Masks and Respirators With Exhalation Valves Don't Protect Others
May 10, 2020
Note: This article was written during the Covid 19 pandemic, but applies to any situation where masks or facecoverings are worn are source control (to limit disease transmission or contamination from the wearer's exhaled particles).
Wearing masks in public, or when working with other people, helps prevent particles and droplets from the mask wearer's mouth and nose from infecting other people. Masks with an exhalation valve do not provide protection to other people, as exhalations go right out without being filtered or significantly slowed. The exhalation valve is like a vent that flaps open every time the user breathes out; It makes it more comfortable for the wearer, but exposes those around them to contamination.
Here are a few examples of exhalation valves on different styles of masks:
If your employees or customers have masks of this type, they need to wear a covering over the mask, such as a fabric mask, or a disposable medical mask. Healthcare workers can layer a surgical mask or procedure mask. Or, with workers that use elastomeric (re-usable rubber or silicone masks), it's often possible to set up some sort of cover on the vent area. Here is an example of an improvised fabric cover for the exhalation valve on an elastomeric respirator. It is held in place by two elastic loops that loosely go around the filter attachment points:
We should think of masks in two different categories:
-Personal protective equipment (PPE). Masks required for the safety of the persons wearing them, to protect them from some hazard (whether it's biohazards, concrete dust, paint vapors, etc). These require annual fit testing and training, and if selected and worn correctly, keep contaminants out of the user's lungs.
-Community protective equipment (CPE). Masks, usually reusable fabric or disposable medical masks, worn to reduce the risk of getting other people sick by slowing and capturing germs from exhalations, sneezes, coughing, speaking, etc. If there's a giant opening in the front of the mask that flaps open every time the wearer exhales, the community protective effect of the mask is compromised.
Respirators with an exhalation valve can be an excellent choice for personal protective equipment if the wearer is properly trained and fit tested. However, if the exhalation valve is not properly covered, this irresponsibly exposes others to danger if the mask wearer is infected, but not symptomatic (which is very common with Covid 19). This is an issue for all workplaces, but particularly in a healthcare setting, where a provider wearing a valved mask will be in close proximity to a patient to provide care and may infect them.
Additional suggestions that may apply to certain workplaces:
- If your workplace is open to clients or the general public, many people are uninformed about this issue with exhalation valves and may be wearing these types of masks. If possible, have some cheap medical or fabric masks available for them to wear instead, or layer over their existing mask to cover the exhalation valve.
- For industrial and construction workplaces with jobs that ordinarily require respirator use, where everyone in the work area is wearing a particulate respirator they have been trained on and fit tested for, it's probably not necessary to cover vents. But in areas where some people may not have masks, or only have fabric masks, or other looser fitting masks they haven't been fit tested for, vented masks need to be covered to protect others in the area from potentially getting sick.
- For companies that have or are considering prohibiting employees from wearing valved masks (when they are wearing personal masks on a voluntary basis, not due to a specific workplace hazard), this policy should be reconsidered. Vented masks are usually better designed in terms of the way they fit and the protection they provide for the wearer. However, vented masks definitely need to be covered in some way with an unvented mask, filter material or tightly woven fabric.
At a glance, a shop vacuum with a HEPA filter and a dedicated HEPA-rated dust extractor might seem to do the same job: collect dust and debris. In reality, the difference between them is substantial, especially for fine particulate control, worker protection, and regulatory compliance. Adding a HEPA filter to a standard shop vacuum improves filtration, but it doesn’t turn the unit into a true HEPA-rated system suitable for hazardous dust. Key takeaway: If you’re collecting fine dust from hazardous materials, use an extractor designed and certified for that purpose. Don’t rely on a shop vac with a retrofit HEPA filter. Here’s why: Most shop vacs leak around seals or bypass fine dust through motor vents, even if they use a HEPA filter. A proper dust extractor is designed from the ground up for fine dust control. All seals, gaskets, and joints are engineered to prevent leakage, and the entire system, not just the filter, is tested to meet HEPA performance. Shop vacs are built for high pulling force (static pressure) to pick up debris, nails, or sawdust through hoses. Dust extractors are designed to steadily move larger volumes of air (airflow) and catch fine, respirable dust particles before they disperse. Shop vacs clog quickly when used on fine dust; when the filter clogs, vacuum pressure drops, and more dust escapes into the air. Dust extractors include self-cleaning or pulse-clean mechanisms that shake accumulated fine dust off the filter. This leads to consistent pressure levels, and extends filter life. A shop vac is meant for short-term cleanup. Dust extractors are designed for longer periods of use, often with features like automatic tool-start functions, variable speed control, anti-static hoses, and spark-resistant motors for combustible dust safety. For operations covered under Cal/OSHA or Federal OSHA silica standards, or for controlling other hazardous respirable dusts like carbon, graphite, metals, wood, or asbestos, a simple shop vac with a HEPA filter is not sufficient. Hazardous materials require commercial-grade HEPA-filtered dust collection systems engineered and tested for fine particulate containment and exposure control.
Respirator cartridges for gas or vapor protection have a limited service life. They need to be changed before they become saturated and can no longer purify the air effectively. If an employer is using air-purifying respirators for protection against gases and vapors, Cal/OSHA T8 §5144(d)(3)(C) requires that the employer either: Use a cartridge with an end-of-service-life indicator (ESLI) that provides an indication to the user that the cartridge has reached the end of its service life. Unfortunately, ESLI cartridges are not available for most chemicals. Implement a time-based cartridge changeout schedule. This must be, per Cal/OSHA, “based on objective information or data that will ensure that ... cartridges are changed before the end of their service life. The employer shall describe in the respirator program the information and data relied upon and the basis for the ... cartridge change schedule.” Relying on users to detect the end of the cartridge service life by smell, taste, or irritation of the chemical passing through is not compliant as a primary method for cartridge changeout. It may be used only as a secondary safeguard to the employer's time-based changeout schedule. This is a common mistake: an employer identifies a potential respiratory hazard, buys respirators, and provides fit testing - yet skips the crucial step of a formal, documented hazard assessment and changeout schedule. For gas or vapor exposures, your written program should clearly specify: • The correct respirator type for the task • Appropriate cartridge or combination filter-cartridge • A time-based changeout schedule supported by data Safewest can help develop or review your respirator program, including hazard assessments and cartridge change schedules. Contact us to make sure your program is compliant and your employees are protected.
HAZWOPER (Hazardous Waste Operations and Emergency Response) training requirements apply to certain operations involving hazardous waste. These requirements dictate the amount, type and levels of training that employees working with hazardous waste must receive. The requirements for hazwoper training can be found in Cal/OSHA § 5192 and Federal 49 CFR 1910.120 . In general, there are three categories of hazmat operations, and specific training requirements for each. These three categories are hazmat site cleanup, emergency response, and operations at treatment, storage, and disposal facilities. Site Cleanup Cleanup and removal work at sites that have been identified by a government agency (state, federal, or local) as having an accumulation of hazardous substances that creates a threat to the health and safety of individuals or the environment or both. General site workers removing hazmat with potential exposure to hazardous substances and health hazards shall have 40 Hours of Training + 3 Days Supervised Field Experience. General site workers in areas where hazard levels have been fully identified, exposures are below published safety limits, there are no health hazards, no possibility of an emergency release, and respirators are not required shall have 24 hours of training + 1 day supervised field experience. Occasional/limited site workers (such as those doing monitoring or surveying) and are unlikely to be exposed to dangerous levels of hazmat shall have 24 hours of training + 1 day supervised field experience. Supervisors of general site workers shall meet the same training requirements as that category of general site worker, plus have an additional eight additional hours of specialized hazardous waste operations management training. All categories of site cleanup workers shall have 8 hours of annual refresher training. Emergency Response Emergency response to releases of, or substantial threats of releases of, hazardous substances, regardless of location. Awareness Level (FRA): Basic awareness, recognize hazmat threat, call for help. Competence based, no hourly requirement. Operations Level (FRO): Defensive response, contain and limit the release. Competence based, or 8 hours of training required. Hazmat Technicians and Hazmat Specialists: Direct response to stop a release of hazardous substances. Training scope and duties varies depending on position/role. 24 hours of training required. Incident Commander/Manager: Control and manage scene, implement response plans. 24 hours of training required. All emergency response workers shall receive annual refresher training or evaluation to demonstrate competency in their required areas. TSDF Operations Operations at Hazardous Waste Treatment, Storage, and Disposal Facilities (TSDFs) Workers are required to have 24 hours of initial training, and 8 hours annual refresher training.
The most important thing to know about snakebites is that people drastically overestimate both the likelihood and the severity of venomous snake bites in the US. Snakebites are fairly rare, and fatalities from snakebites are so unlikely (generally 5-10 per year in the entire country), a person is many times more likely to die from a lightning strike, or a heat-related emergency, or any number of other outdoor hazards. Prevention is simple. It is relatively simple to avoid most snakebites by being aware of where you step, not reaching or climbing on any area you haven't visually inspected first, and not approaching snakes to catch, kill, or photograph them. There are some significant misunderstandings about first aid measures for snake bites, many unfortunately perpetuated by uninformed first aid instructors and irresponsible equipment vendors. Do NOT apply suction. Avoid the use of commercial snakebite kits with suction pumps, like the Sawyer Extractor. See our article on venom extractors for more information on these ineffective and dangerous devices. Do NOT apply tourniquets or constricting bands. Do NOT cut the skin. Basic first aid measures are simple. Here's what you should do: Keep the person calm and avoid unnecessary movement. Why: Keeping the person's heartrate in a normal range slows the distribution of venom in their body. Remove watches, rings, and other tight fitting items. Why: These can constrict bloodflow if the person's limbs start to swell due to the venom. Call 911. If you do not have cellphone service, you will have to consider either finding a way to transport the person, or leaving them while you try to reach an area with cellphone service. Why: The only definitive care for a venomous snakebite is transport to a hospital for supportive care, and possibly anti-venom medication. For people working (or recreating) outdoors, mindfulness of where you place your feet and hands is your best defense against snakebites. If you will be in an area without cellphone coverage, investing in a means of emergency communication such as a satellite phone or messenger, personal locator beacon, two-way radio is the most important part of your emergency response plan. Three action steps for California employers: Review this information with your workers in April or March, which is when snake sightings will begin to increase. Ensure workplace first aid supplies do not contain outdated and dangerous supplies like snakebite kits and venom extractors. Ensure workers in remote areas have adequate means of emergency communications.