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Is it time to change the filter?
Is it time to change the filter?
The importance of changing the filter of masks and masks
The big question that haunts users these days is why and when should filters be replaced 3M? And the first thing to know is that mask filters do not last forever. Each type has a useful life time, according to the time of use and the degree of exposure to contaminating agents.
In our first series'What's in the air you breathe?', we explore some of the different types of filters and how they work; In this edition, we'll talk about when and why you should change filters.
If after reviewing this information, you still have questions, click to ask a specialist Sekureco, who will be happy to help you.
The importance of changing filters
Once a gas and vapor filter has been used to its maximum capacity, it will no longer offer any protection. An overused particulate filter will still protect you, but it will be difficult to breathe, leading to fatigue and reduced productivity in your work activities.
The useful life of a filter can be affected by a series of factors, the main one will be the factory characteristics, then the concentration of contaminants in the air, the user's respiratory rate, humidity and the temperature to which they are exposed. It is best to determine a filter change schedule, a specific period of time after which the filters will be replaced.
A particulate filter should be changed when it is difficult to breathe; However, a filter change schedule can be developed considering typical clogging times at your workplace and applying a safety margin.
Another warning factor for changing the filter will be when the user can taste or smell the contaminant when wearing the mask. However, the correct way to define the filter change time correctly. This time period is best defined using objective data and a useful life calculation tool, such as the useful life calculation software 3M. Check the rest of tools and software 3M.
Alternatively, a filter change schedule can be developed taking into account the typical breakthrough times of gas and vapor filters in your workplace, and applying a safety margin. However, this method is less precise since it is based on human senses which are subjective and variable.
A combined filter must be replaced as soon as one of the parts (gases and vapors or particles) is saturated.
These are the factors that determine a mandatory filter change:
- Filter expiration date has passed
- The filter has been out of its packaging for 6 months or more (gas and vapor or combined filters)
- Filter shows signs of damage
To answer the most common questions about changing the protection filter, we have specified the following:
What regulations and standards govern the design and use of reusable filters and half masks?
Two main regulations govern respiratory protection.
Regulation (EU) 2016/425 of March 9, 2016 covers the design, manufactureand marketing of personal protective equipment.
Directive 89/656/EEC of November 30, 1989 addresses the minimum health and safety requirements for the use by workers of personal protective equipment in the workplace
EN 529 is a standard called 'Respiratory protection devices. Recommendations for selection, use, maintenance and storage'which can help you select, clean and maintain respiratory protective devices.
Many standards define requirements, testing and marking for masks and filters:
EN 136: Respiratory protective equipment. Full masks.
EN 140: Respiratory protective equipment. Half masks and quarter masks
EN 143: Respiratory protective equipment. Filters against particles
EN 14387: Respiratory protective equipment. Gas filters and combined filters
What types of filters exist?
Particle filters:They protect only against particles, that is, dust, vapors and fumes, aerosols, mold, bacteria, etc.
Filters for gases and vapors: Protects only against gases and vapors. There are different types of gas and vapor filters for different types of gases.
Combined filters: They protect against particles and gases. Different combinations of gas, vapor and particulate filters are used depending on the gas or vapor in the air.
Why should I replace filters regularly?
Particulate filters become clogged and become more difficult to breathe through, as a greater physiological load is imposed on the user. Gas and vapor filters begin to pass contaminants when their absorbents become saturated. This is known as penetration
Important: Filter selection should be made by a competent person with full knowledge of workplace respiratory hazards.
A bed of randomly oriented fibers is used to create the filter.
The treated fibers can be used to attract and trap particles as they flow into and through the filter material. Increasing the thickness and capture effectiveness of the filter material increases the filter's efficiency in capturing particles.
Particulate filters are tested in accordance with EN 143. The physics of particle capture tells us that the most difficult size range to retain corresponds to particles of an equivalent diameter of 0.02-0.2 microns and with a mass average diameter of about 0.3 to 0.6 μm. The particulate filter is tested with a sodium chloride test aerosol consisting mainly of particles of this size. There are four common filtration mechanisms: capture by interception, inertial impact, and capture by diffusion and electrostatic attraction.
In practice, particulate filters designed for respiratory protection will capture particles of all sizes; the main difference is the relative performance in the range between ~0.1 and 1 μm. Each class of filter must perform above a certain level against the test aerosol and then be classified according to EN 143 as explained below.
EN 143 uses a classification system to identify the filtration efficiency of particles at P1, P2, P3.
What is a P1, P2, P3 classification filter?
Particulate filters are classified according to their filtering efficiency. There are three classes of particulate filters: P1, P2 and P3 in ascending order of filtering efficiency.
A P1 filter shall have a filtration efficiency of at least 80% against the most penetrating particle size (0,3 to 0,6 μm). A P2 filter shall filter at least 94% of the particles including the most penetrating size. The P3 filter shall have a filtration efficiency of at least 99,95% against the most penetrating particle size.
What is an N95 filter level?
N95 is the classification of the US National Institute of Occupational Safety and Health (NIOSH), which is similar to P2 classification according to EN 143. N refers to sodium chloride and 95 refers to these products being at least 95% efficient compared to the sodium chloride test spray. NIOSH also has R- and P-type particulate filters for oily particles. In Europe, P2 masks are commonly used in healthcare settings.
How long do the particulate filters last?
As particulate filters are loaded with the pollutant, they actually limit the passage of particles more and can filter better
However, it is also more difficult to breathe through them. The user will notice this increased load and at some point will decide that the restriction is too high and will need to change the filter. The timing of this will also depend on the amount of particles in the breathing air. A job in a very dusty environment will obviously clog the filter more quickly than a relatively clean job. The decision point for switching will vary from person to person, as some people are more sensitive to increased respiratory load than others.
When should I change the particle filters?
Change particle filters 3M when:
• The breathing resistance is excessive for the user (this will vary depending on each person).
• The filter has some physical damage
• It becomes unhygienic, i.e. it has been coughed/sneezed and the interior is in an unacceptable state.
• Some workplaces, for example healthcare environments, may require replacement of masks/filters after each use due to infection control procedures.
Are there situations in which you should notuse particle filters?
There are several applications in which particle filters should NOT be used:
• When the ambient oxygen level is not guaranteed to be > 19.5%. Filters do not generate oxygen.
• To capture gases or vapors, they require a specifically rated gas/vapor filter.
• When the concentrations of contaminating particles in the air are high, that is, greater than what the standard allows for that type of device.
• When local regulations require the use of another specific type of equipment for specific applications.
How does a filter for organic gases and vapours work?
3M manufactures gas and vapor filters to help reduce user exposure to many different gases and vapors. To achieve this goal, the filters are filled with a material called activated carbon. Activated carbon is usually obtained from charcoal or renewable resources such as wood or coconut shells. It can be 'activated' by heating the material in nitrogen or steam to temperatures of approximately 800 – 900°C. The resulting material has a considerable number of micropores that help to adsorb various organic vapors. These micropores can be measured and optimized for specific product needs and performance.
When gases and vapors pass through an organic vapor filter, air is filtered as the vapors condense in the pores of the carbon. The vapors move
through the filter from one pore to the next. This occurs more rapidly for small volatile vapors with lower boiling points (e.g., acetone). Some migration of organic vapors may occur even during storage, so care should be taken before reusing the filter. Effective life is the time until vapors begin to escape from the filter.
Unlike particulate filters, service life is not indicated by changes in breathing resistance.
Instead, filters should be changed in accordance with local regulations; or due to irritation from the contaminant; or as calculated by 3MTM shelf life software, whichever comes first.
Activated carbon alone cannot absorb other types of gases or vapors such as acid gases, ammonia, formaldehyde, etc. In some cases, metals are addedand additional salts to carbon to selectively eliminate these compounds. For this reason, 3M offers various filters and masks to help protect workers in different environments and meet personal preferences
EN 14387 uses a classification system to identify the different types of contaminants these filters capture. The filters 3M follow this marking systemand color coding.
Factors influencing shelf life:
• Exposure concentration
• Temperature
• Humidity (water vapor takes up space in coal pores)
• Breathing rate
• Filter class
How do gas and vapor filters work?
These filters use absorbent material to absorb gas and vapor molecules. Typically, the absorbent is carbon grain that has been specifically treated. Depending on the chemical treatment of the coal surface, this material will absorb different types of gases or vapors.
EN 14387 uses a classification system to identify the different types of pollutants that these treated carbon grains capture, e.g. A, AX, B, E, K and Hg.
How long do gas and vapor filters last?
Filters for gases and vapors are classified according to their absorbent capacity. When increasing the capacity, the classifications are: Class 1, 2 or 3. This means that we can have type A1 or B2 or multi-gas filters, such as an A2B2E2K1.
The useful life (i.e. how long it will operate) of any gas and vapor filter is affected by many factors: concentration and nature of contaminants, respiratory rates, humidity levels, ventilation, temperature, type of carbon, etc.
To obtain an estimate of the useful life of the filters for gases and vapors of 3M, the use of useful life indicator software 3M allows you to calculate the estimated useful life in
the applicable working conditions. Contact your representative 3M for help with this process.
What is the difference between an A and AX filter?
A filter A is for organic gases and vapors with a boiling point >65 oC. p. e.g. Toluene, Xylene, MEK, Benzene, Alcohols.
An AX filter is for highly volatile organic solvents with a boiling point < 65 oC. p. for example:. This is methanol, 1,3-butadiene, acetaldehyde. These types of chemicals pass through the carbon bed over time. Therefore, EN 14387 specifies that AX filters must be changed after each shift. Manufacturers also specify maximum use concentrations and maximum use times, so be sure to follow the manufacturer' s instructions. AXs are tested with different gases than A filters and have additional desorption tests according to EN 14387.
When should I replace my gas and vapor filter?
Replace gas and vapor filters 3M:
• When the expiration date indicated on the sealed package has passed.
• If a smell or taste is perceived, when the user coughs or feels discomfort. This indicates that the filters are not changed withsufficiently frequently and that the filter change schedule must be adjusted. The sense of smell should not be relied upon as the primary indicator.
• Or according to your established filter change schedule.
To avoid smelling or tasting the contaminant when using gas and vapor filters 3M, follow these steps:
• When you get a new pair of gas and vapor filters 3M, check the expiration date on the backof the package.
• Write the date on the filters when you first remove them from the package.
• Use the filters on your mask in your normal work environment.
• If at any time you smell or taste the contaminant or irritation is detected, the filters should be replaced immediately.
• Take note of how long the filters lasted by comparing the date recorded on the filter and the current date.
• If work practices remain the same and vapor/gas levels are consistent, replace your filters at a more regular interval.
• Or according to your established filter change schedule.
Why can't I use smell or taste to determine when a gas and vapor filter needs to be changed?
Warning properties such as odor, eye irritation, and respiratory irritation were relied upon to indicate when chemical filter penetration was beginning. However, the warning properties depend on human senses that are not infallible because:
• There is considerable variation between people
• The sense of smell changes due to simple colds and other illnesses
• The odor of the contaminant may be masked by other odors
• Olfactory fatigue, in which, over a period of time, the sense of smell becomes tired and fails to detect high concentrations and, in particular, when the concentration gradually builds up, for example with hydrogen sulfide
• The odor threshold of some chemicals exceeds the levels at which they can be considered dangerous
• Some gases have no odor and therefore will not be detected, such as carbon monoxide
• Some chemicals have low odor threshold concentrations but do not pose a health hazard at these concentrations, such as methyl mercaptan.
Given the variability between individuals with respect to odor detection and differences in measuring odor thresholds, establishing a filter change schedule is a recommended practice.
What is a filter change program?
A filter change schedule is a specific period of time after which the chemical filter will be replaced. This time period can be established after considering the estimated useful life, workplace conditions such as contaminant concentration, relative humidity, temperature, work activities, usage pattern of respiratory PPE (e.g. , continuous or intermittent use), the presence of other materials, the possibility of migration/desorption of contaminants, the health effects of the gas or vapor and the quality of the warning properties, if any.
The filter change program should be based on objective information that will ensure that gas and vapor filters are changed before the end of their useful life.
The purpose of a change schedule is to establish the time period for replacing filters. The data and information used to establish the program must be included in the respiratory protection program.
Are there situations in which gas and vapor filters should not be used?
There are several applications in which gas and vapour filters should NOT be used:
• When the oxygen level is not guaranteed to be > 19.5%.
• For the capture of particles, for example, dusts, mists, fumes or fibers.
• When the contaminants present cannot be captured by the gas and vapor filter.
• When the concentrations of gas and vapor contaminants in the air are very high.
• When local regulations require the use of another specific type of device for certain applications.
Frequent questions
What is the useful life of the filters 3M?
As long as they are stored unopened in the original packaging, filters will last three to five years (depending on the product) from the date of manufacture.
How should I save my filters and my reusable half mask 3M?
When not in use, 3MTM masks and filters should be kept clean and dry, and away from oils, sunlight and corrosive atmospheres to prevent deterioration. A storage container or sealable bag can be used for this purpose.
Why should I use a particulate filter with my gas and vapor filters for some applications?
There are many situations where particulate and gas/vapor hazards occur at the same time. The particulate filter removes small droplets or particles in the air (e.g. spray paint mists). Filters for gases and vapors do not filter these particles. If a particle filter is not used, particles could be inhaled
There are many factors, such as exposure level, other controls, working frequency, breathing rate, etc., that affect how long a filter will last and when it should be changed. Some indicators for this are:
• For particle filters or masks, when breathing resistance becomes excessive for the user.
• When damage occurs such as a broken strap, a burnt hole in the mask, etc.
• It becomes unhygienic, i.e. it has been coughed/sneezed and the interior is in an unacceptable state.
• For combined filters (particles and gases and vapors),
the capacity of each type of filter will depend on the concentrations present in the filtered air; They will become saturated at different rates and will need to be changed when the time comes, probably at different times from each other.
• The useful life (i.e. how long it will operate) of any gas and vapor filter is affected by many factors: capacity, concentration and nature of contaminants, respiratory rates, humidity levels, ventilation, temperature, type of carbon , etc.
• Some workplaces, for example healthcare environments, may require replacement of masks/filters after each use due to infection control procedures.
Therefore, there is no specific time and the frequency of product replacement varies depending on the task, situation and product.
Are there dangers from suspended particles?
Get help. It's not always obvious what's in the air. But it's worth finding out and establishing an effective respiratory protection program. In 3M, we are happy to help you get started on the path to protection:
1 You feel the bases
- See safety data sheets
- Evaluate your environment and its applications
- Determine who is at risk
- Consider employee schedules, applicable materials and possible exposure
2 Start taking samples
- Collect air samples based on exposure
- Determine your specific course of action. It is possible that 3M i can help you with this
- Consider using lightweight diffusion monitors 3M for certain gases and vapors
3 Get your analysis
- Analyze his samples. An industrial hygiene lab could help.
- Use your analysis to buy your exposure levels with applicable occupational exposure limits
4 Select your protection
If the danger cannot be eliminated or controlled by other measures, use the 3M to find the right mask for your team.
Choose from a wide range of products including:
- Disposable masks
- Reusable masking stockings
- Motorised breathing and air supply equipment
- WAS
5 Implement and adapt
You must maintain a written respiratory protection program that may include:
- Review and continuous improvement
- Adjustment tests
- Continuing training of employees
The Importance of Monitoring: Gas Diffusion Monitors 3M
It is important to know the specific contaminant and exposure levels to determine the appropriate mask and filter for the work environment. This information will also help estimate the life of selected 3MTM gas and vapor filters. If exposure levels are not known, advice and monitoring is required.
Yes ok 3M does not carry out exposure assessments or monitoring, we offer gas diffusion monitors 3M (below) which may be a useful starting point. Gas diffusion monitors 3M they are simple but effective devices that collect certain pollutants from the air through the principle of diffusion. They facilitate the analysis of exposure to contaminants in the workplace, both personally and in the environment. These monitors are easy to use, just clip them to your shirt, work clothes or a pocket.
Get to know our new updated line.
Monitors for organic vapours, ethylene oxide and formaldehyde
• Easily attaches to lapel, collar or pocket
• No batteries, hoses or pumps
• Small and light: will not interfere with employee activities
• Can be used for environmental monitoring if there is sufficient air flow in the area
Detectors 3M
- 3500+ Organic Vapor Detector
- 3501+ Organic Vapor Detector, High Sampling Rate
- For use in the manufacture of motor vehicles
- Formaldehyde detector, 3721+
What's the difference between vapor monitors
organic 3500+ and 3501?
3501+ offers a higher sampling capacity for low concentrations or short-term exposure limit sampling (STEL).
How do I interpret the results?
Monitoring results can be compared with the corresponding occupational exposure limits (OEL).
The OELs for many common industrial pollutants can be found in the 3M.
How do I set up a filter change schedule?
Exposure monitoring data can be entered into the 3M in www.3M.com/sls to estimate the service life of gas/vapour filters 3M.
It's from: 3M The science. Applied to Life.
www.3M.com/es/seguridad