Integration of Safety Right from the Design of a Machine

The CNESST’s “machine safety” action plan launched in 2005 has certainly raised awareness and improved the safety of a lot of equipment in Quebec, although there is still some way to go. It is the owner’s responsibility to ensure that their equipment is safe. This is the law (LSST, 2020).

They therefore have the choice between modifying their own equipment, acquiring new equipment, which is generally safer, or acquiring second-hand equipment which may then have to be modified as well.

Securing existing equipment has its share of difficulties. First, there are significant costs between engineering, manufacturing, and installation. Then modifying existing equipment means having to deal with elements that cannot be modified. Older technologies sometimes do not allow for the integration of more modern and effective corrective measures. But also, and more generally, it is rarely a given for integrators to use the most effective method recommended by the standards, namely intrinsic prevention (elimination or reduction of risk by design) (ISO 12100, 2010; CSA Z432, 2016).

Moreover, surveys regularly reveal a design flaw as one of the causes of the accidents analyzed (Chinniah et al., 2019). However, according to section 63 of the LSST, “no one way manufacture, supply, sell, rent, distribute, or install a product, process, equipment, material, contaminant or hazardous material unless they are safe and comply with the standards prescribed by regulation.” Manufacturers are therefore also more or less directly accountable for the safety of their equipment.

Although the standards are more and more comprehensive and knowledge of the prevention approach has evolved a lot, putting it into practice is not always easy, even for manufacturers. They are often penalized with costs and delays (De La Garza, 2005; Ghemraoui et al., 2009). At least, this is the case when safety is addressed separately from the functional aspect, or even only at the end of the project and therefore with a corrective approach. The manufacturer then finds itself in almost the same situation as an integrator who has to upgrade existing equipment.

A study published in 2019 looked at the practices and needs of manufacturers in Quebec (Chinniah et al., 2019). The manufacturers participating in the study were very familiar with prescriptive approaches to assessing and reducing risk. However pressure from customers who demand the strict minimum of safety and competitive prices often leads manufacturers to favor simple and more economical measure such as guards. However, some have succeeded in demonstrating that the integration of protective devices such as light curtains, for example, becomes an advantage by facilitating the use of their equipment. Easier and more user-friendly equipment will promote productivity on a daily basis. Indeed, a harmonious integration of safety from the design has a potential positive effect, in particular on staff retention, the duration of interventions or the needs of interventions. The study also showed that bypassing means of protection is a widespread concern among manufacturers. However, in addition to the methods and technical means described in the standards, the adequacy of risk reduction measures with user needs has a major positive impact on this phenomenon.

Manufacturers have, as explained above, more leeway for this. However, this principle also applies to anyone wanting to secure existing equipment. It is advisable to take the time to properly design the risk reduction measures according to the needs of the users (operator, mechanic, etc.) to ensure effective, durable, and well-received protection.

References:

Chinniah, Y., Gauthier, F., Abdul-Nour, G., Jocelyn, S., Aucourt, B., Bordeleau, G. (2019). Étude exploratoire sur les pratiques des fabricants de machines au Québec en lien avec l’intégration de la sécurité des machines dès leur conception. IRSST, Rapports scientifiques, R-1082

CSA Z432 (2016). Protection des machines

De La Garza, C. (2005). L’intégration de la sécurité lors de la conception de machines à risques pour les opérateurs : comparaison de logiques différentes de conception. PISTES, vol 7, n°1, 17

Ghemraoui, R., Mahieu, L., Tricot, N. (2009). Design method for systematic safety integration», CIRP Annals – Manufacturing Technology – vol 58, pp 161-164

ISO 12100 (2010). Sécurité des machines — Principes généraux de conception — Appréciation du risque et réduction du risque

Loi sur la santé et la sécurité du travail (2020)

Règlement sur la santé et la sécurité du travail (2020)