Frameworks for Protecting Workers and the Public from Inhalation Hazards (2022) / Chapter Skim
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3 Respiratory Protection in the Workplace
3 Respiratory Protection in the Workplace
Pages 127-206
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From page 127... ...
but who may face occupational exposures on a regular or intermittent/episodic basis; they also include workers who are not usually exposed to inhalation hazards in the course of their job duties but may be exposed in exceptional circumstances (e.g., epidemics, wildfires and other extreme pollution events)
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From page 128... ...
The committee acknowledges that this is not an exhaustive analysis of worker groups and that there are a multitude of work settings in which workers do not receive sufficient protection from inhalation hazards, both recognized and unrecognized. UNMET RESPIRATORY PROTECTION NEEDS IN THE WORKPLACE Unmet needs for respiratory protection result when workers are exposed to inhalation hazards but either do not have access to respiratory protection or use such devices outside of an RPP, resulting in reduced protection or even health risks from the device itself.
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From page 129... ...
The traditional employer–employee relationship that was common 50 years ago is far less frequent today, and occupational safety and health is becoming more complex with the transition away from long-term, fixed-site employment relationships. Individuals may work for many different organizations throughout their lives, with a growing number involved in a nontraditional employer–employee relationship, such as independent contracting or temporary work, as well as what is often called the sharing or gig economy (Weil, 2014)
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. In addition to the gaps in worker protections created by the changing nature of work and employer–employee relationships in the United States, further challenges stem from workplace exposures to inhalation hazards that arise only in the context of public health and environmental emergencies, such as infectious disease epidemics and wildfires.
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From page 131... ...
Part of the challenge stems from the fact that, with the exception of a few chemical-specific standards, OSHA does not specify industries or worker groups that are subject to its Respiratory Protection Standard. Rather, this determination must be made at the workplace level based on a hazard assessment, with consideration of whether any potential inhalation hazards can be adequately mitigated through other controls.
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The scope of unprotected workers could be estimated by calculating the number of workers in industries who are exposed to inhalation hazards but not covered by an RPP because of noncompliance with or exclusion from OSHA standards, as well as those working in locations that usually BOX 3-1 Data Sources for Estimating the Scope of Unprotected Workers Exposed to Inhalation Hazards The following sources of data on workforce statistics, hazardous exposures, occupational disease rates, and respiratory protection programs could inform the scope of the problem related to unprotected workers exposed to inhalation hazards. • Workforce numbers and industry and occupational data from the Bureau of Labor Statistics (BLS, 2020)
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From page 133... ...
. Therefore, unless a formal complaint is made or the hazard is already known to OSHA, most workplaces with inhalation hazards are likely to avoid citation.
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From page 134... ...
Given these limitations, any estimation of the number of workers not covered by RPPs who are potentially exposed to inhalation hazards at their workplaces will necessarily be a gross undercount and incomplete. The ability to generate a reasonable estimate would require NIOSH, in conjunction with OSHA, the Mine Safety and Health Administration (MSHA)
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From page 135... ...
Conclusion 3-2: Regulatory and public health agencies do not collect adequate data for assessing and evaluating the risk posed by hazards in the workplace and compliance with respiratory protection regula tions. This inadequate data collection impedes understanding of the scope of workers exposed to inhalation hazards but not covered by RPPs.
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From page 136... ...
involve potential exposures to inhalation hazards that cannot be mitigated through engineering controls or other mechanisms higher on the hierarchy of controls. In such cases, it may be necessary to use respirators in the workplace in the context of an RPP to prevent specific illnesses and exacerbation of chronic illnesses caused by breathing contaminated air.
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From page 137... ...
, who examined fatalities associated with the use of respiratory protection in industrial settings between 1990 and 2012. The authors note a reduction in fatality rates during that time period that appears to be associated with the 1998 publication of OSHA's revised Respiratory Protection Standard, which included new language designed to ensure that employers would have sufficient guidance to support the selection and maintenance of respiratory protective devices.
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. More recently, a study of California hospitals during the 2009–2010 H1N1 influenza pandemic showed that although health care workers reported knowing that they should wear N95 filtering facepiece respirators (FFRs)
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. The Respiratory Protection Standard is consistently among the top 10 most frequently cited OSHA standards (OSHA, 2021h)
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NOTE: APF = assigned protection factor; RPP = respiratory protection program. While challenges related to latency of outcomes and confounding factors limit the availability of direct evidence on the effectiveness of RPPs, it can be inferred from indirect evidence in the form of exposure reduction studies and dose-response relationships that RPPs, when implemented appropriately and enforced, protect workers from inhalation hazards.
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From page 141... ...
This section reviews programs regulated by other government agencies, as well as other respiratory protection models -- including voluntary programs -- that could be implemented when full RPPs are not required. Other Program Types Other Federal and Nonfederal Programs The requirements laid out in OSHA's Respiratory Protection Standard are widely accepted and referenced by other entities with identified inhalation hazards in their workplaces.
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From page 142... ...
Alternative Approaches in the Context of the COVID-19 Pandemic SARS-CoV-2, which was recognized belatedly as an airborne inhalation hazard, presents extensive challenges for protecting workers and has altered the landscape for regulation of worker respiratory protection. On January 21, 2021, the Biden administration issued an executive order directing OSHA to take action to reduce the risk to workers of contracting COVID-19 at their workplaces (Executive Office of the President, 2021)
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From page 143... ...
. c For additional information about the Respiratory Protection Standard's requirements, see NIOSH/ OSHA's "Hospital Respiratory Protection Program Toolkit Resources for Respirator Program Administrators" at www.osha.gov/sites/default/files/publications/OSHA3767.pdf (accessed September 27, 2021)
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From page 144... ...
. Voluntary Use of Respiratory Protection in the Workplace This section addresses cases in which an employer chooses to provide employees with respiratory protective devices or to allow employees to bring their own devices when their use is not covered or required under federal or state regulations.
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, employers are not required to pay for or provide these respirators to employees, but are required to ensure that employees are familiar with the training outlined in Appendix D of the OSHA Respiratory Protection Standard. Respirators used voluntarily include those that are not filtering facepiece devices and those that are (see Figure 3-2)
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146 PROTECTING WORKERS AND PUBLIC FROM INHALATION HAZARDS FIGURE 3-2 OSHA requirements related to voluntary use of respirators in the workplace in the absence of a formal respiratory protection program.
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Fit testing is not a requirement for medical masks used in the workplace since the devices are not intended to provide a tight seal to the face of the wearer. However, workers using such masks voluntarily should have adequate instruction on • how to don the device properly, including the orientation on the face; • the need to either properly dispose of the medical mask or clean it after use; • the need to disinfect the mask if the hazard is an infectious agent; • a proper method for safely storing the device if it will be reused; and • a requirement that it not have exhalation valves if the hazard is an infectious agent.
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From page 148... ...
However, it may be anticipated that many workers will wear barrier face coverings in the workplace voluntarily even after indoor mask mandates and individual employer policies requiring their use have been lifted, although some may prefer respirators over barrier face coverings once supply issues have been resolved. Summary and Synthesis Circumstances in which respiratory protection might be used by workers outside of an OSHA-mandated RPP include voluntary use of respiratory protective devices on the part of employees and an array of situations in which agencies other than OSHA may call for RPPs, although OSHA regulations remain the starting point in such situations.
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From page 149... ...
Conclusion 3-4: For employers and employees unfamiliar with tra ditional RPPs, adherence to and conformance with requirements for respiratory protective devices may seem complicated and confusing. Lack of familiarity with hazard assessment may contribute to under recognition of inhalation hazards, and the large number of products available adds to the confusion regarding device selection.
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From page 150... ...
For example, many agricultural workers are hired as temporary or day laborers, and such workers may on occasion be exposed to smoke if required to work in proximity to wildfires. Moreover, some worker groups discussed in this section who may remain close to a hazard even when not working, including wildland firefighters and disaster workers, are exposed to inhalation hazards on an ongoing basis in the course of their work and face unique challenges beyond these two gap areas.
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From page 151... ...
. As discussed below, these strenuous working conditions have implications for the kinds of respiratory protective devices that would be suitable for wildland firefighters.
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From page 152... ...
TABLE 3-2 Wildland Firefighters' Job Tasks Categorized into Four Groups Based on Activity Level and Percentage 152 of Total Person-Task Observations in the Data Set in the Wildland Firefighter Heat Related Illness Study, Western United States, 2013–2016 SEDENTARY LIGHT PHYSICAL MODERATE HIGH PHYSICAL ACTIVITY % ACTIVITY % PHYSICAL ACTIVITY % ACTIVITY % ICP Stationary 1.7 Handline Direct Pump 0.1 Mop Up 5.1 Handline Direct Scratch 0.7 ICP Other 0.2 Handline Indirect Pump 0.02 Cold Trailing 0.6 Handline Direct Sawyer 0.5 Briefing 6.7 Handline Indirect Dozer 0.02 Improving Direct Line 0.2 Handline Direct 0.6 Boss Swamper Driving 6.9 Holding Direct Line 1.3 Improving Indirect Line 1.1 Handline Direct Engine 0.1 Lunch Break 3.6 Holding Indirect Line 0.2 Felling Sawyer 0.6 Handline Direct Squad 0.1 Leader Rest Break 3.3 Holding Firefighter 0.7 Felling Swamper 0.6 Handline Direct Fire- 0.2 fighter Operational Break 19.5 Holding Squad Leader 0.2 Working with Aviation 0.1 Handline Indirect 0.4 Scratch Staging 0.9 Holding Engine 0.1 Scouting Hazard Trees 0.7 Handline Indirect 0.6 Sawyer
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Other 0.5 Suppression Holder 0.8 Grid the Black 1.5 Handline Indirect 1.2 Swamper Total 43.2 Engine Pump Operator 0.2 Grid the Green 0.6 Handline Indirect 0.3 Squad Leader Holding Pump 0.1 Tool Up/Tool Down 8 Handline Indirect 0.2 Firefighter RX Holder 0.2 Total 19 Live Preparation 0.5 Refurb Tools 3.3 Initial Attack 0.1 Structure Protection 1.1 RX Lighter 0.2 Compound Work 1.4 Suppression Lighter 0.8 Total 9.4 Physical Training 1.3 Project Saw 0.6 Project Stacking 0.7 Hiking 19.2 Medical 0.1 Total 28.4 SOURCE: Reproduced from Occupational and Environmental Medicine, M.R.
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From page 154... ...
studied wildland fire exposure in the Midwestern United States during prescribed burns, finding that the overall exposure levels were higher than those reported in studies of wildland firefighters in the western and southeastern areas of the United States, providing evidence for the role of fuel models and operational tasks in the smoke exposure of wildland firefighters. The authors also reported that no value was over the 8-hour OSHA PEL (Wu et al., 2021)
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From page 155... ...
. These projections suggest the need for more long-term studies to assess the health risks of smoke exposure for wildland firefighters.
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From page 156... ...
concentrations measured on wildland firefighters. These graphs show different levels of exposure to PM and CO captured in a review of relevant studies, and the difference between the recommended operational exposure limits (OELs)
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Relative risk increases for lung cancer and CVD among wildland firefighters as the daily dose of particulate matter (PM) increases.
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From page 158... ...
, but may be challenging to achieve in a workforce characterized by a large number of seasonal and volunteer workers. Limited authoritative guidance is available on the use of respiratory protection by wildland firefighters and their agencies/departments for such hazards as wildfire smoke and infectious respiratory diseases.
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From page 159... ...
. Thus, wildland firefighters face a near total absence of established federal guidance on the use of respiratory protective devices as respiratory protection from wildfire smoke.
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From page 160... ...
. The respiratory protection needs of agricultural workers exposed to dusts, molds, and chemicals from farm work are likely to differ in important ways from those of workers incidentally exposed to wildfire smoke.
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From page 161... ...
. Increased knowledge and understanding of inhalation hazards is an important factor in promoting the use of respiratory protection among agricultural workers, particularly in cases in which hazards emanate from beyond the immediate work processes and procedures (e.g., wildfire smoke, aerosol transmissible diseases)
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From page 162... ...
NIOSH has developed guidance on the potential role of respiratory protective devices in controlling exposure to wildfire smoke as part of an RPP (NIOSH, 2021b) ; however, this guidance does not focus specifically on agricultural workers.
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From page 163... ...
Among the guidance available to agricultural workers, that provided to support the use of respiratory protection from standard to application in the field appears to be most complete for pesticide exposures. Construction Workers Description of the Workforce, Work Environment, and Work Characteristics Construction firms are overwhelmingly small employers -- 90 percent employ fewer than 20 people -- with limited resources for proper PPE or training for their workers.
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. Exposure and Health Impact Data Inhalation hazards are common in the construction sector.
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, construction was the second most commonly cited industry. Several federal agencies, labor unions, and professional associations provide guidance for the construction workforce on a variety of inhalation hazards, including SARS-CoV-2.
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. In addition to the standing day labor workforce, researchers have recently turned their attention to the role played by day laborers as "second responders" in the context of disaster response and recovery (discussed further in the section below on disaster response and recovery workers)
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, may be applicable, these workers are unlikely to be employed in a situation in which an RPP is established. The committee identified no other guidance on other inhalation hazards addressing use of respiratory protection by day laborers or targeted employers of these workers.
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From page 168... ...
. Home care workers (including home health workers and personal care attendants)
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, have always been vulnerable to many health care safety hazards, including inhalation hazards (Nasol and Francisco-Menchavez, 2021)
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. Care professionals who work in assisted living facilities experience similar safety problems, including inadequate protection against inhalation hazards.
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From page 171... ...
. The vast majority of health care workers in the United States, including those who work in states with OSHA-approved State Plans that do not provide this protection or those in states with federal OSHA programs, are not covered by a specific, formal, permanent aerosol transmissible disease standard.
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From page 172... ...
172 100% 80% 60% Did not wear 40% any respirators or masks Percent of users 20% Used a surgical mask 0% g in ics ne s s er y s din ing vir ot idi nt nt las er es Used a n er a i r ila c ta , u rg lln ou st rib tib am fe ke os ei respirator p ini d an nt l ste sin o lik om m ze d pe i m ctr ,c , ad oli ze d ica ld ls le za s s li ze m e a e ,e en ug gs ro so oli he lev gic u dr d ru Ae ro s C ur ok Infl Ae ro gh S m s tic s tic Ae Hi ls pla pla g ica eo eo S ur tin tin An An Hazard FIGURE 3-5 Respiratory protection practices for health care workers exposed to airborne hazards. This bar chart shows how the use of respirators and surgical masks and the use of no device vary by respondent across exposures to different types of hazards, indicating that use of respiratory protective devices varies for the same hazard and that worker safety may be at risk.
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From page 173... ...
. Limited authoritative guidance is available that directly focuses on workers in long-term care and assisted living facilities with respect to the use of respiratory protective devices for COVID-19.
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From page 174... ...
Workers at Increased Risk of Exposure to Infectious Diseases from Interaction with the Public or Other Workers During Epidemics and Pandemics Description of the Workforce, Work Environment, and Work Characteristics The COVID-19 pandemic and the 2009 H1N1 pandemic have demonstrated the importance of respiratory aerosol transmission to a wide range of public-facing workers, including teachers, wait staff, day care providers, public transportation workers, janitors, and workers in correctional facilities and homeless shelters, among many others. Those working in close proximity to others, such as in manufacturing and food processing, also have experienced high rates of worksite transmission.
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From page 175... ...
. Despite limitations of the available data, some data are available on the differential impacts of COVID-19 by industry/sector: • Early data from six Asian countries suggested excess infections among health care workers, drivers and transport workers, services and sales workers, cleaning and domestic workers, public safety workers, and religious professionals, with increases among different groups appearing at different times (Lan et al., 2020)
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From page 176... ...
. Characteristics of work and the workforce that increase risk and vulnerability include exposure to infectious aerosols among those not able to work remotely; lack of appropriate occupational safety and health protections, including training; densely populated, poorly ventilated, or enclosed work spaces; prolonged face-to-face or physical contact where social distancing is not practiced; demographic characteristics; comorbidities; and coexposures (Carlsten et al., 2021)
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From page 177... ...
. Workers and volunteers in homeless shelters have long been aware of respiratory transmission of tuberculosis and other infectious diseases.
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From page 178... ...
TABLE 3-3 Characteristics of Workers in Front-Line Industries 178 TRUCKING, GROCERY, WARE ALL CONVE- HOUSE, CHILD FRONTLINE NIENCE, AND BUILDING CARE AND ALL INDUS- AND DRUG PUBLIC POSTAL CLEANING HEALTH SOCIAL WORKERS TRIES STORES TRANSIT SERVICE SERVICES CARE SERVICES All Workers 152,600,169 31,673,098 6,817,890 804,495 3,128,922 1,484,993 16,103,877 3,332,921 (16+) Female 47.4% 64.4% 50.5% 29.1% 22.7% 53.2% 76.8% 85.2% Full/Part-Time Full-Time 78.6% 73.3% 63.7% 81.0% 90.5% 62.6% 79.8% 67.4% Part-Time 21.4% 24.7% 36.3% 19.0% 9.5% 37.4% 20.2% 32.6% Race/Ethnicity White 63.5% 58.8% 59.5% 54.7% 56.4% 43.4% 61.1% 55.8% Black 11.9% 17.0% 14.2% 26.0% 18.2% 12.6% 17.5% 19.3% Hispanic 16.8% 16.3% 18.5% 14.0% 20.0% 40.2% 12.1% 18.0% AAPI 6.6% 6.7% 6.6% 4.1% 4.2% 2.4% 8.0% 5.3% Other 1.2% 1.2% 1.3% 1.2% 1.1% 1.3% 1.2% 1.5% Foreign Born 17.1% 17.3% 15.7% 15.2% 17.9% 38.2% 16.2% 17.0% Education Level
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From page 179... ...
LTHS 9.3% 8.5% 13.0% 6.9% 12.7% 26.5% 4.3% 7.9% HS 24.5% 25.8% 36.0% 38.1% 42.6% 38.5% 17.2% 21.7% Some 32.0% 36.3% 35.2% 39.4% 34.2% 26.0% 38.2% 34.7% College College 21.6% 18.1% 11.9% 11.4% 8.7% 7.4% 22.8% 22.9% Advanced 12.6% 11.4% 4.0% 4.1% 1.8% 1.5% 17.5% 12.8% Age 50+ 33.1% 33.9% 27.4% 46.7% 40.2% 35.6% 34.6% 34.4% Home 65.3% 63.6% 59.6% 68.2% 65.5% 50.0% 66.7% 60.1% Ownership Public Transit 5.1% 4.8% 4.5% 9.0% 2.4% 7.8% 4.6% 6.8% Commute to Work Compensation and Benefits Below 6.7% 7.2% 10.0% 4.5% 4.7% 15.9% 5.2% 10.8% Poverty Line <200% 20.6% 23.0% 30.1% 16.0% 19.2% 42.4% 17.8% 30.0% Poverty Line No Health 11.0% 9.9% 12.1% 5.8% 14.8% 29.1% 6.3% 10.4% Insurance 179 continued
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TABLE 3-3 Continued 180 TRUCKING, GROCERY, WARE ALL CONVE- HOUSE, CHILD FRONTLINE NIENCE, AND BUILDING CARE AND ALL INDUS- AND DRUG PUBLIC POSTAL CLEANING HEALTH SOCIAL WORKERS TRIES STORES TRANSIT SERVICE SERVICES CARE SERVICES Family Responsibilities Child in 35.8% 35.9% 33.9% 32.6% 33.3% 38.8% 36.9% 36.0% home Senior 14.8% 16.0% 16.8% 18.4% 14.9% 15.5% 15.3% 18.5% (age 65+) in home SOURCE: CEPR's Analysis of American Community Survey, 2014-2018 5-Year Estimates.
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Here again, the primary response required is adequate enforcement of existing Department of Labor protections. Failure to protect essential workers, including health care workers, marked the first year of the pandemic.
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From page 182... ...
. CDC maintains several occupation-specific guidance documents, including new or updated guidance for restaurant and bar operators, in-home social service providers, public transportation operators, and airline crews, which include links to general guidance on types of respiratory protective devices and their use (CDC, 2021b,g,k,l)
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From page 183... ...
Day laborers have also been engaged in response and recovery efforts for many disasters over the past two decades, including • the attacks on the World Trade Center in 2001 (EHS Today, 2002) ; • Hurricane Katrina in 2005 (Delp et al., 2009; Fletcher et al., 2006)
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From page 184... ...
It is critical to delineate clearly when the rescue phase has concluded and the disaster has shifted to a more controlled recovery phase, during which the hazards may still be present but the pace can be slowed and the work shifts reduced, allowing responders to catch up on sleep and meals, which also reduces their risk; the key is to recognize that the longer the rescue phase continues, the greater is the risk. Yet, the shift from rescue to recovery operations is not always apparent, as was the case during the World Trade Center response, in which the rescue phase was reportedly extended through June 2002 for the entire 9 months of debris removal operations (Newman, 2013)
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From page 185... ...
. And as discussed at length above, in the case of wildfires, exposure to wildfire smoke has been associated with respiratory symptoms, as was the case, for example, with day laborers and domestic workers who reported breathing difficulties following the Woolsey fire (IDEPSCA, 2020)
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From page 186... ...
, which are similar to OSHA's. Construction workers Inadequate use of respiratory protection by construction workers at the World Trade Center is a well-documented problem.
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. Day laborers Despite the increasingly frequent role of day laborers in disaster response and recovery efforts, employers often fail to provide them with PPE or training, let alone other aspects of an effective RPP (e.g., fit testing, medical clearance)
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From page 188... ...
has developed mold remediation guidance oriented toward disaster recovery volunteers and essential workers, providing them with detailed information about the selection and use of respiratory protection and other types of PPE. Summary and Synthesis This section has considered multiple worker groups that are potentially exposed to inhalation hazards in the workplace.
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From page 189... ...
Unique challenges are faced by some of these workers, such as day laborers, who represent a fluid group that may be hired because the jobs may involve hazardous exposures; such workers are unlikely to file OSHA complaints, whether because of the informal and/or temporary nature of their work assignments, fear of employer retaliation, or potential loss of employment. Some data have been collected for some worker groups, such as wildland firefighters, a group stressed by an increasing number of larger fires.
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From page 190... ...
• National Institute for Occupational Safety and Health (NIOSH) -- "Outdoor Workers Exposed to Wildfire Smoke" (NIOSH, 2021b)
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From page 191... ...
Conclusion 3-6: For worker groups not covered by RPPs, regulatory and public health agencies have no coordinated approach to reduc ing workplace inhalation hazards and supporting employers of such workers in doing so. Conclusion 3-7: Current respiratory protection technology for pro tecting workers from the diverse inhalation hazards they face has limitations.
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From page 192... ...
2011. Respiratory protective equipment, mask use, and respiratory outcomes among World Trade Center rescue and recovery workers.
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2021d. FAQS and communication resources for wildland firefighters.
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2021m. Meat and poultry processing workers and employers: Interim guidance from cdc and the occupational safety and health administration (OSHA)
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The New York Times, June 5. https://www.nytimes.com/2006/06/05/nyregion/05masks.html (accessed October 8, 2021)
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2017. Wildland fire smoke health effects on wildland firefighters and the public.
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2014. Exposures and cross-shift lung function declines in wildland firefighters.
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California Domestic Workers Coalition. https://www.cadomesticworkers.org/ news/on-the-frontlines-the-role-of-domestic-workers-and-day-laborers-in-confronting recent-wildfires-in-california (accessed October 8, 2021)
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2020. The occupational safety and health administration at 50: Protecting workers in a changing economy.
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2019. Wildland firefighter smoke exposure and risk of lung cancer and cardiovascular disease mortality.
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2021b. Outdoor workers exposed to wildfire smoke.
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2021f. Protecting workers: Guidance on mitigating and preventing the spread of COVID-19 in the workplace.
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2004. Baseline measurements of smoke exposure among wildland firefighters.
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https://www.jointcommission.org/-/media/tjc/documents/ covid19/public-statement-on-masks-from-home-w-faqs.pdf (accessed October 8, 2021)
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University of Illinois at Chicago. https://www.researchgate.net/ publication/321371398_After_the_Storm_Houston's_Day_Labor_Markets_in_the_ Aftermath_of_Hurricane_Harvey (accessed October 8, 2021)
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From page 206... ...
2021. Character ization of occupational smoke exposure among wildland firefighters in the midwestern United States.
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