Prescription safety glasses and goggles without fogging
Prescription safety glasses and goggles enable protection from injury from debris, water, sun glare, snow, or other particles. Goggles come in various shapes and sizes to help with eye protection. Goggles are sometimes referred to as safety glasses, e.g. while working with hazardous chemicals or power tools.
There is much more to eye safety than just safety glasses. Workplace eye injuries can occur from foreign bodies going around or under a pair of safety glasses or ricocheting off the inner surface of the lens and hitting the eye. In some circumstances, a pair of safety goggles or a full mask may be more appropriate.
Don’t let smoke into your eyes or foreign objects.
Smoke can take considerable time to dissipate after fires.
Frame and lens materials have better heat resistance and antifogging properties than others. Fire grade positive seals of protective eyewear in cases of recent Tathra fires would have been ideal in reducing eye inflammation from smoke, as would correct masks and respirators.
Should safety eyewear fog up under hot or steamy conditions, increased exposure to a possible variety of hazards could ensue if removed.
The type of eye protector needed depends on the potential hazards. Depending on the needs, additional features for prescription safety glasses could include
• Nosepieces: adjustable, gel, rubber
• Temples: non-slip gel temples, spring-loaded hinges
• Anti-fog, scratch resistant and anti-reflective coatings Note: Lens coatings may render a lens less impact resistant. Generic near addition inserts and bifocals may be included in some clip-on, goggles and over-specs.
Blowtorch goggles are not the correct filters for arc welding, which requires radiation protection.
AS/NZS 1336: Recommended practices in occupational eye protection. Section 4 deals with the use of personal eye protectors in industrial settings and gives examples of specific hazards together with recommended eye protection. Section 7 deals with prescription safety glasses and eye protectors.
Prescription safety glasses and goggles
AS/NZS 1337: Occupational eye and face protection
This Standard sets down the requirements for non-prescription safety glasses and eye protection.
The UK National Health Service uses smart goggles with thermal imaging technology for examining wounds and injuries. They also can help in sharing live footage.
AUSTRALIAN STANDARDS EYE PROTECTION FOR SAFETY GLASSES AND GOGGLES
Eye injuries in the workplace are most commonly caused by grinding and welding, usually in the fishing, construction, manufacturing, agriculture, forestry, and mining industries. We can show you a range of comfortable protective glare-reducing safety eyewear.
Not wearing eye protection such as uvex over specs, full vision goggles or face shields, or prescription safety glasses can lead to an eye injury.
The best assurance is the use of the Standards Mark. Our suppliers are certified to use the Standards Mark.
Ugly Fish sunglasses,Ugly Fish safety glasses and goggles
All Ugly Fish Safety glasses feature shatterproof lenses and lightweight TR-90 frames that comply with the Australian Safety Standards. The stable of products is a prescription safety range designed for males and females, which is available through our suppliers such as HOYA, PSG and RX SAFETY.
Ugly Fish has evolved into designing a range of multi-functional (with positive seal) and professional user safety glasses for a diverse range of industries. WileyX safety eyewear also offers premium impact resistance. In addition, safety glasses allow air around the eye area instead of a seal against the face to avoid dust and splashes.
Face shields provide further protection and can also be worn over safe eyewear.
Sunglasses sold in Australia are not permitted to transmit UVB greater the 0.05% of total transmission and no more than 0.5% of total transmission of UVA, even less if the glasses are a category 4 sunglass. Because sunglasses are designed to protect against the sun, and there is no UVC at ground level, UVC is not required to be tested. However, occupational lenses need to be tested The Australian/New Zealand Standard AS/NZS 1338.1:2012 Filters for eye protectors – Filters for protection against radiation generated in welding and allied operations, and AS/NZS 1338.2:2012 Filters for eye protectors – Filters for protection against ultraviolet radiation regulates eye protection in the workplace for occupations both indoors and outdoors where artificial UV radiation may reach potentially hazardous levels.
Hazard reduction should include
• Possible reactions between dangerous goods and any plant, structures or other substances
• The chemical and physical reactions of dangerous goods
• Manufacturing, transfer or transport processes
• Plant and other structures used in the storage or handling of dangerous goods
• Any information about the hazardous properties
• The kind and characteristics of incidents which may be associated with dangerous goods
• The location of dangerous goods
• Environmental factors that may have an effect on the goods
All material safety data sheets for the chemical and physical properties of the dangerous goods need to be codified. These include but are not limited to:
• Physical state
• Flashpoint, fire point and explosive limits
• Viscosity
• Density
• Particle size
• Vapour pressure
• Solubility and pH
• Reactivity
• Boiling and/or freezing point or range
• Electrical and/or heat conductivity
• The nature and concentration of combustible products
Inherent hazards or subsidiary risks exist such as:
• Fire
• Explosion
• Toxic effects such as inhalation, ingestion, absorption through the skin or eyes, or corrosive action
Radiation damage and the eye
- Whilst Solar UVC is absorbed by the atmosphere, artificial sources of UVC may still be present. Depending on the material’s properties, UV and visible radiation wavelengths will transmit through the lens or be blocked or reflected. This is the case for UVC, UVB and UVA. Not all contact lenses will block UV transmission, just as not all prescription lenses block UV. Ocular absorption depends on the wavelengths and the age of the eye.
- UVC 100 – 280nm. Blocked by the earth’s atmosphere. No ocular absorption.
- UVB 280 – 315nm. Absorbed into the cornea. UVB can directly damage skin cells’ DNA and are the main rays that cause sunburn. They are thought to cause most skin cancers. Basal cell carcinoma (BCC) is the most common cancer in the world. Eighty per cent of BCCs occur in the head and neck region, of which 20 per cent occur on the eyelids,
- UVA 315 – 380nm. Transmitted into the ocular media. The longer the wavelength, the deeper the penetration. These rays are linked to long-term skin damage such as wrinkles, but they are also thought to play a role in some skin cancers.
Gamma rays, X-rays, and high ultraviolet radiation can be a health hazard as they penetrate the body and transmit through spectacle glasses. However, it will appear denser than soft tissues. This ionising radiation can cause cell damage ( from spectroscopy studies) instead of the non-ionising radiation of visible light wavelengths and lower.
The longer wavelength and lower energy microwaves and radio waves will penetrate the body with some absorption. The eyes are one of the most sensitive organs in the body for microwaves. The microwaves excite the water molecules in the body and cause heat damage effects at high levels.
Special shielding similar to faraday cages is required to block this kind of radiation. Glasses do not prevent transmission.
All standards for electromagnetic radiation transmitting equipment, including those emitting microwave radiation, set safe limits, which are much below what will cause damage to the body.
Though the sun emits all of the different kinds of electromagnetic radiation, 99% of its rays are visible light, ultraviolet rays, and infrared rays (also known as heat).
Sixty per cent of all eye injuries happen in the workplace, so every workplace, regardless of industry, should have eye safety procedures. Many people need education in this regard.
Anti-fog treatments usually work either by application of a surfactant film or by creating a hydrophilic surface. Anti-fog agents are usually available as spray solutions, creams and gels, and wet wipes, while more resistant coatings are often applied during complex manufacturing processes.
There are four critical elements in compliant prescription eyewear.
1.) Appropriate frame
2.) Appropriate lens material and thickness
3.) Appropriate fitting
4.) Labelling and assuring compliance
Night vision goggles
Astronomy and meteorology use dark adaption before going outside at night to help the eyes adapt to the dark. Night Vision goggles amplify light and infrared, producing a green output image far better than fully dark adapted eyes would otherwise get. Several generations have improved sensitivity, signal, and resolution since the 1950s. Human vision is confined to a small portion of the visible light, in the electromagnetic spectrum. Due to different biology and anatomy, many animals have better night vision than humans.
Safety glasses allow air around the eye area instead of a seal against the face to avoid dust and splashes.
Face shields provide further protection and can also be worn over the safety eyewear interior; water vapour condenses onto a single lens because the lens is colder than the vapour, although anti-fog agents can be used.
Antifogging eyewear generally has two layers of airtight lenses (inner lens warmer outer lens colder) to prevent the interior from becoming “foggy” by keeping the temperature of the inner lens close to that of the interior water vapour.
Ventilation safety glasses can prevent sweat from building up inside. The use of proper protective eyewear can prevent most eye injuries and even smoke-related inflammation.
People who already suffer from eye conditions such as dry eye, blepharitis, or allergic conjunctivitis are especially susceptible to the burning and stinging eye pain that smoke can cause. Fogging is the number one vision-related barrier to wearing safety eyewear.
SAI global certified anti-fog coatings are now available.
Handy belt cases can have them at the ready, so you not caught out.
Clip-on Attached to a prescription spectacle or Plano-lens frame, normally when glare is the only risk.
Over glasses Need to have correct fit/instability.
Wide vision Safety glasses – often resembling sunglasses. Additions such as frame collars provide peripheral protection.
Inserts – Eye protectors with a prescription carrier.
Wide vision goggles – Flexible frame or rigid with a separate cushioned fitting surface and headband.
Welding goggles – added protective measures for welding with air vents and anti-fog coatings.
Face shields can provide additional protection against extreme temperatures to the face, blasts and high impact.
Smoke being a mixture of chemicals in gaseous, liquid and solid forms, contains different-sized smoke particles. Smoking tobacco is detrimental, as is smoke in your eyes. Generally, eye irritation from smoke can be relieved by flushing with artificial tears and cold compresses, depending upon the circumstances. Keeping artificial tears in the refrigerator and cold compress over your eyes is also soothing.
Stay indoors. Particularly if you have an underlying condition that makes you more sensitive to the smoke, such as dry eye,
Protect your eyes. Specialty designed eyewear can be prescribed to patients with dry eye. It can be a great option for anyone experiencing sensitivity to smoke in the air. Close-fitting glasses or sunglasses will provide at least some barrier that slows the stream of air going into your eyes.
Improve your indoor air with an air filter.
Wind makes the moisture in your eyes evaporate so that lubricating drops can help against exposure and heat. Humidifiers can be helpful. Direct and reflected UV exposure can cause inflammation of the eye, skin cancer and cataracts and so it should be a year-round priority to wear sunglasses.
Uvex disposable Faceshield
• Protective face shield for single-use, one size fits all head sizes in the range 54-64 cm. Fixation on the head with an elastic band, PET lens, 0.3 mm, inside fog-free
• Soft foam inner padding ensures high wearing comfort even when worn for longer periods. It helps to keep the face free from dirt and liquids
• Suitable to keep the face free from contamination of body fluids such as blood. Not suitable for protection against mechanical hazards, such as flying particles with higher energy
• Space-saving flat-fold packaging
Applicable Standards:
• EN 166 PPE category II
• TGA approved
• ARTG No 335203
• Complies with ASNZS 1337.1.2010, Clause 3.3.4
(splash resistance test only)
Headband Textile elastic band – white, Lens Material PET 0.3mm, Lens Coating Clear Anti-fog (inside)
COVOID-19 AND SAFETY SPECTACLES
According to the American Academy Of Ophthalmology, COVOID-19 infection also can occur through virus particles entering the eyes. However, there are ways we can help reduce this from happening by protecting yourselves with wrap personal protective eyewear.
More and more people are taking extra precautions, opting to wear Safety Eyewear & Sunwear for everyday protection and also to help reduce the spread of COVID-19 via contact with the eyes.
Prescription safety eyewear allows
• Increased comfort, improved vision
• Reduced weight.more fashionable
• Less reflection, Less restriction on movement and visual field
Swimming goggles versus diving masks
Other goggle types and uses
The problem with having any sort of clip-in spectacles sitting inside a scuba mask is fogging. Three surfaces can fog up and are impossible to clear once submerged.
Choices ideally are custom laminated distance correction or for scuba dives a D-Seg Bifocal is ideal.
HOW TO FIT FACE MASK AND AVOID FOGGING
The face mask should not move when breathing occurs and can be sealed further with micropore tape. A tissue can even be used over the bridge of your nose, so the moisture from your breath will be absorbed by the tissue instead of hitting your glasses lenses. If wearing contact lenses isn’t an option, the face mask needs to fit tightly around the nose and cheeks to reduce the amount of breath escaping and causing condensation on the lenses. Washing up liquid wiped on and off (but not washed off) does help. The seal to the face along the top of the mask is important because a loose-fitting mask will direct the warm, humid exhaled air up the face.
Conversely, a loose fit to the lower face allows the exit away from the upper face, but a secure fit is better for Covid 19 protection. The straps on the mask can also be adjusted for a more secure fit.
Wear the face mask high over the nose as comfortably possible, allowing the wearer to rest their glasses over the mask to act as a seal.
The aim is to prevent the warm air from escaping through the top of the mask. Clean your glasses the right way.
READ MORE
Some people wash the spectacles with soapy water and shake off the excess, air dry or dry the lenses gently with a microfibre cloth. This is inferior to anti-fog wipes that can prevent the lenses from misting when the face mask is worn.
The soapy water puts a residue on the lens that does help, but not ideal over the long term as the residue builds up. If the lens is matched to the ambient temperature, the risk of fogging is minimised.
Anti-fogging agents and treatments are chemicals that prevent the condensation of water in the form of small droplets on a surface that resembles fog. Anti-fog treatments were first developed by NASA for helmet visors during Project Gemini and are now often used on transparent glass or plastic surfaces used in optical applications, such as the lenses and mirrors found in glasses, goggles, camera lenses, and binoculars. The treatments minimise surface tension, resulting in a non-scattering film of water instead of single droplets. This works by altering the degree of wetting. Anti-fog additives can also be added to plastics, where they exude from the inside to the surface. Some antifog products, especially silicone-based, can smear the lenses or charge the top layer of the lens, so the droplets don’t aggregate.
The following substances and demisters are used as anti-fog agents:
Surfactants that minimize the surface tension of the water:
Detergents such as shampoo, soap, or shaving cream applied as a solution and wiped off without rinsing
Hydrophilic coatings that maximize the surface energy:
Polymers and hydrogels:
Gelatin
Beeswax
Colloids and nanoparticles:
Titanium dioxide becomes highly hydrophilic under UV light.
Optifog treatment on lenses is ideal also.
The 3-ply surgical mask is the ideal CE and FDA approved Covid 19 mask. The quality of different brands can vary despite appearing similar.
The three 3 layers have an outer hydrophobic(waterproof) translucent non-woven layer, a middle melt-blown layer that contains electrostatic charges (contain droplets by electrostatically adsorbing them on the surface; hence it cannot infiltrate the mask) and an inner soft, absorbent non-woven layer that is intended to absorb water, sweat, saliva and spit. The middle layer, which traps bacteria from entering or exiting the mask, should not be too porous. This will ensure the mask can catch the percentage of bacteria it’s supposed to. The difference of 3-ply surgical mask to fashion masks or ordinary hygiene mask
Fashion masks, ordinary disposable dust masks or 2-ply hygiene masks will not protect you from the virus.
e.g. washable cotton or sponge that is reusable protect against air pollution or pollen allergy but useless against viruses and bacteria.
Ordinary 2-ply hygiene mask from fabric or non-woven material is also disposable but lacks a melt-blown filter layer containing viruses and bacteria. Filtering facepiece respirators (FFR), sometimes called disposable respirators, are subject to various regulatory standards worldwide. Many masks being sold currently have nose bridges are sewn into them – flexible strips that allow you to bend and shape them to fit your nose for comfort, and less moisture can escape to fog your glasses. Importantly regulatory standards are needed to specify certain required physical properties and performance characteristics for respirators to claim compliance with the particular standard. During pandemics or emergencies, health authorities often reference these standards when making respirator recommendations, stating, for example, that certain populations should use an “N95, FFP2, or similar” respirator.
• N95 (United States NIOSH-42CFR84)
• FFP2 (Europe EN 149-2001)
• KN95 (China GB2626-2006)
• P2 (Australia/New Zealand AS/NZA 1716:2012)
• Korea 1st class (Korea KMOEL – 2017-64)
• DS2 (Japan JMHLW-Notification 214, 2018)
Respirators certified as meeting these standards can be expected to function very similarly to one another.
Flow rates specified by these standards for the inhalation and exhalation resistance tests may differ.
| Certification/ Class (Standard) | N95 (NIOSH-42C FR84) | FFP2 (EN | KN95 (GB2626-20 | P2 (AS/NZ | Korea 1st Class (KMOEL – | DS2 (Japan |
| Filter performance – (must be ≥ X% efficient) | ≥ 95% | ≥ 94% | ≥ 95% | ≥ 94% | ≥ 94% | ≥ 95% |
| Test Agent | NaCl | NaCl and paraffin oil | NaCl | NaCl | NaCl and paraffin oil | NaCl |
Filter performance – the filter is evaluated to measure the reduction in concentrations of specific aerosols in the air that passes through the filter.
Test agent – the aerosol that is generated during the filter performance test.
Total inward leakage (TIL) – the amount of a specific aerosol that enters the tested respirator facepiece via filter penetration and face seal leakage while a wearer performs a series of exercises in a test chamber.
Inward leakage (IL)– the amount of a specific aerosol that enters the tested respirator facepiece while a wearer performs normal breathing for 3 minutes in a test chamber. The test aerosol size (count median diameter) is about 0.5 micrometre.
Pressure drop – the resistance air is subjected to as it moves through a medium, such as a respirator filter.
READ MORE ON SURGICAL MASK TECHNOLOGY
Although their appearance is often similar, respirators are designed and engineered for distinctly different functions than surgical masks. The amount of exposure reduction offered by respirators and surgical masks differs. The National Institute for Occupational Safety and Health (NIOSH) and the Centers for Disease Control and Prevention (CDC) recommend using a NIOSH-certified N95 or better respirator for the protection of healthcare workers.
The most frequently used respirator in healthcare settings is the N95 filtering facepiece respirator (FFR).
Evolution of Respiratory Protection against Particulate Exposures
Early surgical masks were constructed from layers of cotton gauze.
A surgical mask is a loose-fitting, disposable device that prevents the release of potential contaminants from the user into their immediate environment. In the U.S., surgical masks are cleared for marketing by the U.S. Food and Drug Administration (FDA). They may be labelled as surgical, laser, isolation, dental, or medical procedure masks. They may come with or without a face shield.
Modern respirator maks derived from the need to protect miners from hazardous specks of dust and gases, soldiers from chemical warfare agents, and firefighters from smoke and carbon monoxide.
The filter mask must be able to capture the full range of hazardous particles, typically within a wide range of sizes (<1 to >100 µm) over a range of airflow (approximately 10 to 100 L/min). Second, leakage must be prevented at the boundary of the facepiece and the face.
Filter Performance
The filters used in modern surgical masks and respirators are considered “fibrous” in nature—constructed from flat, nonwoven mats of fine fibres. Fibre diameter, porosity (the ratio of open space to fibres) and filter thickness all play a role in how well a filter collects particles.
Three “mechanical” collection mechanisms operate to capture particles in all fibrous filters: inertial impaction, interception, and diffusion. Inertial impaction and interception are responsible for collecting larger particles, while diffusion is the mechanism responsible for collecting smaller particles. In some fibrous filters constructed from charged fibres, an additional mechanism of electrostatic attraction also operates. This mechanism aids in the collection of both larger and smaller particle sizes. This latter mechanism is fundamental to filtering facepiece respirator filters that meet the stringent NIOSH filter efficiency and breathing resistance requirements because it enhances particle collection without increasing breathing resistance.
How do filters collect particles?
These captures, or filtration, mechanisms are described as follows:
Filtration mechanisms
Inertial impaction: With this mechanism, particles having too much inertia due to size or mass cannot follow the airstream as it is diverted around a filter fibre. This mechanism is responsible for collecting larger particles.
Interception: As particles pass close to a filter fibre, they may be intercepted by the fibre. Again, this mechanism is responsible for collecting larger particles.
Diffusion: Small particles are constantly bombarded by air molecules, which causes them to deviate from the airstream and come into contact with a filter fibre. This mechanism is responsible for collecting smaller particles.
Electrostatic attraction: Oppositely charged particles are attracted to a charged fibre. This collection mechanism does not favour a certain particle size.
In all cases, once a particle comes in contact with a filter fibre, it is removed from the airstream and strongly held by molecular attractive forces. It is challenging for such particles to be removed once they are collected. There is a particle size at which none of the “mechanical” collection mechanisms (interception, impaction, or diffusion) is particularly effective. This “most penetrating particle size” (MPPS) marks the best point to measure filter performance. If the filter demonstrates a high level of performance at the MPPS, then particles both smaller AND larger will be collected with even higher performance.
Filters do NOT act as sieves. One of the best tests of a filter’s performance involves measuring particle collection at its most penetrating particle size, ensuring better performance for larger and smaller particles. Further, the filter’s collection efficiency is a function of the size of the particles and is not dependent on whether they are bioaerosols or inert particles.
Respirator filters must meet stringent certification tests on “worst-case” parameters, including:
A sodium chloride (for N-series filters) or a dioctyl phthalate oil (for R- and P-series filters) test aerosol with a mass median aerodynamic diameter particle of about 0.3 µm, which is in the MPPS-range for most filters.
Airflow rate of 85 L/min, which represents a moderately-high work rate
Conditioning at 85% relative humidity and 38°C for 24 hours before testing
An initial breathing resistance (resistance to airflow) not exceeding 35 mm water column* height pressure and initial exhalation resistance not exceeding 25 mm water column height pressure
A charge-neutralized aerosol
Aerosol loading conducted to a minimum of 200 mg, which represents a very high workplace exposure.
The filtering efficiency cannot fall below the certification class level at any time during the NIOSH certification tests.
* Millimeters (mm) of the water column is a unit for pressure measurement of small pressure differences. It is defined as the pressure exerted by a column of water of 1 millimetre in height at defined conditions, for example, 39°F (4°C) at standard gravity.
As a result of these stringent performance parameters, fibre diameters, porosity, and filter thicknesses of all particulate filters used in NIOSH-certified respirators, including N95s, are designed and engineered to provide very high levels of particle collection efficiencies at their MPPS.
On the other hand, manufacturers of surgical masks must demonstrate that their product is at least as good as a mask already on the market to obtain “clearance” for marketing. Manufacturers may choose from filter tests using a biological organism aerosol at an airflow of 28 L/min (bacterial filtration efficiency) or an aerosol of 0.1 µm latex spheres and a velocity ranging from 0.5 to 25 cm/sec (particulate filtration efficiency). It is important to note that the Food and Drug Administration specifies that the latex sphere aerosol must not be charge-neutralized.
The generation of the test aerosol can impart a charge on a higher percentage of the aerosolized particles than may normally be expected in workplace exposures. Like those used in the NIOSH tests, a charge-neutralised test aerosol has the charges on the aerosolized particles reduced to an equilibrium condition. Therefore, higher filter efficiency values than would be expected with the use of charge-neutralized aerosols may result from collecting charged particles by the filters’ electrostatic attraction properties. Additionally, allowing the manufacturer to select from a range of air velocity means that the test results can be easily manipulated. In general, particles are collected with higher efficiency at lower velocity through a filter.
These aspects yield a test that is not necessarily “worst case” for a surgical mask filter. However, because the performance parameters for surgical masks are less stringent than those required for filters used in NIOSH-certified respirators, the fibre diameters, porosity, and filter thicknesses found in surgical masks are designed with significantly lower levels of particle collection efficiencies at their MPPS.
How do surgical mask and respirator filters perform?
Respirator filters that collect at least 95% of the challenge aerosol are given a 95 rating. Those that collect at least 99% receive a “99” rating. And those that collect at least 99.97% (essentially 100%) receive a “100” rating. Respirator filters are rated as N, R, or P for their level of protection against oil aerosols. This rating is important in industry because some industrial oils can remove electrostatic charges from the filter media, thereby degrading (reducing) the filter efficiency performance. Respirators are rated “N” if they are not resistant to oil, “R” if somewhat resistant to oil, and “P” if strongly resistant (oil proof). Thus, there are nine types of particulate respirator filters:
N95, N-99, and N-100
R-95, R-99, and R-100
P-95, P-99, and P-100
Respirator filters are tested by NIOSH at the time of application and periodically afterwards to ensure that they continue to meet the certification test criteria. The FDA does not perform an independent evaluation of surgical mask filter performance, nor does it publish manufacturers’ test results. Therefore, it is difficult to find information about the filter test results for FDA-cleared surgical masks in many cases. The class of FDA-cleared surgical masks known as Surgical N95 Respirators is the one clear exception to this uncertainty of filter performance. This is the only type of surgical mask that includes evaluation to the stringent NIOSH standards. All members of this class of surgical masks have been approved by NIOSH as N95 respirators before their clearance by the FDA as surgical masks. Therefore, the FDA, in part, accepts the NIOSH filter efficiency and breathing resistance test results as exceeding the usual surgical mask requirements.
In studies comparing the performance of surgical mask filters using a standardized airflow, filter performance is highly variable. For example, the collection efficiency of surgical mask filters can range from less than 10% to nearly 90% for different manufacturers’ masks when measured using the test parameters for NIOSH certification. Therefore, published results on the FDA-required tests (if available) are not predictive of their performance in these studies.
It is important to keep in mind that the overall performance of any facepiece for particulate filtering depends, first, on good filter performance. A facepiece or mask that fits well to the face but has a poor filter will not provide a high level of protection.
Respirator and Surgical Mask Fit
Because respirator filters must meet stringent certification requirements, they will always demonstrate a very high level of collection efficiency for the broad range of aerosols encountered in workplaces. There has been some recent concern that respirator filters will not collect nano-sized particles, but research has demonstrated that such particles are collected with efficiencies that meet NIOSH standards. This is not surprising because NIOSH tests employ small, charge-neutralized, relatively monodisperse aerosol particles and high airflow.
Thus, the most important aspect of a NIOSH-certified respirator’s performance will be how well it fits the face and minimizes the degree of leakage around the facepiece. This must be measured for each individual and their selected respirator. Selecting the right respirator for a particular workplace exposure depends largely on selecting the right level of protection.
Respirator fit depends on two important design characteristics:
Whether the respirator operates in a “negative pressure” or “positive pressure” mode
The type of facepiece and degree of coverage on the face
Respirators that operate in a “negative pressure” mode require the wearer to draw air through an air-cleaning device (filter or chemical cartridge) into the facepiece, which creates a negative pressure inside the respirator in comparison to that outside the facepiece. A “positive pressure” respirator, on the other hand, pushes clean air into the facepiece through the use of a fan or compressor, creating a positive pressure inside the facepiece when compared to the outside. Negative pressure respirators inherently offer less protection than positive pressure respirators because inward leakage occurs more easily in the former.
READ MORE ON RESPIRATORS AND FILTERS
Respirators are classified by the type of hazard they protect against.
Negative-pressure respirators rely on the wearer to pull air in through cartridges or filter.
Disposable respirators, also known as filtering facepieces, are used to help protect against some particulate hazards. They’re lightweight and require no maintenance since they’re discarded after use.
Reusable
Reusable respirators can be used with particulate filters, gas and vapor cartridges or combination cartridges, which may need to be replaced on a schedule or as needed.
Half-Face
Half-face respirators cover the lower half of the face, including the nose and mouth.
Full-Face
Full-face respirators cover the eyes and much of the face and can sometimes replace the need for safety glasses.
Positive Pressure
Positive-pressure respirators do the work of pushing air to the respirator headtop or facepiece; they can either be powered-air, using a battery-powered blower to pull air through a filter, or supplied-air, bringing clean air through a hose from a source outside of the contaminated work area
Tight-fitting respirators must be fit-tested when use is required
Loose-Fitting
Loose-fitting respirators typically have a hood or helmet.
Self-contained breathing apparatus (SCBA) is classified as a positive pressure supplied air respirator, but is different from all other respiratory equipment in that the user carries the source of the clean air with them in a tank.
Cartridges and/or Filters
Per AS/NZS 1715 there are 3 different classes of particulate filters, P1, P2 and P3.
The negative pressure particulate categories are based facepiece coverage. All particulate filtering facepieces that cover the nose and mouth area only can achieve only a P1 or P2 classification. A P3 classification can ONLY be achieved when worn with a full facepiece.
Class P1 particulate filters are used against mechanically generated particulates e.g. silica and wood dust.
Class P2 particulate filters are used for protection against mechanically and thermally generated particulates or both e.g. metal fumes.
Class P3 particulate filters are used for protection against highly toxic or highly irritant particulates e.g. beryllium (when worn with a full facepiece).
Certain contaminants may have specific respiratory selection criteria outside this guide e.g. asbestos.
Gas and vapour cartridges categories are distinguished by their filter type and class.
Filter type A = Certain organic vapours (boiling point above 65⁰C) from solvents such as those in paints and thinners (cartridge label colour = brown)
Filter type B = Acid gases such as chlorine, hydrogen sulfide (sulphide) and sulfur dioxide (cartridge label colour = grey)
Filter type E = Vapours from sulfur dioxide (cartridge colour = yellow)
Filter type ABE = are suitable for both certain organic vapours/acid gases and sulfur dioxide e.g. solvents, chlorine and sulfur dioxide (cartridge label colour = brown, grey and yellow)
Filter type K = ammonia gas (cartridge label colour = green)
Filter type ABEK = are suitable for both certain organic vapours/acid gases, sulfur dioxide and ammonia (cartridge label colour = brown, grey, yellow and green)
(AS) 4381: 2015 SINGLE USE FACE MASKS
Requires Instructions For Use, “The masks should be packed such that each mask can be removed without becoming entangled in another”
| CHARACTERISTICS | LEVEL 1 | LEVEL 2 | LEVEL 3 | TEST METHOD | |
Level 1 barrier medical face mask materials are evaluated for resistance to penetration by synthetic blood at the minimum velocity specified, bacterial filtration efficiency and differential pressure. APPLICATIONS: For general purpose medical procedures, where the wearer is not at risk of blood or bodily fluid splash or to protect staff and/or the patient from droplet exposure to microorganisms (e.g. patient with upper respiratory tract infection visits GP) | Level 2 barrier medical face mask materials are evaluated for resistance to penetration by synthetic blood at the middle velocity specified , bacterial filtration efficiency and differential pressure. APPLICATIONS: For use in emergency departments, dentistry, changing dressings on small or healing wounds where minimal blood droplet exposure may possibly occur (e.g. endoscopy procedure) | Level 3 barrier medical face mask materials are evaluated for resistance to penetration by synthetic blood at the maximum velocity specified, bacterial filtration efficiency and differential pressure. APPLICATIONS: For all surgical procedures, major trauma first aid or in any area where the health care worker is at risk of blood or bodily fluid splash (e.g. orthopaedic, cardiovascular procedures) | |||
| Bacterial Filtration Efficiency (BFE) % | ≥ 95% | ≥ 98% | ≥ 98% | ASTM F2101-14 or EN 14683:2014 | |
| Perticulate Filtration Efficiency (PFE) % (0.1 μm) | Not Required | Not Required | Not Required | N/A | |
| Differential Pressure (Delta P) mm H2O/cm2 | < 4.0 | < 5.0 | < 5.0 | EN 14683:2014 |
| Resistance to penetration by synthetic blood (fluid resistance) min pressure in mm Hg for pass result | 80mm Hg | 120mm Hg | 160mm Hg | ASTM F1862 / F1862M-13 or ISO 22609 |
The most prevalent eye diseases causing vision loss in Australians are age-related macular degeneration, cataract, glaucoma and diabetic retinopathy. Combined with uncorrected refractive errors (problems that could be fixed with prescription glasses), these conditions account for over 90 per cent of vision loss among older Australians. Changing light conditions can increase the risk.
By the age of 65, humans need triple the light to see what they did at 20 years old. It also takes people over 60 far longer to adjust to changes in light, making it difficult to judge distance and depth.
VISION AND FALLS
Vision is a huge part of how we perceive and navigate our world, however as we get older our sight deteriorates, with conditions such as glaucoma and cataracts common amongst people over 60.
As a consequence of this, vision problems in seniors can also increase the likelihood of other complications such as falls.
Seventy-five per cent of all injury hospitalisations in Australia are caused by a fall for those aged 65 and over, so the numbers are significant. The mortality rate associated with falls also greatly increases with age, with falls accounting for 84% of accidental deaths in persons 65 years and over.
Research from the University of Bradford has shown that as we age there is a greater chance of tripping over obstacles, misjudging the position of steps or kerbs, or not recognising a slippery surface. Stairs, steps and kerbs are the most likely reason for falls.