The universal rule for backing up a passenger vehicle is simply not to. The difficulty comes when there is no other choice.
Technology and Semaphore
While crossover mirrors have been required on schoolbuses for roughly two decades, it is curious that no one has devised a mirror system to see behind the bus. Some buses have rear windows, and their view can be further enhanced (e.g., the need to see objects directly behind the bus near the ground level) by inexpensive technologies like the Rearscope – a periscope-like insert that displays objects below it. Of course, the space this technology occupies eliminates the ability for someone to use that same space to look directly behind the vehicle. Cameras with dash-mounted video monitors work reasonably well (unlike "flat," exterior side-view mirrors, they display only a limited area, and contain some distortion), but are costly.
An alternative is to delegate the viewing to a second party – an individual standing behind and slightly to the side of the vehicle who can be seen by the driver through one of the exterior, side-view mirrors. This approach unfortunately also has its limitations, since a very narrow range of information – like whether or not it is safe to back up at all – can be conveyed through hand signals, much less observed, through a mirror, often (i.e., with a full-size bus) more than 40 feet away. Further, there is no universal set of hand signals to convey much more information, and the likelihood that both the driver and signaler know "signing" (i.e., for communicating by and with someone hearing-impaired) is remote. This information could be augmented greatly if both the signaler and driver were to simultaneously communicate by cell-phone. Yet, oddly, I have yet to come upon this approach in any training documents.
If neither a fellow Earthling or technology is available, the driver may have the option of alighting, walking to the rear of the vehicle, and looking at what lies behind it. Unfortunately, this approach has limited applicability because, in the majority of cases, objects and activity behind the bus are likely to change during the driver’s walk back to the driver’s compartment. This is obviously the case when the vehicle must back down the roadway. But there are similar risks of objects entering the "backing zone" if it is in a parking lot, or almost anywhere else.
When one is forced to back up, judging distance is a challenging constraint, particularly when one’s only tool for doing so is a set of rear-view mirrors. Convex, side-view, exterior mirrors depict a closer view, yet at the cost of distorting it. Otherwise, the larger the vehicle, and particularly if it has a rear engine and no rear window, the more difficult this challenge becomes. Further, even a camera (unless there are multiple cameras – a genuine rarity) will not depict the entire area directly behind the vehicle.
One helpful approach is to employ as many tools as one can. Even without a "partner" helping to guide the vehicle in backing, using a combination of mirrors, back-up cameras, and "ground orientation points" can minimize the risks somewhat. As far as positioning the bus where you want its tail to end up, one may also set down traffic cones to mark its destination. When reflective, these cones are relatively easy to spot even at night (with minimal illumination from tail lights or other sources). If one adds pedestrian barriers and a "backing partner" with a communications device to the equation, these risks can be mitigated further still. But they can never be completely eliminated.
Environmental and Passenger Constraints
One problem more common to scheduled route buses and coaches is that they often stop at terminals built with loading docks which prohibit forward motion. In backing up in these situations, guidance from a "partner" is always helpful – but not perfect (for the reasons noted above). Many docks attempt to lessen the risks by prohibiting pedestrian movement around them. But this is still not a perfect solution, since it is not always possible to completely control pedestrian behavior in many situations, even with barriers, fencing and/or security personnel.
One approach, more common to motorcoach conversions, but increasingly starting to appear on commercial coaches, is the installation and use of docking lights – particularly valuable in tight or backing situations in a parking lot, hotel entrance or similar location, and especially so at night. If your duty cycle includes venues with such constraints, docking lights represent a sound investment.
Another problem deals with the type of bus or coach and what I term "crossing orientation:" Schoolbus passengers, for example, are supposed to cross in front of the bus, whereas transit and motorcoach passengers are supposed to cross behind it. But in roughly half the more than 60 crossing cases in which I have been involved, the crossing orientation was wrong for the type of vehicle involved. Would-be or former passengers behind the vehicle plus its backing up can create a deadly situation.
Because of the difficulties associated with backing up, drivers may choose to not enter certain areas if they are unsure about whether or not they can proceed forward – as for example, upon entering a parking lot. Of course, the driver could always alight, walk into the lot, and evaluate whether or not there are any forward-related impediments. But some drivers are lazy, some are stupid, and some do not care. So the fear of needing to back up haunts certain types of drivers more than others, and as a consequence, can discourage a vehicle’s appropriate forward movement.
Another constraint is the limited value of technologies like back-up alarms. While they should, in theory, warn a pedestrian to get out of the way, such a warning will not likely be heard by a motorist listening to a radio or CD player, much less with headphones on. It will certainly not be heard by a fixed object (other than the far-fetched scenario whereby the fixed object is a sensor designed to detect the signal, much less move the object to which it is attached out of the way, much less "return" the signal – and expect that return to be heard and interpreted by the original driver). Frankly, because some individuals are hearing-impaired, and particularly because children below age 13 (and even more so when below age 10) cannot reliably detect the direction from which a sound is coming, the risks of even a pedestrian recognizing (much less responding to) a back-up alarm are considerable.
Institutional and Operational Enigmas
The risks and challenges of backing up are so challenging that they have even bastardized an otherwise clear resolution of a much-needed class action lawsuit. In Melton v. DART, the disabled plaintiff lived in an apartment building to and from which he could only enter and exit from an alley behind the building. So when he requested a "reasonable modification" – that the complementary paratransit vehicle pick him up and drop him off in this alley — the transit agency refused, citing the risks associated with having to either back in or out, since the lot afforded insufficient room in which even the small minibus conversion could turn around. This issue is still unresolved years later, even though many examples of "reasonable modifications" would pose few problems, and because the issue has been resolved differently in different circuits (our court system is divided into 10 "circuit courts"). Those circuits which have not granted "reasonable modifications" have left some of our most needy and vulnerable public transportation passengers effectively stranded – with the risks of backing up only one among many poor or limited options. But because backing up is among the scenarios, its risks have effectively poisoned the environment in which other reasonable modifications that would likely involve little or no risk might otherwise be granted.
Compounding these problems, because backing up is often prohibited, and almost always frowned upon, it is almost never practiced. So when it must be executed, its performance becomes far more risky because it is also almost always improvised.
Vacuums and Vacancies
Having trained tens of thousands of drivers through certain venues (mostly through magazine articles and presentations) and small groups face-to-face (like those in the 70-vehicle paratransit system I owned and whose operations I directed), I have occasionally come across a few "tricks." But particularly as most of them were applicable only to limited situations, I have kept track of very few. For the most part, drivers are taught simply not to back up unless either assisted in doing so, if the vehicle contains the technology to see behind the bus, and almost always only when instructed to do so by a dispatcher (who may have more knowledge and better judgment than the driver, but obviously no remote view of objects or activity behind the bus).
There are limited choices for backing up large vehicles, and even fewer choices for those with rear engines (and thus no rear windows). This problem is compounded by the fact that whatever means of doing so may exist, they are almost always appropriate only within certain scenarios, and/or under certain circumstances. Filling in the matrix, so to speak, would create an awkward body of knowledge that would difficult to use, much less master. Further, devoting training time to such a complex undertaking so rarely needed would likely displace the coverage of more important and useful topics within the overall training agenda.
I would very much like to see a body of knowledge on this unique subject created. However, if one emerged, I am not certain its contents could be boiled down to a manageable and memorable amount of information. While I cringe when reviewing an article that ends with a plea for further study – often a cop-out or disclaimer – this topic is likely one that warrants it.