Table 1.

The structure of the SMS-MAH according to Annex B and the sources of resilience.

SMS POINT		RESILIENCE SOURCE	STATUS	Resilience Cornerstones
Policy		See for details § 4.1.4		ANTICIPATE
1.Resources and Leadership		Resilience is a non technical skill, which can be taught and learnt. It is essential to include in safety training program, mandatory in SMS-MAH, resilience classes for plant managers and safety managers. (Agnello et al., 2017)	Sometimes present;to improve	ANTICIPATE
2.Risk Assessment		The bow-tie method has been adopted for a decades to have an immediate understanding of preventive and protective barriers. The redundancy of barriers is essential also to allow safe operations also in the event of the failure of a barrier due to unexpected changes in external context. (Agnello et al., 2012)	Already Present	REACT
3.Operating Control	Service	Procedures for the safe shutdown and start-up in the event of unexpected and prolonged suspensions of the service. For instance, many hazardous materials degrade over time. Their quantities in storage must be kept to a minimum and their situation must be monitored. Nitrogen inerting must be maintained to protect against explosive atmospheres. It is important that the plant is inspected and tested before rebooting and that the boot process is duly monitored. The formation of hazardous vapours should be considered in chemical warehous, in the event of prolonged service interruption.	Sometimes present;to improve	MONITORING
	Maintenance	A safety walk consists of an “advanced” inspection of one or more equipment, logical units or the whole establishment. For each equipment item, through the data provided by a netwok of sensors, the inspector determines information about ageing, in the form of probability of failure, as well as the expected residual lifetime. (Milazzo et al., 2019)	Sometimes present,to improve	MONITORING
4.Management of Change		The definition of safe limits for process conditions, variables and activities and training of the staff to recognise significant changes. Combined with knowledge of established operating procedures, this additional training will allow the staff to activate the Management of Changes system when appropriate (Han Siog et al., 2017)	Sometimes present,to improve	MONITORING
5.Emergency Management		Emergency Training is usually based on the simualtion of accidental scenarios as described in the risk analysis. It is essential to include in the training programs unexpected scenarios or, better, unexpected disturbance to expected scenarios to verify the robusteness of the system	Sometimes present,to improve	ANTICIPATE
6.Performance Evaluation		The duly registration and discussion of minor accidents and near misses has been for years a pillar of the SMS. Learning from experience is essential to improve the SMS and adapt it to changes in the context. Including anomalies in the near-misses management allow increasing the attention to the weak signals, anticipating potential weaknesses, which could jeopardise the SMS (Bragatto et al., 2015)	Already Present	LEARNING
7.Review and Improvement		In general, a revision of the SMS-MAH should include the concept of resilience, promoting awareness of the risks deriving from the external context, which are not always a priori foreseeable, but to which an organisation must be able to react ensuring the continuity of the activities and a rapid recovery in the event of forced service interruption, adaptation to new models, in the event of changes in the external context are permanent. (Podgórski, 2015)	Sometimes present,to improve	REACT