Despite the installation of ventilation systems and make-up air in most foundries, some job tasks may still require the use of respirators to protect employees from particulates, gases, fumes, vapors and other air contaminants that could affect employee health. With OSHA’s reduced respirable crystalline silica limits now being enforced, foundries using silica sand may need to become more familiar with the requirements of the respiratory protection standard, 29 CFR 1910.134. Not having a written respiratory protection program is the fourth most frequent citation OSHA issues to companies, with 3,381 respiratory protection violations issued in 2017.

This article will review the key components of OSHA’s respiratory protection requirements.

The order of the steps taken to implement a respiratory protection program are important. The first step is to determine if the program is voluntary or required. To make that determination, begin by identifying which contaminants may be in the workplace and conduct indoor air quality sampling to identify the contaminants and their respective concentrations. Safety Data Sheets (SDS) are useful to determine which chemicals should be included in sampling studies. Industrial hygienists can be a significant help to determine the substances to sample and to conduct air quality sampling.

When the lab results arrive, identify which results are over the permissible exposure limit (PEL), and which job tasks have elevated concentrations of contaminants. OSHA has set PELs for about 500 chemicals found in the work place. A PEL is the legal concentration limit OSHA has determined to be safe, for each specific chemical, to which employees may be exposed over an 8-hour workday, without causing negative health effects. If lab results show contaminant concentrations over OSHA’s established PELs, employees must be kept out of the respective work areas, controls must be established to lower the concentration, or a respiratory protection program must be implemented. Air sampling results must typically be shared with employees within 15 days of the company receiving the results, and implementation of a written respiratory protection program should begin immediately and continue until engineering controls or other forms of control are established to lower the exposure concentrations below the PEL.

When the level and type of contaminants are known, it is time to determine if respiratory protection is required (results are over the PEL) or used voluntarily (results are under the PEL). If concentrations are below the PEL and employees choose to voluntarily wear respiratory protection (not required by law), employees must read and sign Appendix D of OSHA’s respiratory protection standard. It is available (in English and Spanish) from OSHA or in the AFS Silica Handbook as Attachment O. (The attachments referenced in this article are available to AFS members on the AFS website at www.afsinc.org/silica, in the Silica Handbook for Small and Medium-Sized Foundries [Silica Handbook], and some of the information is available to all on the OSHA website.)  

If respiratory protection is required, many other requirements come into play. First, respirators must be selected that will protect employees’ health and only NIOSH certified respirators are allowed. There are many types of respirators, from disposable masks, half-masks, full masks, hoods, self-contained breathing apparatus (SCBA), and escape packs. They also come rated as 95 (95%), 99 (99%), or 100 (99.97%) effectiveness for negative-pressure, air-purifying respirators. A respiratory efficiency of 100 is not required and may be more difficult to breathe through. Some respirators filter the air as it is inhaled (air filtering), and others supply air from an airline, a tank, or another fresh air source (air supplying). Equipment vendors can be of significant help in selecting the best respirators for the contaminant(s) found in the work place. They will consider the assigned protection factors to ensure the equipment chosen is adequate for the concentrations in the work place. Another decision to make is whether to use close-fitting or loose-fitting respirators. Close-fitting respirators have a seal that must fit snug to the skin of the face. It requires fit testing initially, annually, and any time equipment or the wearer’s face changes. Men wearing close-fitting respirators must keep a close shaven face, so the seal does not leak, allowing contaminants into the breathing zone. Loose-fitting respirators cover the whole head so they do not require fit testing; however, they are heavier and sometimes visibility is hampered. A couple of advantages of the hooded styles are that they provide effective eye and head protection, and the supplied air can be heated or chilled to provide comfort to the user.

Tips for respirator selection are on the AFS website, in the Silica Handbook, Attachment K. Keep in mind that all components of a respiratory system, even the air line, must be from the same manufacturer. For example, OSHA will likely write a citation if a respirator from one manufacturer is used with cartridges from another manufacturer.

Employees must never be issued respirators, not even disposable face masks, and not even to take a fit test, unless they’ve been given medical clearance to wear a respirator by a physician or other licensed health care professional (PLHCP). So as soon as it is decided which employees will be in a respiratory protection program they can begin by filling out OSHA’s Respirator Medical Evaluation Questionnaire, which is Appendix C of 1910.134 and is also available in AFS’s Silica Handbook as Attachment L. Employees are to fill out the questionnaire confidentially and take it to the occupational medicine facility or submit it online to the screener service of choice. A short list of online screeners can be found in Attachment M of the Silica Handbook.

The written medical evaluation to determine if an employee is fit to wear a respirator is often overlooked. OSHA cited 1910.134(e)(1) over 600 times in 2017. This clause requires employers to provide employees with written medical evaluations to determine their ability to use a respirator prior to fit testing or wearing a respirator at work.

After respiratory equipment has been selected for each required job task, and employees have been given medical clearance, then fit testing may proceed for any users of close-fitting respirators. Fit testing can be done in-house, by a PLHCP, at a local occupational medicine facility, or by a mobile service. Have equipment available in various sizes for employees to try.  If an employee does not have a clean-shaven face, they must shave, or the fit test must be cancelled. If an employee can’t pass the fit test with one size, they can repeat the test in an attempt to pass with another size. If an employee cannot pass the fit test with any of the provided respirators, other brands must be made available to find a respirator that fits better.  The OSHA approved procedure for fit testing can be found in the Silica Handbook, in Attachment P and a Post Respirator Fit Test Record can be found in Attachment Q.  

Training is the next step. A trained and knowledgeable supervisor must oversee the program, prepare a written respiratory protection plan, and be available to workers to answer questions.  For employees who will wear close fitting respirators, it is important to teach them how to conduct positive and negative pressure tests at the start of every shift. These procedures can be found in the Silica Handbook in Attachment R.

All employees must be trained to inspect their respirator for damage, to put the respirator on, adjust the fit, and take the respirator off. Employees must be taught how to clean their equipment, how to properly dry and store it (don’t hang it from the straps), and when it is time to change out filters or cartridges. Training must include which contaminants the respirator will protect them from, and the highest concentration the respirator can handle. Employees must be taught the signs of respirator failure and the symptoms of over-exposure to the chemicals in their work area. If respirators are shared by two or more people, they must be disassembled and sterilized between uses.  

Click here to see this story as it appears in the November 2018 issue of Modern Casting