Luca Belgero, Alessandro Mazzeranghi
In the field of tissue, occupational safety principally passes through machine safety. That is why we treat the theme in a specific manner and guaranteeing the safety of the machines that operators work with is a main objective of any company, independently of applicable national laws. It is a question of ethics, but also of common sense: accidents on the job damage the heritage of corporate competences, dishearten people, cause crises for the company.
So even under the strictly utilitarian profile, they are events to be avoided.Having said that, we have to deal with reality, too.
Safety techniques are evolving thanks more to the companies producing safety systems or machines than to norms that sometimes express a state of the art that seems fruit of the imagination rather than concrete knowledge of the industrial field in reference.
Given that, hence speaking concretely, thinking about following the evolution of the state of the art by continuously updating the machines year after year, innovation after innovation is something clearly unreasonable and not even the most attentive legislations demand as much. Let us see why.
UPDATING OLD MACHINES TO THE STATE OF THE ART: IS IT REALLY THE RIGHT CHOICE?
Let us consider having a roll converting machine manufactured at the end of the 1980s that is still perfectly running since, in the course of time, it has undergone attentive maintenance that has never, however, entailed revamping or upgrading interventions.
If we look at a roll converting machine by the same manufacturer placed on the market today, we find a completely different product both as far as features and safety are concerned.
To take the new machine as the state-of-the-art refe-rence for adapting the safety aspects of a machine that is over twenty years older would be irrational for two reasons:
First of all, the safety aspect of today’s machines is based on completely different electronics from those that characterized machines in the ‘80s, and under the man/machine interaction profile, too, solutions exist today that allow minimizing it and that are impossible to replicate on old machines without revolutionizing them both mechanically and electrically.
Secondly, because such an investment on an old machine - albeit it well preserved - is senseless under the corporate management profile.
So state of the art is not the reference for the safety of older machines. Rather, the reference should be the outcome of a concrete risk assessment that will highlight the safety problems present and allow defining technical and organizational measures to reduce risks to an acceptable level.
We could hence speak of a minimum safety level to pursue that would not be ethically correct and/orcorporately reasonable to disregard. A level that we must be able to attain without interventions that entail “redesigning” the machine.
SUBSTANTIAL MACHINE MODIFICATIONS AND SAFETY.
Let us start off by repeating that we do not want to speak about national laws here, but rather about proper corporate management that exploits situations that may arise in order to reap the best benefits under every possible profile.
So let us consider what concretely happens whenwe decide to make an important modification to an existing machine, a modification that goes well beyond ordinary or extraordinary maintenance.
When we decide on the modification, clearly the intention is to gain a competitive edge. What we want to dois to adapt an existing machine to new demands instead of buying a new one.
To obtain a really important result, we must intervene on the machine at an in-depth “design” phase and with a level of invasiveness such as to hypothesize a refurbishing of some mechanical parts and of many elements of the control system.
So by undertaking such deep-seeded modifications, putting the very conception of the machine into question, we clearly acquire all the elements and consider all related aspects, even a strong and radical improvement of the safety level. At this point, it really does make sense to reconsider the level of safety, taking state of the art as reference.
And to boot, possible improvements will also entail reduced costs because they will in any case exploit many elements already necessary to put the substantial modification we want into practice.
HOW TO UPDATE THE SAFETY OF MACHINES THAT HAVE UNDERGONE SUBSTANTIAL MODIFICATIONS.
Just one aspect remains to be handled carefully in order to avoid surprises or useless complications: understanding what is important to do and what is instead useless or even counter-productive, in terms of updating safety when dealing with substantial modification interventions of a machine.
Evidently, a machine that has been substantially modified in productivity and/or the types of productions that can be made on it is not a completely new machine. So the interventions, including those to improve safety, must come to terms with a series of “physical” restrictions that are not present for those who start designing a new machine “from scratch”. An attentive and precise logical strategy is necessary that allows distinguishing what is indispensable from what is only useful and from what does not lead to any concrete benefit at all. To do this, speaking of safety, we must proceed through an attentive and precise risk assessment and a subsequent analysis of the technical but also organizational measures that can be adopted in order to reduce residual risk to a minimum. So it is true that solutions regarding the safety of new machines present on the market are an essential reference and comparison point, but it is just as clear that in speaking about existing machines, we will per force have to filter reasoning through the foundational instrument of risk assessment.