SAFETY, RISK, ACCIDENTS AND STANDARDS IN REFRIGERATION

Transcription

1 SAFETY, RISK, ACCIDENTS AND STANDARDS IN REFRIGERATION IIR Working Group on Refrigeration Safety Valencia, June 19 th, 2018 Holger Koenig ref-tech engineering Engineering for refrigeration technologies Lindau am Bodensee, Germany Contact:

2 IIR Working Group on Refrigeration Safety Agenda The definition on Safety and Risk and meaning for refrigeration Risk in real life, examples Conclusion and expectation for this IIR , 2

3 The definition on Safety and Risk and meaning for refrigeration Safety: is the condition of being protected against harmful conditions or events, or the control of hazards to reduce risk. Risk: combination of the probability of occurrence of harm and the severity of that harm. Risk Assessment: quantitative evaluation of risk (ISO 12100: Safety of machinery General principles for design Risk assessment and risk reduction) , 3

4 The definition on Safety and Risk and meaning for refrigeration Applied to safety classification of refrigerants Protected? Harmful conditions? Control of hazards? higher risk GWP increase higher risk Flammability Toxicity Higher flammability A3 B3 Flammable A2 B2 Lower flammability A2L B2L Non flammable A1 B1 Not safe? Safe? , 4

5 The definition on Safety and Risk and meaning for refrigeration Risk Evaluation Process for refrigeration systems Consideration of ISO Guide 51 - Development of an Operational Mode Risk Assessment (HAZOP) - Identification of the tolerable risk level - Risk reduction by design protective measures organisation of safe working conditions and processes , 5

6 ISO Guide 51 Design (ISO ,2,3) Operation (ISO ,4) Key protective measures to be addressed for the use of flammable refrigerants , 6

7 Risk Evaluation Process ref-tech , 7

8 Risk in refrigeration industry Several risk Assessments show that refrigeration systems are generally very safe and show low numbers for frequency of hazards and severity , 8

9 Risk assessment standard: real life leak rates and frequencies (ISO DIS 20854) Normal operation Normative design requirements Not-normal operation Accidental type situation Design requirements depending on results from OMRA, safety concept and refrigerant type Normal and foreseeable misuse Mandatory for evaluation in OMRA & Design Process , 9

10 Risk Evaluation Process A risk assessment shall, including but not limited to - Consider basic fluid properties - Events in lifetime operation of the product and - Include results from reality testing Examples - Explosion pressure of R32 vs. R290 (Zang et.al.) - LFL of HFC s as function of humidity / temperature (JRAIA) - The 150g = safe assumption (BAM) - Counterfeit refrigerants R134a R40 (reefer container) - Improper R290 plant (Dissen) - Misleading Standards , 10

11 Improper Service: explosion of a R290 plant in a try container The incident is currently under investigation but the police blamed improper procedures during the maintenance work. It has been widely reported that the system was using highly flammable propane refrigerant but the Cooling Post has not yet been able to confirm this. In addition, an earlier confusing statement by the police on the maintenance work being carried out said that the propane gas had to be drained, cooled down with nitrogen and cleaned , 11

12 Counterfeit refrigerants in shipping industry (Lawton 2013, IIR Note 23, 2012) During 2011 the compressors of a number of reefers inexplicably exploded with the loss of life, the cause of the explosions was counterfeit refrigerant Cost-driven risks: R40 (CH 3 Cl) as cheap R134a successor A global problem , 12

13 Explosion pressure of R32 vs. R290 (Zang et.al.) , 14

14 Flammability of refrigerants (JRAIA) Effect of humidity on flammability limits Event with low probability , 15

15 Risk Evaluation, reduction including commercial driving forces Identify leak rates and frequencies in real operation Clarify terms: normal operation, indented use, foreseeable misuse, accidental events Evaluate the tolerable risk and risk reduction Clarify: responsible operator, process or product owner Monitoring of events and implement mitigation procedure Implementation of continuous improvements processes - Implementation of training and verified certification programs - Development of commercial incentives for technicians and stakeholders , 16

16 Conclusion and expectation for this IIR safety classification of refrigerants Protected? Harmful conditions? Control of hazards? This safety classification is a misleading design criteria in refrigeration and has limited meaning with regard to safety! The correct safety and design evaluation for a refrigeration system shall be made by mitigation of the risk in operation! , 17

17 Conclusion and expectation for this IIR Development of a IIR Guideline / IIR Note for - Scientifically verified definitions of key terms, clarification of wording and understanding for Safety, Risk, Hazards, etc. applied to refrigeration for risk evaluations processes for refrigeration systems using flammable refrigerants Review of foundations for safe work environments applied for technical work and description of methods for risk mitigation - For business enterprises, operators, owners, management, politicians , 18

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