Part-145: Fatigue

In addition to regulatory compliance, fatigue is mitigated by sleep:

  1. quantity of sleep;
  2. quality of sleep;
  3. restorative sleep.

Having said that, there are individual responsibilities as well as organization’s responsibilities.

The employee have to make proper use of sleep patterns given by the company.

This is the most controversial issue, but, if not mitigated, the fatigue starts at home.

AMC1 145.A.47(b) Production planning


(a) The way and the extent to which the organisation should consider the threat of fatigue in the planning of tasks and organising of shifts will vary from one organisation to another and from one maintenance event to another, depending on what maintenance is to be carried out, how, where, when and by whom.

(b) Fatigue is one example of human factors issues which should be taken into account by the management system, particularly for the planning activity. In this respect, where the
organisation activity is prone to fatigue issues, the organisation should:
(1) ensure that the safety policy required by point 145.A.200(a) gives due consideration to the aspects of fatigue;
(2) ensure that the internal safety reporting scheme required by point 145.A.202 enables the collection of fatigue issues;
(3) ensure that the threat of fatigue is adequately taken into account by the management system key processes (e.g. assessment, management, monitoring);
(4) provide safety promotion material and adapt safety training accordingly.
(c) The organising of shifts should consider good practices in the maintenance domain and
applicable rules. The resulting shift schedule should be shared with the maintenance staff sufficiently in advance so they can plan adequate rest.

The established shift durations should not be exceeded merely for management convenience
even when staff is willing to work extended hours.

(d) The organisation should have a procedure (including mitigations) to address cases where the working hours are to be significantly increased, or when the shift pattern is to be significantly modified, such as for urgent operational reasons. In cases not covered by that procedure, the organisation should perform a specific risk assessment and define additional mitigation actions,
as applicable. Basic mitigations may include:

(1) additional supervision and independent inspection;

(2) limitation of maintenance tasks to non-critical tasks;

(3) use of additional rest breaks.


(a) Fatigue may be induced by:
(i) the environment and conditions (e.g. noise, humidity, temperature, closed section,
working overhead) in which the work is carried out;
(ii) excessive hours of duty and shift working, particularly with multiple shift periods or patterns, additional overtime or night work;
(iii) travel to the maintenance location (e.g. jetlag, duration)
Fatigue is one of the factors that may contribute towards maintenance errors when it is not
properly considered as part of planning activities.

(b) Taking into account the threat of fatigue in the planning of maintenance tasks and organising
of shifts refers to setting up the maintenance and the shifts in a way that enables the maintenance staff to remain sufficiently free from fatigue so they can perform the planned
maintenance safely, including:
− providing rest periods of sufficient time to overcome the effects of the previous shift and to be rested by the start of the following shift;
−avoiding shift patterns that cause a serious disruption of an established sleep/work pattern, such as alternating day/night duties;
− planning recurrent extended rest periods and notifying staff sufficiently in advance.