For maximum eye and lung protection nothing beats a powered face shield respirator.
In the shop, while your body presents the largest target for injuries because of its sheer size, and the fact that your hands are often in close proximity to sharp edges, it is an injury or damage above the shoulders that can have the most debilitating and lasting effect. We should all be in the habit of wearing eye protection any time we are working in the shop. When you fire up that noisy planer or sander you should already be wearing proper hearing protection as well. To complete the picture, and to protect your lungs from fine particulate found suspended in the air in every wood shop, the final piece of personal protective equipment you should be reaching for is a good quality dust mask or respirator.
When I worked in the construction industry, I wore a variety of different dust masks, respirators, safety glasses and safety goggles. During hot summer days this gear is uncomfortable and confining, while in the winter your warm breath will condense the moment it hits a cold surface. Flimsy dust masks made to cover your nose and mouth offer little protection from the most dangerous particulate and will typically divert your breath upwards toward your eye protection where it will invariably condense and obscure your vision as the lenses fog up. Facial hair makes getting a good seal with a mask or respirator even more problematic. To further complicate matters, wearing earmuffs over a respirator means you’ll need to remove them before you can remove your breathing gear.
Several companies have attempted to address these issues by combining these three pieces of personal protective equipment into one package. Triton (tritonwoodworking.com), and Trend (trend-ca.com) both offer systems that combine three pieces of personal protective equipment into one package. The result, in both cases, is a self-contained face shield that provides full-face protection and a constant supply of clean filtered air. To guard your lungs, these units provide a battery powered filter/fan combination that directs clean filtered air to the top of the face shield. The filtered air is pumped into the face shield through vents at the top of the shield and then it flows over the face finally exiting via holes at the bottom of the shield. These two models both achieve the same result, but they come at it from slightly different perspectives.
The US National Institute for Occupational Safety and Health (NIOSH) provides efficiency ratings for respirator filters. N95 is a rating for respirators that filter out 95% of airborne particles (not gases or vapours) larger than .03 microns.
The Triton Powered Respirator system ($219.99) comprises two distinct parts, the face shield, consisting of a helmet and visor, which is worn on the head, and the filter/battery pack, which is self contained and is worn on a belt around the waist. The fan and filter pack are then connected to the back of the helmet by a hose. There are two N95 rated filters at the top of the battery pack, and a pre-filter located on the bottom. The Triton, which is rated at minimum 5.3 cubic feet of air flow per minute, will remove 99% of particles down to one micron in size and 95% of the particles down to .3 microns. A built-in battery charger recharges the two NiCad batteries in eight hours, but the lack of a quick charger means that you’ll need to get in the habit of establishing a regular charging routine to be sure the batteries are charged when you need them. The Triton doesn’t offer the convenience of being able to plug in a spare battery while you charge the one that you have drained. The batteries are soldered in place and can’t be removed.
Having the battery slung on your hips makes for a lighter helmet, and at around two pounds, the Triton is comfortable to wear, even for those with prescription glasses or beards. There is a ratcheting adjustment knob at the back of the helmet for adjusting the fit. The rigid hose that extends from the back of the helmet to the battery pack could be somewhat longer (and more flexible). When the fan is turned on the noise level in the helmet increases noticeably (we measured it at 77.6 dB). The visor is made of a polycarbonate material, and is quite clear, with little distortion. A pair of integrated ear muffs with a 23dB rating are attached to the hard hat; these tilt out and can be adjusted upwards and downwards for a comfortable fit. The visor can be opened to one of three positions. A replaceable shroud (face seal) covers the neck and is held tightly in place with a draw cord. The shroud does an excellent job of keeping dust from entering the bottom of the helmet. I was very pleased with the performance of the Triton, and despite a couple of shortcomings (nonremovable battery, short, rigid hose), it offers excellent protection to anyone working in a high dust environment. The Triton comes with a three year warranty.
The Trend Airshield Pro ($399.00, canadianwoodworker.com) is the most recent version of their powered face shield. Unlike the Triton version, the Airshield Pro is a single, self-contained unit with all of the filtering done on the headpiece itself. The unit ships with a 3.5Ah Ni-MH battery that can be recharged without removing it from the helmet; the user can also purchase a second battery, which can be charged on an external charger and inserted when needed. Replacement of the battery is quick and easy, and battery life has been doubled on this new version, with a run time of eight hours. As an added bonus, an audible beep sounds when the battery is low. The Airshield Pro is noticeably heavier than the Triton, but with the placement of the battery pack at the rear of the helmet it feels well balanced. As expected, with the battery in the helmet the Airshield Pro is a bit noisier than the Triton, measuring 84.6dB. Air flow, which is rated at between 5.6 (minimum) and 7.06 (fully charged) cubic feet of air flow per minute, is noticeably stronger than on the Triton. Twin filters are rated at 98% efficiency, but are not NIOSH N95 rated.
The visor has also been moved closer to the face to improve the field of vision; eyeglasses end up being quite close to the visor. Like the Triton, the visor is very clear, with little visual distortion. To protect the visor from scratches, Trend offers a plastic overlay with adhesive edges that is simply attached over the visor. When the overlay is scratched or damaged, it is simply peeled off and replaced and at a cost of around $4, which is considerably less than the cost of replacing a scratched shield. Unlike the Triton, ear muffs are an optional accessory on the Trend Airshield Pro. The helmet also uses a ratcheting adjustment knob at the back of the helmet to adjust fit (you need to press on the knob to lock it in place). While on the Triton you can move the visor away from the helmet, on the Airshield you tilt the whole helmet shifts upward out of the way. There is a small removable shroud that wraps around the bottom of the helmet and sits just above the ears. It doesn’t do as good a job as the Triton in sealing off the entire head from dust, particularly around the ears. You can wear glasses under the helmet, but the fit is somewhat tight, particularly along the side of the head. The Airshield Pro, which has a one year warranty, has a lot to recommend it, particularly its removable battery and higher air flow rate.
These powered face shield respirators are the perfect solution for anyone that is involved in a dusty and noisy operation. Woodturning is the type of situation where these tools really shine and show their worth; they have become a favourite of turners for a very good reason. Turning a bowl or spindle generates a considerable amount of shavings and dust, and at times this will be directed right at the turner. Standard safety glasses will not protect the worker from flying debris that can come around the sides of safety glasses, and they will certainly not offer any protection whatsoever if the bowl should be released from the chuck accidentally. When a bowl comes off it can cause considerable damage to whatever it contacts. This can happen without warning and turners should always wear a full-face shield. The fresh air flowing over your face will keep the shield free from condensation as well.
When standing at a lathe, holding your head more or less in the same position, the weight of these shields may become fatiguing during prolonged use. Users will need to take the added bulk of a powered full-face respirator into account when working in confined locations. Wearing either of these products takes some getting used to and looking like a member of your local Hazmat team, you’ll certainly get a curious look or two should anybody drop by for a visit.
Powered face shield respirators offer the woodworker a final line of defence to protect their sight, hearing, lungs and good looks. Whether you are turning a bowl or grinding and cutting concrete, these systems are your ideal safety solution. Neither of these units are cheap, but when stacked up against a trip to the hospital and the potential damage an accident could cause, it only makes sense.
Powered face shield respirators are not designed to be used in areas containing explosive vapours such as paint spray booths.
If you don’t think that a powered full-face respirator is what you need, you might consider a standard, non-powered respirator, like the 3M 6800 ($154.25, from acklandsgrainger.com) or the North Safety 5400 ($171.77, also from acklandsgrainger.com). In appearance and function they are quite similar products. They are very light weight protectors (approximately one pound) providing a wide field of vision and impact resistant visors . Both feature soft lightweight face piece shields made of a pliable elastomer material, easy to adjust head straps, and come with peelaway visor covers. A nasal piece on the front of the mask contains a one way flap that emits humid breath (helping to reduce visor fogging). On the 3M the nasal piece is removable for easy cleaning. These respirators are very comfortable in use and the N95 rated filters offer excellent levels of protection from fine dust. The dust cartridges on the 3M have a three point connector, while those on the North Safety screw on. Unlike the conventional paper dust masks, that tend to be used a few times and then chucked away, the filters on these masks last quite a bit longer before having to be replaced. Hearing protectors fit comfortably over either of these respirators. We tried both respirators in the shop and found that they performed admirably. They aren’t as comfortable as the powered respirators when used for long periods of time, particularly in hot or humid environments, and if you wear glasses, the fit will be bit tight against the temples. However, we found it much more convenient to slip on a full face respirator than having to search around for a dust mask and eye protectors. And, you can buy a range of different filter cartridges for different applications (organic vapours, gases and the like).