Grading and Excavation Contractor

Many contractors do not seek night work, for good reasons.

By Paul Hull

From most of the conversations we have had with contractors and public authorities across the country, the two main worries about contracts for night work are the safety of everybody involved and the quality of the work done. A good point made several times was that most workers do not like working at night for health, family, or safety reasons, and that can mean the workers you hire for that night project are possibly not the most skilled for the kind of work that needs to be done. Like all comments about night work and night workers, these are generalizations, but they have been made often enough to carry good weight in an argument. Even if you ignore the value of an excavator itself, do you want an inferior operator to run it, in poor lighting conditions?

Safety is the major concern. That is good, isn’t it? The owners of contracting companies we spoke with did not mention the safety of the equipment and its possible loss before the safety of their workers. That’s good, too, isn’t it? Many contractors don’t even consider night work, except for emergencies. At Lone Star Excavation in Flower Mound, TX, where Bob Asplin is president, they do mostly residential and commercial work—building pads—and there is never a need for night work. In Barre, VT, there are very few night projects for a grading and excavation contractor. “We don’t see any bids,” says Mike Pitonyak, owner of Capitol Earthmoving Inc. “I think all the night work must be in government contracts.” Michael Hagen’s Hagen Grading Co. in Sioux Falls, SD, does mostly commercial and residential work, and there is no call for nighttime work on his projects. At the other end of that state, in Rapid City, RAJ Rentals & Equipment rents backhoes and loaders frequently. “We have no call, however, for that equipment for night work,” notes Denny Erickson, manager of the store. “All the night work seems to be done for road construction, requiring bigger and more specialized equipment than we have.”

Photo: Ingersoll-Rand

Experience will teach you how many lights you need for a particular project.

Implied in many responses was the fact that night work is usually done by bigger contracting companies rather than by those thousands of small contractors who comprise the majority of our sector. There is a perception that undertaking work at night may require extra equipment. Renting special equipment for the occasional nighttime project seems to be the most popular solution but only when the anticipated profitability of the job permits it. “We do work on parking lots and city streets, nothing like interstate resurfacing,” comments Dick Johnson at Asphalt Surfacing Co. in Sioux Falls. “We have not done night work. The traffic hazards increase dramatically and the danger factor goes up in almost every aspect of the job. We would not like that for our employees. You have to question if the quality of work would be as good, too, in artificial light.”

Why Are There Nighttime Projects?
Who wants work done at night? By far the majority of contracts mentioned were from federal or state sources, and most of those concerned road construction. “We have seen lots of night work,” comments Chris Boland at United Rentals in Chantilly, VA. “It is mostly road construction, state or federally funded, and we get the impression that it is going to increase this year.” United Rentals will service its customers 24 hours a day, explains Boland, but the contractors get their equipment for night work during normal business hours. They plan their work, decide what they need to rent, and get it in advance of the actual arrival of nightfall (and the closing of the store). Across the country, at United Rentals in Glastonbury, CT, Manager John Buske comments that he has had little demand for grading and excavation equipment for night work. “Most of the work seems to be paving, and the big contractors have those machines already,” notes Buske. Hubbs Contractors in Camden, TN, has successfully completed many road construction projects. “We’ve never done the construction at night,” says Chris Buckingham, vice president at Hubbs. “And, yes, the jobs that require night work always seem to be state or federal contracts.”

Is there an alternative to scheduling road construction work in the dark hours? “We are looking at a system called Merge Left that has been successful in Arkansas,” notes Kent Starwalt, executive vice president of the Tennessee Road Builders Association. “People don’t like road construction at night because of the safety hazards involved. One great concern is that there is an above-average percentage of drivers under the influence of alcohol or drugs at night—more, we are told, than in the daytime.” That has to be a concern for anybody working at night at any site, not just along the highway, but downtown, on Main Street, working by the high school or near the shopping mall. We get used to people watching us work and even tolerate those who like to give expert advice on a better way to dig that hole, but if you add the innate dangers of alcohol and drugs to the person hovering around your site, it’s difficult to concentrate.

If there is a sense of annoyance about the apparent probability that night work projects will increase this year, it is because contractors feel that the main reason for jobs in the darkness is “purely to avoid inconvenience to the public.” That seems especially true of road construction. There are ways to keep the traffic flowing well past a closed lane—that Merge Left principle mentioned above is one of them—and several contractors are questioning if the dangers to people during night operations are worth the risks.

If there were no night construction, how long (in daylight) would it take to feed a single line of traffic where there are normally two lanes? If you find a method of stopping those drivers who cause much of the congestion by hopping into the only lane at the last second after speeding past everybody else trying to do the right thing, the traffic would flow freely. Even with slower speeds past the machinery and workers, going through the project in single file takes far less time than drivers imagine … especially in the daytime. So, an aspect of the night work scheduled that has been seldom addressed recently seems to be turning up more frequently. Why should we have night work? What if qualified contractors don’t want to bid? Is doing the work only at night, for the public’s convenience, justification for having it done by less-than-qualified contractors? One of the anomalies of public feeling about construction is that it should be done at night on the streets and highways (because people don’t want to be inconvenienced) but never at night in one’s own neighborhood (because people don’t want to be inconvenienced).

Photo: Multiquip

Loss of Quality
Medical research points to the fact that people who work at night may suffer from lack of concentration and tiredness to a greater degree than those who work in the day. It is to do with a system in our bodies called circadian rhythms. (Not Circassian Circle—that was a country dance I did in elementary school and pretty Patricia Welfare was my favorite partner.) Our bodies have these circadian rhythms that affect our daily disposition; they influence our body temperature, heart rate, blood pressure, and hormone levels. They can even dictate how well we accept pain. We are most likely to sleep best when our body temperature is lowest, usually in those fabled wee small hours of the morning. As we grow older, our circadian rhythms seem to change, and we tend to have interrupted sleep, we feel inclined to nap more often and wake up earlier. This is not the place for a study of these body rhythms but you can find interesting facts about them on the Internet. They do indicate that, for most people, working at night is not a natural thing to do.

We found no evidence from emergency rooms that construction workers were involved in an abnormal number of accidents but one report was most interesting. “I have several years of practical emergency room experience,” notes Dr. David Spiro, at Yale University in Connecticut. “I remember one of my colleagues, in Alabama, determining from his research that staying up all night caused neurological dysfunction equivalent to four or five drinks of hard alcohol. He realized that when his own driving skills were clearly less efficient than usual after a night spent working the emergency room.”

When a worker has inadequate sleep, it is probable that he or she will lose concentration at the job site, whether that is in an office or in a loader or dozer. The loss may last only a second or two. How long does it take to damage an excavator or slam a bucket into a utility? Mrs. Baker of Baker’s Excavating and Septic in Dowling, MI, makes the point that artificial lighting is good but it’s not daylight. Precision and quality of work would be her concern. One example she gives is from contractors who worked at night and told her of the difficulty of seeing dark earth walls that were starting to cave in—not in trenches, because they would be shored, but in larger areas. The sleep may be inadequate because the night worker is sleeping during the day when there are more noises and more interruptions. Daytime sleep usually lasts a shorter time than “regular” nighttime sleep, too.

Photo: Mobillight

Among the less mentioned disadvantages of daytime sleep is that it removes the sleeper from the normal pattern of family or social life that others follow. The night worker may see his family rarely. He may hardly ever meet with his friends, because they are working when he is asleep and he is working when they are ready to enjoy themselves. The social problems caused by consistent night work should not be ignored. Did you notice that we said “consistent” night work? It seems true to say that the occasional night on the job will not harm somebody in the long term. Nobody objects to night work if there is an emergency, however noisy the machines or bright the lights.

Turning Night Into Day
The most obvious disadvantage of working at night is that you cannot see what you are doing. That applies equally to small and large jobs, to using a hand tool or directing an excavator. For this reason there are local and national standards for lighting at construction sites. You should know what they are if you are going to do any night work. Your best source for helpful information may be the OSHA Web site (www.OSHA.gov) but don’t forget to check with local authorities, too. If you have never done night work, it may be helpful to ask contractors who have experience, because they seem to understand how much light is needed for certain tasks. They also know who can supply the best lights for your project. They can tell you that, if your grading or excavation is along a street, a couple of trailer-mounted lighting systems may be adequate, because you can haul them along as the work progresses. Most of your loaders, excavators, and graders already have lights installed, because there are so many occasions when even the daytime light isn’t as good as you’d like for accurate work. Most experienced operators tell us that they are consciously more careful—and likely to be just a little slower—as the sun goes down, when there is dust in the air, or when heavy clouds obscure the sun. The machines themselves do not know if it’s night or day, so it’s up to the operator to guide them; their functions are as good in the dark as they are in the light.

Photo: Amida-Terex

The LightSource portable light tower from Ingersoll-Rand could be useful. It includes a 6-kW generator that can operate four, 1,000-W, metal-halide or high-pressure sodium floodlights for up to 68 hours of continuous operation. The standard metal-halide floodlights give a NEMA 6-beam spread; that gives good distribution of light and coverage for a good area. The steel tower of the LightSource is a three-section mast that extends 12 to 30 feet, with the mast raised by either dual, hand-operated winches or optional electric winches. How safe is a mast 30 feet high with lights on it? At full mast extension and with all four outrigger/jacks secured, this model can withstand winds up to 65 mph. For precise targeting of the light, you can rotate the tower 360 degrees and lock it into position. The LightSource is a towable unit. It is placed solidly on a 3,500-pound axle, with a standard 2-inch ball hitch and two-light towing package, side markers, and reflectors. It meets US federal and Canadian Motor Vehicle Safety Standards.

Also from Ingersoll-Rand, another lighting unit caught our eye. This is the BL2000 balloon light. It is a self-inflating unit—a balloon light—that diffuses a strong, glare-free light over a 360-degree area. With an optional mounting system it can be 15 feet tall. It covers up to a 15,000-square-foot radius. The BL2000 can be set up on its optional stand or affixed directly onto a piece of your equipment. It inflates in less than one minute and can resist wind speeds up to 63 mph. With a weight of less than 40 pounds, this lighting unit can be carried to and from the site in your car.

Another leader in light towers is Multiquip. The company has some called Night Hawks. The latest in the series are the LT-12D and LT-12P. Maximum mast height is 30 feet and they rotate 360 degrees, with stability against winds up to 65 mph. They offer four metal-halide floodlights, a 30-gallon polyethylene fuel tank that provides 64 hours of continuous run time, plus the safety of high-temperature and low-oil-pressure shutdowns. You can use either a 12-horsepower Deutz or 10.7-horsepower Perkins diesel engine. Among features that Multiquip says place these models apart from others are internal lights that illuminate the light tower cabinet and two exterior receptacles that let the operator power small tools and equipment without opening the cabinet doors. The generator on each light tower has a continuous output of 6,000 W and noise levels of 73 decibel-amps at 23 feet. For transportation there are forklift slots and 2-inch ball hitches. A standard flatbed truck can hold eight of these Night Hawks, with each model weighing 1,550 pounds. You might also ask Multiquip about its modular light towers, for which the operator can change tower, lights, and power source in just a few minutes.

Terex-Amida has an optional automatic start/stop feature on its AL 4000 automatic, portable floodlight system. It means a user can get around that time-consuming job of manually controlling a group of light towers. There are two modes. The first is a timer mode that, when set, turns the generator on or off at a particular time. The second mode is the photocell mode; that signals the tower to turn on or off based on the amount of natural light surrounding it. The AL 4000 has a 30-foot reach at its full extension. A winch eases the raising and lowering. The tower rotates 360 degrees. This light tower offers four 1,000-W halide lamps that can illuminate up to 7.5 acres, or provide isolated lighting for nighttime job sites. Its 30-gallon fuel tank allows the 10.5-kW Kubota diesel engine to run continuously up to 60 hours. And it’s quiet—71 decibel-amps at 23 feet.

Photo: Sportlight Products Inc.

What Are All These Names for Lights?
For light towers that allow contractors to do night work, there are four basic light sources. We thank Terex-Amida for these helpful data. You can find the information in a chart at www.amida.com. High Pressure Sodium (HPS), Metal Halide (MH), Mercury Vapor (MV), and Tungsten Halogen (TH) are the four sources. One will probably be right for your application. Each offers 1,000 W per floodlight, except the TH, which gives 1,500 W. The rated average life for each type follows: HPS, 24,000 hours; MH, 10,000 hours; MV, 24,000+ hours; and TH, 2,000 hours. The initial lumens and mean lumens for each type follow next: HPS, 140,000/126,000; MH, 110,000/88,000; MV, 63,000/48,500; and TH, 35,800/34,730. Colors vary, too. HPS is a soft orange hue, MH is bright white, MV is medium white, and TH is natural daylight white. Ask somebody who has used this kind of lighting which color is best for the work you plan to do.

The advantages perceived for these different types of light sources are interesting and they, too, may affect your choice. HPS lights have a high lumen output, but they also offer low lumen depreciation and glare, and low total system cost. MH lights have a high lumen output. One of their advantages is their good color rendition and overall lighting performance. MV lights offer long life and are particularly resistant to vibration. The lowest initial cost is for TH lights. They are instantly “on.” They require no ballasts. Their light is a natural, daylight-like color and they offer good aiming control for the user. Their initial lumens (35,800) depreciate very little. But there are also disadvantages perceived with each type. TH lights with their low initial cost offer a short lamp life and have a high surface temperature. MV lights have a relatively low lumen output and even that depreciates considerably. MH lights have a medium lamp life and a long restrike time. HPS lights have a higher initial cost and the soft orange color is not to everybody’s taste. Ask your supplier about the experiences of his customers with different types. Ask other contractors, too.

In Defense of Night Work
Some people told us they expected more projects to be bid for nighttime operations; others said they thought the practice was declining. Although we heard many reasons for not working at night, there are still reasons why the habit started. “In some cities, the problems caused by congestion and the backing up of daytime traffic, especially where interstates have busy ramps into the cities, are much more than those of annoyed drivers or even road rage,” comments Mark Andrew, manager at the Colorado State Highway Department. He is based in Colorado Springs, CO, one of the fastest growing cities in recent years. “We have seen virtual chaos when ramps have been closed without proper forethought or management of the diverted traffic. This affects the business of a city, not just the drivers. We have looked at the obvious disadvantages of night work for major cities and conclude that it is better than trying to accomplish the project in the daytime when traffic is at its peak.”

The size of the contracting company seems to be important in the bidding for night work, with bigger companies usually better financed to rent equipment and the necessary lighting. The size of the city seems important in the original decision. In the biggest cities, night work is not uncommon. “We do not have contracts for night work,” says James M. Beke, senior engineer for the City of Kentwood, MI. “The only ones I can remember are those that involved moving operations.” Kentwood is about 50,000, so it is not a rural town and there are many cities of that size in the US. For communities less populous than Kentwood, night work mandated by the municipality is rare. Let’s reiterate what has been obvious throughout our research. Most night work is funded by federal or state agencies. Or both. And it concerns road construction rather than the everyday contracting for commercial and residential projects that require graders, excavators and loaders.

Paul Hull writes on construction and environmental topics for several international magazines.

GEC - March/April 2005