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Few contractors choose to work at night, but those who do make sure they are well prepared. By Paul Hull |
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Contractors who enjoy night work form a very small minority. Many contractors - in just about every state - seem to avoid night work if they possibly can. It's not that the law says they have to pay higher wages to their employees for night work because they don't. Nor is it because they are simply afraid of the dark. The reasoning behind the hesitation to do construction work at night is that everything is more difficult to do accurately, and productivity - along with profitability - seems to be lower. "We do no night work - never consider it," says the owner of a small construction company in Michigan. That blunt comment sums up the views of many professionals. Some were even more candid. "You'd better make special preparations for night work and try to find somebody who still does it," comments a retired engineer from northern California, whose main responsibility for many years was estimating projects for municipalities. "The main risk is that you may kill someone; the other [is] that your productivity goes to hell, and you lose your butt!" Some contractors, on the other hand, do night work regularly. "As long as the documents outline the project requirements, we have few problems with accepting night work," says Ted Robinson, vice president of estimating at JM Olson Corporation in Saint Clair Shores, MI. The company is a leading contractor in Michigan, with more than 2,000 employees and awards for a variety of prestigious projects. "You have to calculate accurately the costs of overtime, lighting, keeping your plants open, safety, and loss of productivity. If there are reasons for inexperienced contractors refusing night work, they would be not understanding the requirements, having key staff unwilling to work at night, and lack of experience." Steve Ikenaga at R.M. Towill Corporation (Hawaii's largest engineering firm, with 100 staff members and projects that have included the Mauna Lani Resort, the Hyatt Regency in Guam, and the Queen Kaahumanu Highway) makes several interesting points. He confirms that the noise issue could complicate or prevent night construction work and advises that parties potentially involved should investigate adequate safety measures, such as warning lights, police involvement, use of reflective materials, and other lighting. He also mentions public awareness of any night project, via published notices, informational signs, and community meetings. "I would imagine that worker safety and driver safety are key concerns for people with opportunities to bid on night work," says Ikenaga. "We are engineering consultants, and the liability issues associated with worker/driver safety have not directly extended to us, although I wouldn't be surprised if they eventually do." He reports that he is not aware of any local contractor who has refrained from bidding on night work when it was otherwise appropriate. Another Side to the Story The customer (public or private) wants the work done as soon as possible. The contractor wants to complete the work and get paid. There are times, however, when construction work is not convenient. We all hear the question "Why can't they do this when there's no traffic?" for highway and street work. We all know that the same people resent noise and disturbance when the street work is done during the hours of least traffic: at night. Their reasoning is understandable. When residents feel entitled to enjoy the peace and quiet of their homes, engines and machines should be silent. It seems universally accepted that those rules are changed or suspended during an emergency. "Sometimes we have to secure buildings at night," observes Paul Young, a contractor based in Billings, MT, who manages projects for the repair, protection, and renovation of structures damaged by flood and fire. "We have good lights and the right equipment and tools available if we have to board up windows - even place tarpaulins over damaged roofs - anything to prevent unwanted access by weather or people after there has been a disaster at a property. We don't do much work at night, but we are always ready for it."
"Night projects create noise, light, and traffic impacts," notes Joseph Fessler, a civil engineer with Hedges Engineering & Consulting Inc. in Buckley, WA. Much of his work concerns development engineering for a municipality. "These impacts could be problematic for local residents and initiate complaints. You must notify affected residents before the work begins. Truck routes to and from the site should be reviewed and modified to minimize the impacts." Many communities have regulations about when you can do construction work. William Moore, an engineer with the City of College Park, GA, notes that his city enforces code regulations stipulating that construction work must be done between 7:00 a.m. and 10:00 p.m. in residential areas. "The most compelling reason not to do night work is if it is in a residential area," comments Jim Somers, an employee of Sarasota County Public Works in Florida. "Other factors that should be considered are safety, workmanship, possible utility damage, and the ability to make repairs. The contractor and the owner should also consider testing and inspection capabilities when the project is done at night." Somers goes on to say that required special preparations might include media notification, variable message boards and signs, fliers to impacted businesses and residents, and adequate maintenance of traffic. "A contractor may be reluctant to bid on a night project, especially one of long duration, because of staffing difficulties, loss of efficiency, and daytime workload," observes Somers. Regarding whether or not contractors who undertake night work continue their normal daytime schedule too, no conclusive evidence is available. Would you hire extra employees for a night job, perhaps workers who have nighttime experience? Would your regular crew do the night job and not work in the daytime? Would they want to do that with no extra compensation? Ask the proverbial man in the street what he would dislike about night work, and his answer probably will reflect the inconvenience of working when he could be relaxing, watching television, being with his family, going out with his friends, or sleeping. That man in the street is not just lazy or uninspired. The inconvenience of working at night might be harmful for several reasons. To say "it just ain't natural!" seems a feeble excuse, but it is true. Whether it is a result of the thousands of years of history - especially with the vast majority of them occurring before the use of electricity - or whether it is some kind of natural defense, the average human body prefers to work in the daylight and sleep at night. Good Sleep Might Conquer Most Problems Sleep might be the key. Night workers sleep during the day when there are more noises and outside activity, and research has shown that daytime sleep is likely to be lighter and shorter than its nighttime equivalent. Look up the term circadian rhythms if you want to read some expert information about this; the term does not refer to Russian dances or psychic forecasts. In terms of whether he sees many effects of working at night, a doctor who works in the emergency room of a hospital in Montgomery, AL, mentions that he has no recorded evidence of a greater-than-usual number of construction workers being injured, but he notes that one of his physician colleagues has learned from reliable research that staying up all night has the neurological dysfunction equivalent to four or five drinks of hard alcohol. The doctor investigated the subject when he thought his own driving was less efficient after a night at the emergency room. When a worker has inadequate sleep, he or she is likely to lose concentration on the job. It might be only for seconds, but how long does it take to do damage with an excavator? Concerns about safety for people and structures should be much greater when the operator of a grader or an excavator lacks proper sleep. Most of the health dangers listed for night workers are for those who work frequently and consistently at night. They apply much less to those who have to work two nights every three months or six nights in a year for a special project. Most night work for contractors tends to be in short doses (except for those big highway and street projects that some public authorities do not allow during the busier daytime), so fears about excessive damage to workers' health need not deter you from undertaking them. From what we have learned, the occasional night or two at the construction site will not destroy anybody's balance. Good Lighting Is Essential; It's the Law In 1894 the City of Austin, TX, ordered 31 towers - they became known as the "moonlight towers" - to illuminate the city at night. Some of them still are there today, although most have been moved to make way for new sidewalks or street widenings and show such understandable signs of age as rust. They were made of cast iron and wrought iron and were very heavy on their immobile pedestals. The criterion for those early light towers was that "time could be seen with an ordinary watch in the darkest night." Today's light towers are lighter and mobile and have much better directional capabilities. There are national regulations about the lighting used for construction work at night; they are set by the Occupational Safety and Health Administration, and they are not optional. Read and understand them at www.OSHA.com. At some projects, an inspector will be on-site to see that all of the appropriate lighting rules are followed. That makes sense, doesn't it? The main difference between working during the day and working during the night is the light. Seeing what you are digging, moving, or adjusting is essential for accuracy and safety. There is a good selection of lighting systems available, suitable for large, football-field-sized sites or compact, between-the-houses jobs. One reason why night work is banned in some places is that, of course, apart from any noise of machinery, the bright emergency lighting would disturb the neighborhood. Have you ever found yourself in a motel where the flashing light from the motel opposite - does it have to be bright pink? - seems to go on all night?
Experience tells many contractors how much light they need for night work, but there also are guidelines for the uninitiated. One supplier of light towers is Amida Industries (a Terex company). There are some interesting, practical data on the company's Web site to help potential buyers select the best system - one that supplies what is needed but not too much. Quoting from a publication of the Illuminating Engineering Society, a chart on Amida's Web site says that recommended levels of illumination (measured in foot-candles) would be 10 for general construction, 2 for excavation, 20 for loading and unloading, and as high as 50 for some recreational or sports applications. You also can see how to calculate the recommended lighting for particular sites. Information, such as that from Amida Industries, also is available from other manufacturers and their distributors, among whom are Ingersoll-Rand, Genie, Sandhurst, Reva, Hawkpower, Wacker, Will-Burt, and Coleman. You also can learn the advantages and disadvantages of different light sources. High-pressure sodium (HPS) offers several advantages, including low depreciation (rated average life of 24,000 hours) and fast restrike, but has a high initial cost. Metal halide has a lower-rated average life and is recommended for its overall lighting capability but has a long restrike time. Mercury vapor offers the same long life as HPS; it is vibration-resistant and has a fast restrike time. Its lumen output is lower, with high lumen depreciation. A tungsten-halogen (TH) light source offers the lowest initial cost, has a natural daylight color, and instantly turns on. It provides good control for aiming the light and has very low lumen depreciation (because its lumen output is low). A disadvantage of TH is its high surface temperature and short lamp-life expectation. Among the many questions you might ask your supplier about a proposed lighting system, some are presented here. Is the system towable? Does it transport well and undamaged across rough terrain with severe vibrations? Is there an outrigger system for uneven ground? How long will the light run continuously between fueling pauses? How high do you need the lights? Are there circuit breakers for each light? Will you have horizontal and vertical adjustment at the site? Is there a tilt function for directing the lamps from ground level? How good is the power-cable system protection? How secure from vandals is the lighting system? Will the battery start the system in cold weather? What do light-tower manufacturers stress about their products? Among Multiquip's wide range of Night Hawk light towers are the LT-12D and LT-12P. The maximum mast height is 30 ft. for each, and it rotates 360°. Despite their light weight, the LT-12D and the LT-12P have shown themselves to be sturdy enough for work in gusty winds. Their fuel tanks (30 gal. each) will provide a continuous run of 64 hours. "Separating the Night Hawks from competitive models are internal lights that illuminate the light-tower cabinet and two exterior receptacles that allow the operator to power small tools and equipment without opening the cabinet doors," notes Peter Cannon for Multiquip. "The generator on each light tower boasts a continuous output of 6,000 watts and noise levels of 73 decibel-amps at 23 feet." Lights don't just replace the sunshine and help your crew members see what they are doing. There are lights to tell people that you are there, working. Reva, for example, offers the Visi-Flash barricade lights for traffic control. The lights meet or exceed all federal and state lens specifications, as well as standards published in the Manual on Uniform Traffic Control Devices. The Visi-Flare is similar. It operates for about 18 hours on two D-cell batteries (8 hours if you use C-cell batteries). It has a history of success not only with police and fire departments but also with utility workers. Bystanders, Beware! There's always somebody to watch you work, isn't there? Even in the middle of the night, there might be onlookers at a site. According to more than one contractor, the people who hover around the site at night are less desirable than daytime viewers because nighttime viewers - often unable to walk a straight line or enunciate clearly - are more likely in no condition to observe today's construction methods. Whatever preparations you make for your workers, remember that site security is essential at night, for your workers and any visitors.
One of the reasons some public projects are commissioned to be done at night is that night shifts tend to be longer, with fewer interruptions from traffic. That means a job can be completed in fewer days with night operations than with a daylight schedule, and this appeals to public authorities. Traffic, however, is one reason why some contractors do not bid on night work, especially work in streets or on highways. They believe that too many drivers travel faster and are less cautious at night. The high percentage of nighttime accidents involving alcohol or drugs in work zones seems to reinforce that theory. If your night job is in a zone that has significant night traffic, consider having traffic-control persons on duty. Visibility still is the key. Workers should wear clothing with retroreflective material. The clothing should be visible from all directions so it protects the wearer no matter what he or she is doing. You want reflection that shows even when the worker bends down to adjust a tool or turns around to listen to the foreman. There is a reverse side to this visibility aspect of night work. Operators should try to ensure that the lights from their machines and the tower lights do not blind motorists or truck drivers. Your state might have specific rules about job-site lights; you should be aware of them before starting. Machines Do Not Know Excavators, loaders, graders, and dozers don't know if it's day or night. They function as well in the dark as they do in the sunlight, although it might not always seem so to the unprepared operator. It's not difficult to mount lights onto an earthmoving machine; many of today's models arrive with them already installed. It might be more difficult to remember to inspect and service a machine before it does its night duty, especially if it has been working all day. For a machine, the night shift is exactly that: another shift. It wants lubrication and greasing according to the manufacturer's recommendations. Its tires need inspection. You wouldn't think of starting the machine for its night work without checking the fuel in the tank. That fuel is useless if any other function isn't as it should be. Did we mention the tires? "One solution to coping with some problems posed by night work is the use of machine guidance systems," notes Mark Sprouls, a correspondent with considerable experience working with mining experts, whose work is mostly in the dark. "A system like Caterpillar's Computer Aided Earthmoving System for tractors, loaders, shovels, and motor graders offers a display map in the operator's cab that guides him in low-visibility situations. The problems can be caused by darkness, blowing dust, rain, or fog." Caterpillar now offers the AccuGrade laser grade control system, so far for its D3G, D4G, and D5G track-type tractors, that uses no traditional stakes or grade checkers (who would face obvious hazards at night). The manufacturer says this system will provide significant productivity gains in such applications as finishing multiple residential pads. A beeper and colored lights indicate the blade's position relative to the desired grade. Enhancements for machines are available from several manufacturers. When you consider night work, then, investigate how your actual machines can help the operators be more productive and safe. Working at night can be safe and most profitable if you make the right preparations for people and machines. Paul Hull writes on construction and environmental topics for several international magazines.
GEC - March/April 2004
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