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The Use of Portable Scales – Part One

Want to get some emotions heated up in a room full of truckers and police officers? Bring up the topic of portable scales. The carrier industry will bemoan their accuracy and accuse police officers of using them solely for revenue generation. Police officers will stand on their accuracy and argue their use saves time by not dragging truckers miles and miles to a fixed scale. While these disputes may never be settled, there are some objective truths about portable scales which can be clarified for all parties.

For the sake of argument, portable scales are a tool. Like any instrument, they can be used both properly and improperly. There is no scale, fixed or portable, which measures truck weights to the micro-fraction of a pound perfectly. So to say portable scales are “accurate” or “inaccurate” is a waste of breath.

What irritates the carrier industry most about portable scales are perceived misuses in their application by police officers. The erroneous thinking is that so-called “common sense” practices are codified by law or regulation. The truth is the law has very little to say about portable scales.

The Illinois Vehicle Code explicitly allows the use of portable scales. This is found in 625 ILCS 5/15-112(a). There is also some language about who can use portable scales, the training required and the regulatory authority governing the certification of portable scales. That’s it.

What is lacking is any statutory guidance about how to use portable scales. The Illinois Department of Agriculture is the regulatory agency which oversees the certification of all scales, but their policies and administrative rules do not provide guidance to law enforcement practices.

Here is a list of misconceptions about how portable scales are to be deployed by law enforcement:

Level Ground

Of course, police officers should only weigh trucks on level ground. It should be noted there is no perfect level ground. Every street and parking lot is pitched somehow. The argument is a moot point because there is not law or regulation which says the ground must be level.

What is level? Side to side? Front to back? All axles level? There is no definition as to what level ground legally means.

Inclement Weather

Wet pavement is slippery and can be a hazard to police officers using portable scales. Most truck officers probably won’t use them in the rain anyways. The law, however, does not say portable scales cannot be used them in the rain. Nor does the law say they cannot be used in the snow, bitter cold or excessive heat.

Axle by Axle Weighing

It is true full draft weighing (gross weight with all axles on the scale) of trucks is mandated for commerce under federal law in the NIST 44 Handbook. However, highway law enforcement is exempt from the handbook. This is listed not only in the handbook itself, but also in the Illinois Vehicle Code.

What this means is law enforcement can weigh axle by axle on both fixed and portable scales. So whether or not a truck has five axles or nineteen axles, the law never says all axles must be weighed simultaneously on portable scales.

Adjustable Axles

Many trucks have axles which raise and lower under pneumatic or hydraulic pressure. In most instances, adjustable axles correct themselves to compensate for uneven pavement to keep the load and vehicle balanced. The law never says vehicles with adjustable axles cannot be weighed on portable scales.

Liquid Loads

Yes, liquid loads like fuel, water and milk can register different readings when weighed axle by axle if the load is sloshing around. Again, like the adjustable axle argument, the law does not prohibit portable scales from being used to weigh liquid loads.

The ITEA goes to great lengths to make sure police officers they train use portable scales in a fair and reasonable way. Next week, this article will go through each of the above scenarios and explain the common sense methods police officers should use when operating portable scales.

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