1. Overall presentation of the application guide on CSM Design Targets (CSM-DT)
Workshop on CSM-DT, November 2016
Dragan JOVICIC, EU Agency for Railways

2. Application Guide on Regulation 2015/1136 – 6 parts PART I - Explanations of the Legal Text
1.1. What are the CSM-DT?
1.2. Is use of CSM-DT mandatory? (¨Proposer’s responsibility)
1.3. When to use the CSM-DT?
1.4. What technical systems do CSM-DT apply to? 1
Scope of use of CSM-DT
How do CSM-DT fit within overall CSM RA process? 2
Systematic failures and safe integration into the railway system
3.1. Overall requirements in § of Reg. 2015/1136
3.2. Additional guidance retrieved from CENELEC 3
4.1. Introduction (link to chapter 1)
4.2. Explanation of terminology in §2.5.5
4.3. Explanation of the definition of a “technical system”
4.4. Process proposed for selecting appropriate CSM-DT class
4.5. Precautions for the selecting appropriate CSM-DT class 4
Choice of appropriate severity class/category
5.1. Level of function to which the CSM-DT is applied
5.2. Use of barriers
5.3. Conditions for the use of barriers (intentional safety measures)
5.4. Barriers not permanently present
5.5. Level of application of CSM-DT
Application of CSM-DT and use of external barriers 5

3. Application Guide on Regulation 2015/1136 – 6 parts PARTS II to VI – Informative Annexes
Informative only and cannot be applied without analysis specific circumstances and needs of TS under assessment
 Does TS have similar use and application conditions to those stated in Annex 1?
ANNEX 1
List of informative examples of technical functions and applicable CSM-DT class II
ANNEX 2
Cannot be applied as such
Short examples of the functional level at which CSM DT can be applied and use of external barriers
III
ANNEX 3
Agency example on use of CSM-DT (hot box detector)
Overall example illustrating how CSM-DT fit within the overall risk assessment process of the CSM and how to carry out a quantitative risk with the use of external barriers IV
Overall example illustrating how CSM-DT fit within the overall risk assessment process of the CSM for the standardised protection of level crossings on secondary lines with low or medium traffic conditions (Infrastructure) V
ANNEX 4
Swiss NSA example
A5.1 Example 1 : Emergency brake control of a locomotive
A5.2 Example 2 : Train door opening authorisation
A5.3 Example 3 : Control of the traction cut-off
A5.4 Example 4 : Transmit traction and brake command
A5.5 Example 5 : Level crossing case study
ANNEX 5
Examples from the sector VI

4. Application Guide on Regulation 2015/1136 Scope of use of CSM-DT
What are CSM-DT?
harmonised quantitative safety requirement
“can be used” for random hardware failures of E/E/PE technical systems
when used risks arising from failures of functions of TS is acceptable under conditions of point of Reg. 2015/1136
do not represent a national safety level such as CSTs nor NRVs
is not general risk acceptance criterion for whole railway system of a MS (such as GAME or ALARP)
established mainly to support mutual recognition of technical systems

5. Application Guide on Regulation 2015/1136 Scope of use of CSM-DT
Is use of CSM-DT mandatory?
not mandatory as Reg. 402/2013 does not impose any order of priority
proposer free and responsible for choice among CoP, comparison to similar Ref. Syst. or explicit risk estimation, or a combination, which makes risk acceptable
Reg. 2015/1136 stresses that CSM-DT “… shall …” neither be used “… for the design of purely mechanical technical systems” nor for controlling “the hazards arising from the purely mechanical part …” of a mixed TS
 CSM-DT cannot be used for mechanical systems but although application of (qualitative, quantitative or both) explicit risk estimation remains an option for the associated risk control, it is preferable to use either CoP or Ref. Syst.
pneumatic TS are not mentioned  use of CSM-DT not forbidden provided proposer demonstrates the risk acceptability and the CSM assessment body accepts the demonstration

6. Application Guide on Regulation 2015/1136 Scope of use of CSM-DT
When to use the CSM-DT?
when carrying out a significant change
for technical systems [not to operational and organisational changes]
when proposer performs quantitative risk assessment in explicit risk estimation
Conversely, when proposer demonstrates that risk is acceptable with the use of qualitative risk control measures, proposer cannot be obliged to perform additional quantitative risk assessments
to set up quantitative safety requirements for the design of a technical system
to support mutual recognition of results of risk assessments of TS, or for other purposes at the discretion of proposer, if he can demonstrate risk acceptability
represent “ the most demanding design targets that can be required for mutual recognition ”. When used, mutual recognition is automatically ensured.
more demanding design targets may be requested, through a notified national rule, only if it is necessary to maintain existing level of safety in the MS

7. Application Guide on Regulation 2015/1136 Scope of use of CSM-DT
Flowchart for the applicability test

8. Application Guide on Regulation 2015/1136 Scope of use of CSM-DT - Flowchart for the applicability test

9. Application Guide on Regulation 2015/1136 Scope of use of CSM-DT - Flowchart for the applicability test

10. Application Guide on Regulation 2015/1136 Scope of use of CSM-DT
What technical systems do CSM-DT apply to?
for Electrical, Electronic and Programmable Electronic (E/E/PE)( ) technical systems, without prejudice to proposer’s responsibility to choose RAP
shall not be used for design of purely mechanical technical systems (e.g. wheel axles) or for the design of the mechanical part of a mixed technical system
Reg. 2015/1136 does not recommend any specific approach for that HOWEVER although (qualitative, quantitative or both) explicit risk estimation remains an option, it is preferable to use either CoP or Ref. Syst. for the control of hazards arising from a purely mechanical TS
for E/E/PE technical systems approved methods exist in recognised standards (e.g. CENELEC 5012x series of standards or EN 61508) to demonstrate the achievement of quantified design targets and to cope with systematic failures which cannot be quantified

11. Application Guide on Regulation 2015/1136 How do te CSM-DT fit within the overall risk assessment process of CSM?

12. Application Guide on Regulation 2015/1136 How do te CSM-DT fit within overall risk assessment process of CSM?

13. Application Guide on Regulation 2015/1136 How do te CSM-DT fit within overall risk assessment process of CSM?

14. Application Guide on Regulation 2015/1136 How do te CSM-DT fit within overall risk assessment process of CSM?

15. Application Guide on Regulation 2015/1136 Systematic failures and Safe Integration within the railway system

16. Application Guide on Regulation 2015/1136 Random hardware failures and Systematic failures

17. Application Guide on Regulation 2015/1136 Choice of the appropriate severity class of CSM-DT

18. Application Guide on Regulation 2015/1136 Choice of the appropriate severity class of CSM-DT

19. Application Guide on Regulation 2015/1136 Choice of the appropriate severity class of CSM-DT

20. Application Guide on Regulation 2015/1136 Only possible cases of CSM-DT vs. number of (affected persons; victims).

21. Application Guide on Regulation 2015/1136 Application of CSM-DT in presence of intentional external barriers
CSM-DT apply to failures of fcts of TS only if can lead directly to accident  CSM-DT limited to a few rather high level functions of railway system
In practice, a technical function can be delivered by a combination of TS  to avoid misapplication of CSM and CSM-DT for risk assessment, the way the technical function is actually delivered needs to be considered
Usually, additional safety measures outside the TS are also put in place  consequence is not direct and CSM-DT do not apply straight forward to TS
Then CSM-DT is to be applied at the level of the overall architecture of the considered function taking into account the way the function is achieved by the TS and the efficiency of the external safety measures/barriers
If an external barrier is implemented, less demanding design targets may be used for TS if those external barriers does not reduce the overall safety level
Such cases are illustrated in chapter 5 of the application guide on CSM-DT

22. Application Guide on Regulation 2015/1136 Application of CSM-DT in presence of intentional external barriers
Use of barriers may impact mutual recognition, as Article 15(5) of CSM requires a demonstration that system is "used under the same functional, operational and environmental conditions as the already accepted system and that equivalent risk acceptance criteria have been applied“
 equivalence of safety barriers used in one Member State needs to be demonstrated with those used in another Member State.
External barriers need to be identified as an "application condition" for the technical system and included in the Hazard Record, including the actor responsible for controlling the external barriers
Barriers should be intentionally implemented either to reduce the frequency of occurrence of a hazard or to mitigate the severity of the potential consequence of the hazard. This does not mean that the barrier is only implemented for this purpose; the barrier(s) may also serve other functional purposes of the railway system as well.

23. Application Guide on Regulation 2015/1136 Application of CSM-DT in presence of intentional external barriers
The barrier needs also to be monitored by the organisation responsible for the operation of the TS
Consideration of barriers is allowed even though the barrier may be used outside its originally intended purpose. However, demonstration of the barrier effectiveness is necessary
Generally external barriers should only be considered if they are permanently present
If barriers are only present under certain constraints (e.g. operating conditions or specific circumstances that cannot be controlled) then their use needs to be considered with precautions
The risk assessment should take into consideration both the effect of the presence and of the absence of the barriers in the railway system. The railway system needs to be able to achieve the required safety level also when the barrier is not present in the system

24. Application Guide on Regulation 2015/1136 Informative examples contained in the Annexes
The examples contained in the Annexes of the application guide on CSM-DT are illustrated in separate presentations