rate six times greater than other industries, according to a 2001 Bureau of Labor Statistics Survey of Respirator Use and Practices.
Despite the wide use of respirators in these operations however, the study found 48% of metalcasting operations had three or more indicators of a potentially inadequate respiratory protection program, as measured against OSHA's respirator program requirements.
One of the most common of theses inadequacies discovered by the study was the lack of a proper maintenance program.
A respirator maintenance program puts a person or people in charge of performing cleaning, inspecting the condition, conducting repairs and ordering replacements. Each time maintenance is performed it should be logged by the person conducting maintenance. Following here is a maintenance policy that you can feel confident about implementing at your workplace.
Respirator cleaning and disinfecting procedures
Use the following procedures when cleaning and disinfecting respirators:
• Disassemble the respirator, removing any filters, canisters or cartridges;
• Wash the facepiece and associated parts in a mild detergent with warm water — except the cartridges, which should never be allowed to get wet. Do not clean or wash with organic solvents, etc;
• Rinse completely in clean, warm water;
• Wipe the respirator lightly with disinfectant wipes (70% isopropyl alcohol) to kill germs, as needed;
• Thoroughly air-dry in a clean area;
• Reassemble the respirator and replace any defective parts;
• Place in a clean, dry plastic bag or other airtight container.
Respirators are to be properly maintained for proper function and adequate protection at all times. Maintenance involves thorough visual inspection for cleanliness and defects. If the person conducting maintenance notices deteriorated parts, those parts must be replaced prior to use.
However, note this important detail: do not replace components or make repairs beyond the steps recommended by the manufacturer.
It is critical for employees to inspect respirators before and after each use. The following checklist should be used when inspecting respirators:
• Facepiece: check for cracks, tears, holes, facemask distortion, cracked or loose lenses/faceshield, etc;
• Headstraps: breaks, tears, or bent or broken buckles;
• Valves: residue or dirt, cracks or tears, valves stuck or folded open;
• Filters/cartridges: NIOSH approval designation/label clearly visible, gaskets, cracks or dents in housing, proper cartridge for hazard;
• PAPRs: hose condition, gaskets, motor function, battery charge and condition;
• Air supply systems: breathing-air quality/grade, condition of supply hoses, hose connections, settings on regulators, and valves.
All respirator maintenance should be conducted in a designated area that is free of respiratory hazards. Employees should be instructed they are allowed to leave their work if they need to conduct respirator maintenance in the following situations to wash their face and/or facepiece to prevent eye or skin irritation, to replace the filter cartridge or canister if vapor odors or chemical breakthrough or leakage is detected, or if any other damage to the respirator or its components is detected.
Filter-cartridge change schedules
Particulate filter cartridges: Employees wearing respirators with High-Efficiency Particulate Air (HEPA) filters must change the cartridges when they first begin to experience increased breathing resistance while wearing their masks, or at least annually.
It is important to store respirators in a clean, dry area and in accordance with the manufacturer's recommendations. Each employee must clean and inspect his/her respirator and store the respirator in a clean plastic bag.
Defective respirators or parts shall be taken out of service immediately. If, during an inspection, an employee discovers a defect, he/she is to notify their supervisor immediately. Supervisors will decide which of the following actions to take next:
• Temporarily remove the respirator from service until it can be repaired;
• Perform a simple fix on the spot, such as replacing a headstrap;
• Dispose of the respirator due to an irreparable problem or defect.
When a respirator is taken out of service for an extended period of time, the respirator should be tagged “out of service,” and the employee must be given a replacement of the same make, model, and size.
Michael Rich is a safety writer and researcher for Safety Services Company, a supplier of safety training materials and compliance products in North America. If you would like more information about how to create a respirator program, contact him by e-mail. Learn more at www.safetyservicescompany.com.