AIEL Shop Tips
AREA and TASK
LIGHTING
Worklighting is an often neglected facet of equipment
maintenance. Proper illumination allows for comfort
and ease of service. Following these procedures will
provide necessary light levels without distracting shadows.
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INFORMATION BELOW MAY |
Be aware neither Atlantic Illumination, nor its owner |
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Read through this article and decide what lighting your shop might require. You should also peruse other articles in the Work Area Setup to decide what lighting to install for specific areas such as benches and work stations, and to think about how you plan to power it all. In particular, do this in conjunction with what is discussed in Work Area Design so that your shop layout will be known before installing lighting. The methods below will assure good worklighting. They relate to a medium-size shop with multiple work areas and benches. Scale this up or down to fit your workshop size and needs. |
Circuits: Overhead shop lighting must be on a separate circuit whenever possible. This is so that if you trip off a bench, station or wall outlet breaker while working, you won't lose the lighting and be in the dark. Try to locate the breaker panel within or close to your shop for the purpose of convenience. Label outlets and light switches with the numbers of the breaker panel and breaker so as to allow you to go directly to the breaker that has shut off.
Circuit amperage capacities need to be decided upon based on the likely power to be consumed. Typically, lighting circuits will be 15 amps, while bench power should be at 20 amps, or even a split 20/20 amp double breaker. Thus each half of a typical duplex outlet will be able to supply 20 amps of current. To comply with Canadian electrical code, the duplex outlets installed must be rated at 20 amps.
Wiring methods and the wire type and gauge must
also comply with your electrical code. See
Work Area Power for a basic discussion.
Locate switches for general shop lighting at the entrance to that shop. For specific lighting next to cabinets or stations to be illuminated, and for task lighting, their switches should be placed near each particular bench but not too close to the actual bench top. Using individual switches for each location allows for lower power consumption because only the general area lights are turned on until you begin to work at a particular station or bench. Then, only those lights need be on while the others remain dark. Again, Work Area Power will supply more details.
Consider placing two-way switches where personnel might enter from more than one direction. This way, one need not have to walk through a dark area in order to switch on lighting. Conversely, one need not have to switch off lighting and walk out through a dark area. The latter situation often results in lights being left on needlessly.
Think about using illuminated switches, or ones with indicators that light when the switch is off. Some also indicate when a switch is on, but these are only really useful when there are gangs of wall switches, yet are unnecessary for most shops with one or two switches together. These "off" indicators will define the location of light switches in the dark.
If using such indicators for both off and on, get the type that show the actual status of the switch -- that is, red when off, and green when on. Be wary of those that show the indications the other way around! Some stupid designer who never uses such switches must have thought of this one. DUH!
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Caution: You should not have to lean over your work to access the switch, nor should you be able to accidentally lean on the switch while working. Contacting a grounded, metal switch box or plate would be dangerous should you happen to touch live current at the same time. |
Area Lighting: Consider the fixtures for general shop illumination. These will be the ones placed above work and storage areas at, or near, ceiling height. T8 fluorescent sources are recommended for this as they provide soft, wide, even illumination; plus they consume less power and generate less heat compared to an equivalent amount of incandescent sources.
If you can budget for T8 LED fixtures, these will consume even less power for a given light output than incandescents and fluorescents. Be sure to see a demonstration of the intended LED lights so that you can choose fixtures that will provide a smooth, wide-angle light that is not too bright for your shop.
Colour Temperature: Choose a fluorescent or LED lamp colour temperature of 3000K for your general lighting. These will emit a warmer light than office-white or daylight sources, thus providing a more pleasant atmosphere within which to work. Also, this temperature will blend well with the incandescent task lights as is discussed near the end of this webpage.
Positioning: Hang fixtures to either side of the work space so as to eliminate shadows. Usually, two twin-tube fixtures with T8 lamps are sufficient. Since our benches and their adjacent areas tend to be long and narrow, we use twin-tube, tandem fixtures where the lamps are end-to-end to one another as opposed to being side by side.
If the ceilings are high, you may have to upscale to four-tube fixtures, or to lower the fixtures on chains to be about three metres above the bench top. Use industrial fixtures which have curved-down reflectors. These concentrate the light downward and give some measure of shielding of stray light. The reflectors can be eliminated if light to the side is required to illuminate shelves near ceiling height, as is needed in our shop.
The outside edge of each fixture should be just above the outside edge of the bench. If the fixture is too far away, your work will be shadowed when you stand between that fixture and the bench. If the light is too far over the bench, the work itself will cast a shadow toward its own outside edge, plus glare from the fixture will encroach upon your field of vision. Should the shop area be wide, you may need to mount more fixtures to provide enough lighting for the floor area away from the benches.
Cabinets: For any desk or countertop that has cupboards above, under-cabinet lighting should be installed to illuminate that surface. This style of lighting is the solution for shelves situated under pallet racking, as well. These fixtures are screwed into the wooden pallets just above and forward of the area to be illuminated.
Fluorescents work well for both situations as they provide soft, even illumination, although diffused LED strips are making inroads for this purpose. The latter consume the least power and generate the least heat compared to almost all other light sources. The length of either is perfect for long runs of countertop or pallet racking.
Commercial units are available. They are slim and easily mounted, and come with one- to two-metre line cords that plug into handy outlets. We install ours so that the fixture is as far forward as the above cabinet allows, and with the lamps facing the back wall so that no glare is emitted forward; thus the lighting is on the work at hand.
If side-shining lighting is a requirement, one may use a strip light. These are less expensive but don't have diffusers or wide reflectors, and some have no line cords. We have employed these types of fixtures for some purposes, mainly under pallet racks. Besides the cost saving, we can wire up any length cord to suit. Since there are no diffusers, these are always used where they can be mounted into a cavity to prevent spill from emanating. Wherever this can't be done, black foamboard is cut to mask the bare tubes and glued to the front of the fixture or to the pallet cross-beams.
Sinks: Above a shop sink, one might hang an R30 or R40 floodlamp. These give a bright, direct focus of light. However, they do emit heat and so must be protected from splashes onto the hot glass to prevent shattering. If using this source, mount the light up high away from splashes, or enclose it in a water-proof globe.
Alternatives would be a weather-rated PAR lamp because its harder glass can withstand water without breakage. Or, give up heat altogether and use an LED PAR. Both PAR types have a tighter focus than an `R' lamp. We have selected the LED lamp so that the fixture can be mounted closer to the work.
Typical wattages for a sink purpose range from 65 to 120 watts for R lamps, or PAR lamps from 50 to 90 watts. LED equivalents will give the same amount of light for wattages as low as 4 to 10 watts.
Specific Bench Lighting: Next, we look at task lighting. This is the lighting at each bench and station that will be focused directly onto the work at hand. The recommended fixture here is the swing arm type as illustrated at the left. This is ideal because it is adjustable in all axes, has a long reach, and can concentrate light exactly at the angle required. These fixtures can actually be brought right down next to your work as needed, yet swing out of the way when not wanted. They mount with a clamp or via a base that is screwed onto the bench, a post, or a wall.
Suggested Lamps: Use 65 or 75 R30 flood lamps with well-diffused bulb faces. Do not use ordinary 60 or 100 watt light bulbs. These typically don't put as much light on to your work as an `R' floodlamp, and they will heat the swing arm's reflector to a point of being able to burn skin. This is not desirable when the fixture has been placed close to the work so as to illuminate some inaccessible area. Should your face touch that reflector, you would prefer it to be cool.
Alternative Reflectors: There are swing arm fixtures available that place the reflector inside the outer housing. It is separated from that housing so as to limit heat transference by isolating the outer surface from the hot reflector. These are fine to use, but will cost more. Regardless, it's still recommended to use the `R' lamps because they output much more light per watt.
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Cautions: Realise that fixtures using `R' (and PAR) lamps run at a cooler temperature because they project most of their heat out the front of the bulb face. As such, one must be careful that they are not focused closely upon heat-sensitive objects such as plastics, heat-shrink tubing or electronic components. In addition, do not use CFLs (Compact Fluorescent Lamps) as a light source. If one breaks during work because it gets hit, toxic mercury-laden dust will spill on to you and work surfaces. Plus, these lamps rarely fit swing arm reflectors well, so they spill light into the eyes. |
Placement: There should be two swing arm fixtures mounted, one on each side of, and higher than, the immediate work area. From a stationary, central position in front of the bench, a worker should be able to reach to either fixture for adjustment. Thus, unless the bench is not very wide, they will end up inboard of the bench sides.
Attach the fixture mounting blocks near the back of, and about a quarter-metre above, the bench. Doing so will permit tools and accessories to be placed outside of the main work area, and allow the fixtures to be brought down over top of the work right next to any side of it. There will be no interference to the arms from the sides or from the work piece itself because the lights have been mounted far enough back and high enough up.
Designating Separate Bench Work Spaces: If the bench is long, consider dividing it into two or more work positions. Each would have a set of swing arms, one on either side of each space. Duplicate the tools at each for the usage of two repair techs, or designate each space for a different type of work. (We have done this; see the bench photos in our AIEL Shop Photo Tour.)
Task Light Power Source: swing arms may be plugged into bench power if the overhead lights are on a separate breaker. Otherwise, try to draw power for the bench swing arms from another circuit. This is to prevent a total blackout should you trip a breaker while servicing electrical items.
Other Locations: Place swing arm fixtures at places such as a drill press, glue-gun station, paper-work/computer desk, parts cabinet, buffer station, or anywhere extra light is required that must be directed toward something such as parts drawers, or kept away from something such as a computer screen. These will likely only need one fixture each. However, if you find yourself constantly moving a single fixture in order to better illuminate a given location, then install a second fixture so as to light from two angles.
A Final Word: Since incandescent task lighting has been specified along with the fluorescents and LEDs, it has been suggested that 3000K colour temperature tubes and LEDs be used. The reason is not only for a more pleasant workshop look, but also because they have a colour temperature that is close, or equal, to typical incandescents. This is important regarding the reduction of eye strain. If one must look back & forth from an LED or fluorescent white area to a more amber incandescent area, it tires the eyes. The colour temperatures of the lights should be as equal as possible to maintain smooth transitions from one surface to another.
You now have a shop with brighter task
areas and a much more comfortable atmosphere
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