Too often to the untrained eye an engineering drawing seems as if it is just lines on a large piece of paper. The untrained eye viewing the document cannot fathom even for one moment what these lines mean and very often come away with one simple statement especially during a dispute, that all the engineer gave me was just lines on a large piece of paper.
The response of engineers to this comment and comments like these have been to ignore them altogether without wondering, hmm could I have left another impression that would not have resulted in this comment being made in the first place. Normally, we get upset at the comment and leave the matter just as it is, but we shouldn’t as not addressing this matter and matters like these leave the consumers with the wrong impression of the work of an engineer.
The engineering profession is a regulated body just like how lawyers and doctors are regulated to practice. However, the level of regulations varies from jurisdictions to jurisdictions. In the United States where I also practice, the profession is tightly regulated and one cannot style or call himself an engineer without the appropriate license, no matter the level of engineering training he or she has undertaken. In Jamaica the profession is also regulated but not as tightly. Yes, the laws governing the practice of engineering are in place, but for the most part they are ignored by both the public and private sectors.
The simple truth is that the lines on the paper are lines but they represent hours of engineering calculations to arrive at these lines. From the electrical engineer who before drawing one line has to calculate the power requirements of the load, the voltage drop, the control scheme, down to the quantum of wires that can be drawn into each conduit, to the mechanical engineer who has to calculate the heat load to determine the capacity of the cooling system, the pipe sizes that will ensure that water flows in all the pipes of four bedroom/bathroom house when all four bathrooms are in use simultaneously. The fact that you can turn on your light without feeling a tingly electrical shock, or to turn the tap on and water flow at the required pressure is not by accident. The fact that the road one drives on daily, the bridges crossed can withstand the weight of vehicular traffic without failure is a testament to the calculations that went into the design.
In addition to the calculations the engineers also undertake another function that is critical to any design, which is value engineering. An oversized air conditioning system in addition to costing more will not work as effectively as a unit properly sized at a much lower cost. This is the value for money that engineers provide during every design undertaken.
Therefore, the next time you see lines on an engineering drawing, it is not just lines, since it represents all the calculations that the design requires.