Risk assessment of ammonia leakage by fault tree analysis: Case study in the ice manufacture, Chonburi province

Teeranun Nakyai; Sujee Phatrabuddha; Patomphong Homsri; Nantaporn Phatrabuddha

doi:10.12688/f1000research.159905.1

Home Browse Risk assessment of ammonia leakage by fault tree analysis: Case study...

ALL Metrics

-

Views

-

Downloads

Get PDF

Get XML

Export

▬

✚

Research Article

Risk assessment of ammonia leakage by fault tree analysis: Case study in the ice manufacture, Chonburi province

[version 1; peer review: 1 approved with reservations]

Teeranun Nakyai¹, Sujee Phatrabuddha², Patomphong Homsri¹, Nantaporn Phatrabuddha¹

PUBLISHED 12 Feb 2025

Author details Author details

¹ Industrial Hygiene and Safety, Burapha University, Mueang Chonburi District, Chon Buri, Thailand
² Process and Industrial Engineering, Mahanakorn University of Technology, Bangkok, Bangkok, Thailand

Teeranun Nakyai
Roles: Conceptualization, Methodology, Writing – Original Draft Preparation

Sujee Phatrabuddha
Roles: Conceptualization, Investigation, Methodology

Patomphong Homsri
Roles: Conceptualization, Investigation, Methodology, Resources

Nantaporn Phatrabuddha
Roles: Conceptualization, Methodology, Writing – Review & Editing

OPEN PEER REVIEW

REVIEWER STATUS

Abstract

Introduction

Ammonia leaks during ice production can have significant impacts on the health of workers, nearby communities, and the environment. Exposure to ammonia can lead to both acute and chronic adverse effects.

Methods

A basic cause analysis of ammonia leakage in an ice production facility in Chonburi Province was conducted using Fault Tree Analysis (FTA). Boolean algebra equations were applied to construct primary causes, define failure type, and establish prioritization. Risk assessment was performed based on the criteria established by the Department of Industrial Work, incorporating both likelihood and severity to determine the risk level.

Results

The results identified 22 potential scenarios that contributed to ammonia leakage. When prioritizing these scenarios, dust accumulation and clogging of the fan, uninsulated ammonia transport pipes, coil obstruction due to scale build-up, incorrect shaft bearing motor, and the use of non-heat-resistant lubricants were significant contributors. Risk assessment analysis indicated both moderate and high risk of ammonia leakage. The use of incorrect bearing and non-heat-resistant lubricant in pumps was identified as high-risk, with a score of 9.

Conclusions

To mitigate this risk, it is necessary to replace bearings with standard ones and use heat-resistant lubricants to prevent pump failure and reduce cooling inefficiencies, which could lead to ammonia leaks. Regular inspection and maintenance should also be implemented. Furthermore, it is essential to enhance workers’ skills and expertise through training and practice.

Keywords

risk assessment, ammonia, fault tree analysis, ice manufacturing

Corresponding author: Nantaporn Phatrabuddha

Competing interests: No competing interests were disclosed.

Grant information: This research project was supported by a grant (ID 02/2566) from the Public Health, Burapha University, Thailand .
The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Copyright: © 2025 Nakyai T et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

How to cite: Nakyai T, Phatrabuddha S, Homsri P and Phatrabuddha N. Risk assessment of ammonia leakage by fault tree analysis: Case study in the ice manufacture, Chonburi province [version 1; peer review: 1 approved with reservations]. F1000Research 2025, 14:192 (https://doi.org/10.12688/f1000research.159905.1) First published: 12 Feb 2025, 14:192 (https://doi.org/10.12688/f1000research.159905.1) Latest published: 12 Feb 2025, 14:192 (https://doi.org/10.12688/f1000research.159905.1)

1. Introduction

An analysis of chemical spill accidents in Thailand over the past five years (2017-2021) revealed a total of 237 incidents. These accidents resulted in 414 injuries and 25 deaths, with fire-related accidents being the most frequent, accounting for 49.37 % of all incidents.¹ In terms of chemical leaks, Chonburi was identified as the province with the second highest number of chemical accidents nationwide. The industry with the highest frequency of chemical accidents were ice manufacturing, frozen food production, and cold storage, respectively.^2–4 These factories use ammonia at various stages of their cooling processes.

Ice production plants, in particular, use ammonia as a refrigerant because of its high efficiency and low cost compared to chlorofluorocarbon (CFC) refrigerants and its non-destructive impact on the ozone layer.⁵ However, ammonia is classified as a hazardous substance and poses significant health and safety risks.⁶ It is stored under pressure and is classified as Class 2.3, indicating both poisonous and corrosive.⁷ Additionally, under Thailand’s Hazardous Substance Act 1992, ammonia is classified as a Type 3 hazardous substance. The primary health and safety risks of ammonia are outlined by its risk phrases: R10 (flammable), R23 (toxic if inhaled), R34 (causing burns), and R50 (highly toxic to aquatic life).⁸

The most common causes of ammonia leaks include the use of equipment, such as damaged components (e.g., leaks in pipelines, joints, and valves), inadequate safety procedures, and lack of proper and continuous maintenance.⁴ Ammonia can react with water and humidity inside a factory to produce ammonium hydroxide, which is highly corrosive to gas pipelines and valves, leading to ammonia leaks.⁹ Additionally, improper storage of ammonia containers, such as failing to designate a specific chemical storage area without neglecting to post warning signs, can also contribute to leakage. Many ice factories are old and are often located in densely populated areas. Ammonia leakage, which is acutely toxic, poses a significant health risk to both employees and the surrounding community.¹⁰ Ammonia exposure can cause eye irritation, conjunctivitis, tearing, eyelid twitching, and skin burns.¹¹ The inhalation of ammonia can result in headaches, excessive salivation, chest pain, loss of smell (anosmia), and sweating. Chronic exposure may lead to severe health consequences, including premature death.¹²

An ammonia leak occurred on April 17, 2024, at approximately 11:40 p.m. inside the ice factory in Bang Lamung District, Chonburi Province, causing ammonia to leak into the surrounding communities. Many individuals experience symptoms such as throat, suffocation, and eye irritation. Governmental officers were able to control the situation by 2:55 a.m., with several workers and nearby residents being affected. On the day of the incident, a total of 63 patients were taken to the hospital, with 160 people affected by ammonia, including 9 in serious conditions.¹³

Most ice factories are small operations with fewer than 50 workers, which means that occupational health and safety may not be systematically managed. As a result, safety oversight is often inadequate, with no specific supervisor, professional safety officers, or safety committees in places, as per the Labor Law of 2022.¹⁴ Therefore, the purpose of this study is to analyze the root causes of ammonia leakage in an ice factory using Fault Tree Analysis (FTA) techniques. In the subsequent section, risk assessment is conducted based on the criteria established by the Department of Industrial Work, which serves as a guideline for developing control measures to prevent future chemical leak incidents.

2. Methods

The research team collaborated with industry representatives to investigate the cause of an ammonia leak at an ice factory in Chonburi Province. On May 14, 2024, the team conducted interviews with ice factory executives and administered a survey. The collected data were subsequently used to write a report and perform a Fault Tree Analysis (FTA). This research is a survey-based study that utilizes event analysis through a top-down approach, following deductive logic. The analysis begins with the first event (Top Event), and subsequently identifies the causes at the next level of sub-events (Intermediate Event). The process continues until the root cause of the sub-event (Basic Event) is identified, which typically results from the machinery or equipment failure or human errors . The research employs tree chart analysis techniques in accordance with the regulations of Department of Industrial Work, focusing on the criteria for hazard identification, risk assessment, and risk management outlined in the B.E. 2543 (2000) plan.¹⁵

2.1 Data collection and analysis

1. The initial or top event was defined as an ammonia leak in Bang Lamung District, Chonburi Province.
2. A fault tree analysis was conducted to identify the causes, starting with the initial event, and to systematically analyze the contributing factors. The analysis followed the symbols and guidelines outlined by the Department of Industrial Work (2000) as detailed in Table 1. This process continued until the root cause (basic event) was identified.
3. The root cause of the problem was determined by assigning symbols to each gate and eliminating duplicate basic events using Boolean Algebra’s law.
4. The identified problem or root cause were then prioritized.
5. After the prioritization, the risk assessment considers both the probability of hazard and their severity through hazard identification. The probability of events is classified into four levels based on their frequency of occurrence, as shown in Table 2. The severity of impacts on people, the community, property and the environment is outlined in Table 3. The risk level is determined by multiplying the probability level by the severity level. In case where the severity affects different factors (people, the community, property, and environment) at varying levels, the highest severity level should be selected. The risk level can then be classified into fours level, as detailed in Table 4.

Table 1. Symbols used in risk assessment by FTA techniques.¹⁶

Event symbols	Name	Description
	And Gate	Events occur because of the causes of every sub-event
	Or Gate	An event can occur due to any one of the sub-causes
	Basic Event	Events can happen normally. There is no need to do a root cause analysis
	Fault Tree Event	Sub-events that result in a chain of events until causing an accident
	Underdeveloped Event	An event that does not require further analysis to find the cause because there is no supporting information
	External Event	External events or external factors that cause various events

Table 2. Probability level of event.

Level	Description
1	Low chance of occurrence, unlikely to occur within 1 year or more
2	Low chance of occurrence, with a frequency of 1 time within 6 months to 1 year
3	Moderate chance of occurrence, with a frequency of 1 time within 1-5 months
4	High chance of occurrence, with a frequency of more than 1 time per month

Table 3. Severity ranking according to the criteria of the Department of Industrial Works.

Level	Severity	Description
Level	Severity	People	Community	Environment	Property
1	Low	Minor injuries at first aid level	Minor impact on the surrounding community of the factories	Minor environment impact, controllable or resolvable	Minor property damage (less than 50,000 baht), controllable or resolvable
2	Medium	Injury requiring medical treatment	Impact on the surrounding community of the factory resolvable within 7 days or 1 week	Moderate environment impact resolvable within 7 days or 1 week	Moderate property damage allowing production to continue, with costs between 50,000 and 100,000 baht
3	High	Serious injury or illness.	Impacting surrounding community of the factory resolvable within 7 to 14 days	Severe environment impact, requiring control or resolution within 7 to 30 days	Massive property damage necessitating the shutdown of operational units, with costs between 100,000 and 200,000 baht
4	Extreme	Disabled or dead	Severe impact on the surrounding community and large area, required government assistance for more than 1 month	Extreme environmental impact, requiring extensive time and resources for control or resolution, exceeding 1 month	Extensive property damage halting all production, exceeding 200,000 baht

Table 4. Risk level.

Level	Multiplication product	Description
1	1-2	Low risk
2	3-6	Acceptable risk, requiring revision of control measures
3	8-9	High risk, requiring action to reduce risk
4	12-16	Unacceptable risk, requiring a cessation of operations

2.2 Process description

In the ice cube production process, the first step involves passing raw water through the conditioning stage. Water is pumped from rivers or groundwater sources into sedimentation ponds. After sedimentation, the water filter and its conditions were adjusted. In the ice production unit, the conditioned water from the storage tank is transferred into template molds, which are maintained at a low temperature of approximately -4 to -8 ^oC. It takes approximately 48 h (2 days) for the entire volume to freeze into the ice cube. After this period, the water in the mold was completely frozen. To remove the ice, the mold was removed from the brine pond and submerged in water, causing the ice to adhere to the mold’s surface and melt slightly. This allows ice cubes to be released from the envelope. The ice cubes were stored in a cold room until they were ready for distribution or sale. The block flow diagram and cooling system process for producing ice cubes using ammonia are shown in Figures 1 and 2, respectively.

Figure 1. Block flow diagram of ice production process.

Figure 2. The cooling system process for producing ice cubes.

3. Results and discussions

3.1 Basic cause analysis of ammonia leakage

Figure 3 illustrates the analysis of an ammonia accident from an ice manufacturing facility located in Banglamung, Chonburi Province, using fault tree analysis (FTA). As shown in Figure 3, the primary causes of ammonia leakage are failure of the evaporative condenser and human error. The evaporative condenser failure may result from a broken fan, damaged ammonia transport pipe, or low cooling water level. A broken fan could be caused by a malfunctioning fan motor or dust clogging of the system. Ammonia transport pipes may be damaged by factors such as pipe deterioration, inadequate insulation, material stress, or the use of non-standard pipes. A low coolant level is typically attributed to a non-working pump or clogged cooling pad. Pump failure can result from issues such as using the wrong type of motor shaft bearing, non-heat-resistant lubricants, broken copper coils, and lack of maintenance. Human error can also contribute to leaks, often owing to a shortage of skilled technicians and the absence of daily inspections. In addition, inappropriate environmental conditions, such as insufficient lighting, uneven walkways, and the lack of an inspection system, can worsen the problem. The primary cause of ammonia leakage was identified using Boolean principles, which are placed at the top of the diagram. Sub-events are represented by rectangles (labeled W₁ to W₉), while basic events are depicted by circles (labeled A-O).

Figure 3. Tree structure diagram illustrating of hazard identification using fault tree analysis (FTA) technique.

Boolean algebra Equations

(1)

T = {W_{1}}^{*} W_{2}

(2)

W_{1} = W_{3} + W_{4} + W_{5}

(3)

W_{2} = L + W_{8}

(4)

W_{3} = A + B

(5)

W_{4} = C + D

(6)

W_{5} = W_{6} + W_{7}

(7)

W_{6} = E + F + G

(8)

W_{7} = H + I + J + K

(9)

W_{8} = {W_{9}}^{*} (O)

(10)

W_{9} = M^{*} N

(11)

T = (A + B + C + D + E + F + G + H + I + J + K) (L + MNO)

(12)

= AL + BL + CL + DL + EL + FL + GL + HL + IL + JL + KL, + AMNO + BMNO + CMNO + DMNO + EMNO + FMNO + GMNO + HMNO + IMNO + JMNO + KMNO

By substituting Equation (1) with Equations (2)–(10), we obtained the value in Equation (11). According to Equation (12), ammonia leakage can occur in 22 scenarios in total.

3.2 Prioritization

The risk assessment of the underlying causes of ammonia leak in Chonburi Province, using the Department of Industrial Works criteria, should consider the basic cause collectively. The criteria for considering which cause is most likely to result in accidents prioritize accordingly. If contains only one event, the minimum cut set is considered before the set containing two or three events. If multiple sets have the same number of basic events, human error is prioritized first, followed by active equipment failure, and then passive equipment failure. Table 5 summarizes the basic causes, number of events, and priorities. All 22 scenarios were ranked according to their level of importance. The scenarios ranked first in importance are 4,5,8, and 9; those ranked second are 1, 3, 6, 7, 10, and 11; those ranked third are 3, 13, 15, 16, 19, and 20; and those ranked fourth are 12, 14, 17, 18, 21 and 22, respectively.

Table 5. The primary cause, type of failure, and priority.

Scenario	Primary cause	Failure type	Priority	Scenario	Primary cause	Failure type	Priority
1	A,L	P,H	2	12	A,M,N,O	P,P,A,H	4
2	B,L	A,H	1	13	B,M,N,O	A,A,A,H	3
3	C,L	P,H	2	14	C,M,N,O	P,P,A,H	4
4	D,L	A,H	1	15	D,M,N,O	A,A,A,H	3
5	E,L	A,H	1	16	E,M,N,O	A,A,A,H	3
6	F,L	P,H	2	17	F,M,N,O	P,P,A,H	4
7	G,L	P,H	2	18	G,M,N,O	P,P,A,H	4
8	H,L	A,H	1	19	H,M,N,O	A,A,A,H	3
9	I,L	A,H	1	20	I,M,N,O	A,A,A,H	3
10	J,L	P,H	2	21	J,M,N,O	P,P,A,H	4
11	K,L	P,H	2	22	K,M,N,O	P,P,A,H	4

3.3 Risk assessment

Risk assessment is a process that analyzes the factors considering the likelihood and severity.

The consideration of hazard likelihood involves identifying equipment failures and human errors in operation. For hazard severity, data from identification hazards are used to assess the severity level and to evaluate the potential impact on people, property, community, and the environment. Table 6 presents the risk assessment and corresponding levels derived from the prioritization section. It was found that scenarios 2, 5, 8, and 9 exhibited the highest likelihood of occurrence, as these scenarios were anticipated to occur once every to 1-5 years. Conversely, scenarios 2 and 12 demonstrated the lowest likelihood, with occurrence expected once every five to ten years. For severity assessment, scenarios 4, 8, 9, and 12 showed the highest severity (level 3) because of their significant impact on worker injuries and severe illnesses, as well as their effects on the factory, property, environment, and interruptions in ice production. For scenarios 2 and 5, the severity is classified as moderate (level 2) because of the potential for worker injuries, which require a short time to mitigate their impact on the factory, community, property, and environment. Consequently, ice production can be continuous without significant interruption. The results from the risk assessment indicate that scenarios 8 and 9 are classified as high-risk levels, whereas scenarios 2,4, 5, and 12 are classified as moderate levels. According to the Department of Industrial Work regulation on hazard classification, risk assessment and management operations with high-risk levels must be halted for improvements and maintenance. As shown in Table 3, the use of an improper bearing type and a lubricant lacking heat resistance necessitates the adoption of standard bearings in the pump and the application of heat-resistant lubricants to minimize pump damage and maintain adequate cooling levels. In addition, moderate-risk levels, such as accumulation of dust, absence of pipe insulation, and fouling of the evaporator cooling pad, should be addressed through inspection, cleaning, and maintenance every two months. Training and reskilling are required to enhance worker knowledge and expertise.

Table 6. Suggestion and risk assessment of ammonia leak accident.

Scenario	Hazard or consequences	Preventive measures and control/suggestion	Risk assessment
			Likelihood	Severity	Risk level
2	Accumulation of dust obstructing the fan functionality	- Inspection and maintenance fan - Cleaning the fan bland every 2 months	3	2	6 (Moderate)
4	Absence of insulation pipe	- Implementation of pipe insulation - Inspection every 2 months	2	3	6 (Moderate)
5	Fouling of the evaporators cooling pad	- Inspection and maintenance - Cleaning the evaporator and cooling pad	3	2	6 (Moderate)
8	Utilization of an incorrect bearing type	- Used the standard bearing - Assess the efficiency of bearing and pump - Inspection every 2 months	3	3	9 (High)
9	Used of a lubricant that lack heat resistant	- Used heat-resistant lubricants	3	3	9 (High)
12	The worker lacks necessary knowledge and expertise	- Provide training to worker - Training every 6 months	2	3	6 (Moderate)

4. Conclusion

The fault tree analysis was applied to identify the basic events of ammonia leakage during ice manufacturing, and a risk assessment was conducted. The conclusions of this study are as follows:

• FTA identified 22 scenarios related to ammonia leakage. Among these, scenarios, 2,4,5,8, and 12 are prioritized as the most critical.
• The risk assessment revealed that ammonia leakage from evaporative condenser failure, caused by the use of nonstandard bearings and improper lubricants, is classified as high-risk.
• Additionally, fan failure and damage to ammonia transport pipes resulting from dust accumulation and the absence of pipe insulation, respectively, were identified as medium risks.
• To address these high-risk issues, ice production equipment should be upgraded to meet standards and subjected to regular inspection and maintenance to prevent ammonia leakage.
• Implementing safety training programs on the use, storage, packaging, and transport of ammonia, as well as proper equipment and operation in ice production, will help mitigate future ammonia leakage.

Ethics and consent

Ethical approval were not required. We would like to confirm that we have received written consent from the interviewees to provide information regarding the ammonia leak in the ice plant.

Data availability

Underlying data

Figshare: Risk assessment of ammonia leakage by fault tree analysis: Case study in the ice manufacture, Chonburi Province. https://doi.org/10.6084/m9.figshare.27979271.¹⁷

This project contains the following underlying data:

• Underlying data.xlsx. (Causes of ammonia leaks and labels and equipment failure image)
Data are available under the terms of the Creative Commons Attribution 4.0 International license (CC-BY 4.0).

Extended data

Figshare: Risk assessment of ammonia leakage by fault tree analysis: Case study in the ice manufacture, Chonburi Province. https://doi.org/10.6084/m9.figshare.28068950.¹⁷

This project contains the following extended data:

• Extended data_Interview guides_English
• Extended data_Interview guides_Thai
Data are available under the terms of the Creative Commons Attribution 4.0 International license (CC-BY 4.0).

Acknowledgments

The author would like to thank the Faculty of Public Health, Burapha University, for the research fund.

References

1. Division of Occupational and Environmental Diseases, Ministry of Public Health: Chemical Accident Report: 2024.2024. Accessed July 20, 2024. Reference Source
2. Chen L, Liu B, Pang L, et al.: Effect of ammonia environment on the quality of boxed non-dairy cream. Int. J. Refrig. 2024; 165: 351–359. Publisher Full Text
3. Cheng C, Tan W, Liu L: Numerical simulation of water curtain application for ammonia release dispersion. J. Loss Prev. Process Ind. 2014; 30: 105–112. Publisher Full Text
4. Khudhur DA, Tuan Abdullah TA, Norazahar N: A Review of Safety Issues and Risk Assessment of Industrial Ammonia Refrigeration System. ACS Chem. Health Saf. 2022; 29(5): 394–404. Publisher Full Text
5. Purnama R, Syafrudin S, Huboyo H: The Potential Impact Analysis of Ammonia Gas Leakage On Refrigeration System Using Aloha Software (Case Study At PT. Cahaya Gunung Foods). IOP Conf. Ser. Earth Environ. Sci. 2020; 448: 012103. Publisher Full Text
6. Anjana NS, Amarnath A, Harindranathan Nair MV: Toxic hazards of ammonia release and population vulnerability assessment using geographical information system. J. Environ. Manag. 2018; 210: 201–209. PubMed Abstract | Publisher Full Text
7. Hu L, Niu J, Wu W, et al.: Quantitative analysis of toxicity risks in the operation of ammonia-fueled tugboats. Ocean Eng. 2024; 310: 118759. Publisher Full Text
8. Department of Industrial Works, Ministry of Industry: Handbook for the Management of High Hazardous Chemicals: Ammonia.2010. Accessed June 15, 2024. Reference Source
9. Tan W, Lv D, Guo X, et al.: Accident consequence calculation of ammonia dispersion in factory area. J. Loss Prev. Process Ind. 2020; 67: 104271. Publisher Full Text
10. Ng CKL, Liu M, Lam JSL, et al.: Accidental release of ammonia during ammonia bunkering: Dispersion behaviour under the influence of operational and weather conditions in Singapore. J. Hazard. Mater. 2023; 452: 131281. PubMed Abstract | Publisher Full Text
11. Yarandi MS, Mahdinia M, Barazandeh J, et al.: Evaluation of the toxic effects of ammonia dispersion: consequence analysis of ammonia leakage in an industrial slaughterhouse. Med. Gas Res. 2021; 11(1): 24–29. PubMed Abstract | Publisher Full Text | Free Full Text
12. Changphuek S, BoonglaY.: Modeling of Dangerous Chemical Leaks: A Case Study of Butyl Acetate. Thai J. Saf. Health. 2023; 16(2): 65–81.
13. Rath T: Ammonia leaks at Bang Lamung Ice Factory.2024. Accessed June 15, 2024. Reference Source
14. Siamsafety: Duties of Safety Officers at Each Level.2022. Accessed June 15, 2024. Reference Source
15. Department of Industrial Works: Criteria for hazard identification, risk assessment, and establishment of risk management plan B.E. 2543 (2000).2000. Accessed July 10, 2024. Reference Source
16. Pahasup-anan T, Kreetachat T, Ruengphrathuengsuka W, et al.: Dust Explosion Risk Assessment of Extruded Food Production Process by Fault Tree Analysis. ACS Chem. Health Saf. 2022; 29(1): 91–97. Publisher Full Text
17. Nakyai T, Phatrabuddha S, Homsri P, et al.: Risk assessment of ammonia leakage by fault tree analysis: Case study in the ice manufacture, Chonburi province. [Dataset]. Figshare. 2024. Publisher Full Text

Comments on this article Comments (0)

Version 1

VERSION 1 PUBLISHED 12 Feb 2025

Author details Author details

¹ Industrial Hygiene and Safety, Burapha University, Mueang Chonburi District, Chon Buri, Thailand
² Process and Industrial Engineering, Mahanakorn University of Technology, Bangkok, Bangkok, Thailand

Teeranun Nakyai
Roles: Conceptualization, Methodology, Writing – Original Draft Preparation

Sujee Phatrabuddha
Roles: Conceptualization, Investigation, Methodology

Patomphong Homsri
Roles: Conceptualization, Investigation, Methodology, Resources

Nantaporn Phatrabuddha
Roles: Conceptualization, Methodology, Writing – Review & Editing

Competing interests

No competing interests were disclosed.

Grant information

This research project was supported by a grant (ID 02/2566) from the Public Health, Burapha University, Thailand .
The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Article Versions (1)

version 1

Published: 12 Feb 2025, 14:192

https://doi.org/10.12688/f1000research.159905.1

Copyright

© 2025 Nakyai T et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Download

Export To

metrics

	Views	Downloads
F1000Research	-	-
PubMed Central Data from PMC are received and updated monthly.	-	-

Citations

0

SEE MORE DETAILS

CITE

how to cite this article

Nakyai T, Phatrabuddha S, Homsri P and Phatrabuddha N. Risk assessment of ammonia leakage by fault tree analysis: Case study in the ice manufacture, Chonburi province [version 1; peer review: 1 approved with reservations]. F1000Research 2025, 14:192 (https://doi.org/10.12688/f1000research.159905.1)

NOTE: If applicable, it is important to ensure the information in square brackets after the title is included in all citations of this article.

track

receive updates on this article

Track an article to receive email alerts on any updates to this article.

Open Peer Review

Version 1

VERSION 1

PUBLISHED 12 Feb 2025

Views

18

Reviewer Report 04 Mar 2025

Arroon Ketsakorn, Thammasat University, Bangkok, Bangkok, Thailand

Approved with Reservations

https://doi.org/10.5256/f1000research.175697.r367487

According to the title, the manuscript describes risk assessment by applying the fault tree analysis in the ice manufacturer in Chonburi province. Partly due to language issues, the manuscript is not easy to read and understand, especially regarding the fault ... Continue reading

According to the title, the manuscript describes risk assessment by applying the fault tree analysis in the ice manufacturer in Chonburi province. Partly due to language issues, the manuscript is not easy to read and understand, especially regarding the fault tree analysis. It is unclear how to use both fault tree analysis and risk assessment. Why did the authors choose to use those tools? However, this study has many good and important aspects but the manuscript needs some major, but I view, very “do-able” revisions.
Title

Please remove one letter from the address for Bangkok.

Abstract
-
Introduction

Please update the accident statistics by 2024
Please support the ammonia leak accident at factory with citations or literature sources when elaborating the aspects. This is an important step to find out the gap of research.
What is the gap of research? Because FTA is a tool that is already used for accident analysis.
Please send the manuscript to a native speaker to check before submission.
What are the advantages and disadvantages of using FTA?
Why did the authors choose the fault tree analysis? Please provide supporting reasons.

Objective
-
Methods

What kind of risk assessment does this research provide? Probabilistic risk assessment or quantitative risk assessment
How do the authors or teams identify human errors because human error do not have the reliability. Please give me details.
Please add the citation in Table 2-4
Please add more details on how to calculate the top event or undesired event
How do the authors prove the FTA diagram? Please add the details
Please specify the key qualifications or experience of the FTA team.

Results

Please give an example of manual calculation for FTA including minimal cut set

Discussion

The results should be discussed in the FTA section and risk assessment.
The discussion part should not be written in duplicate with the results of the study.
Authors must first discuss the study's findings and then explain how the study's results are similar or different from other studies.

Conclusion

The conclusion should not be written in duplicate with the results of the study.

References

Harmonize format with F1000Research style requirements.

Is the work clearly and accurately presented and does it cite the current literature?

Partly
Is the study design appropriate and is the work technically sound?

Partly
Are sufficient details of methods and analysis provided to allow replication by others?

Partly
If applicable, is the statistical analysis and its interpretation appropriate?

Partly
Are all the source data underlying the results available to ensure full reproducibility?

Yes
Are the conclusions drawn adequately supported by the results?

Partly

Competing Interests: No competing interests were disclosed.

Reviewer Expertise: Occupational health and safety

I confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard, however I have significant reservations, as outlined above.

CITE

Report a concern

Respond or Comment

Comments on this article Comments (0)

Version 1

VERSION 1 PUBLISHED 12 Feb 2025

Open Peer Review

Reviewer Status

Reviewer Reports

	Invited Reviewers
	1
Version 1 12 Feb 25	read

Arroon Ketsakorn, Thammasat University, Bangkok, Thailand

Comments on this article

All Comments(0)

Add a comment

Sign up for content alerts

Browse by related subjects

Back to all reports

Reviewer Report

18 Views

04 Mar 2025 | for Version 1

Arroon Ketsakorn, Thammasat University, Bangkok, Bangkok, Thailand

18 Views Cite this report Responses(0)

Approved With Reservations

According to the title, the manuscript describes risk assessment by applying the fault tree analysis in the ice manufacturer in Chonburi province. Partly due to language issues, the manuscript is not easy to read and understand, especially regarding the fault tree analysis. It is unclear how to use both fault tree analysis and risk assessment. Why did the authors choose to use those tools? However, this study has many good and important aspects but the manuscript needs some major, but I view, very “do-able” revisions.
Title

Please remove one letter from the address for Bangkok.

Abstract
-
Introduction

Please update the accident statistics by 2024
Please support the ammonia leak accident at factory with citations or literature sources when elaborating the aspects. This is an important step to find out the gap of research.
What is the gap of research? Because FTA is a tool that is already used for accident analysis.
Please send the manuscript to a native speaker to check before submission.
What are the advantages and disadvantages of using FTA?
Why did the authors choose the fault tree analysis? Please provide supporting reasons.

Objective
-
Methods

What kind of risk assessment does this research provide? Probabilistic risk assessment or quantitative risk assessment
How do the authors or teams identify human errors because human error do not have the reliability. Please give me details.
Please add the citation in Table 2-4
Please add more details on how to calculate the top event or undesired event
How do the authors prove the FTA diagram? Please add the details
Please specify the key qualifications or experience of the FTA team.

Results

Please give an example of manual calculation for FTA including minimal cut set

Discussion

The results should be discussed in the FTA section and risk assessment.
The discussion part should not be written in duplicate with the results of the study.
Authors must first discuss the study's findings and then explain how the study's results are similar or different from other studies.

Conclusion

The conclusion should not be written in duplicate with the results of the study.

References

Harmonize format with F1000Research style requirements.

Is the work clearly and accurately presented and does it cite the current literature?

Partly
Is the study design appropriate and is the work technically sound?

Partly
Are sufficient details of methods and analysis provided to allow replication by others?

Partly
If applicable, is the statistical analysis and its interpretation appropriate?

Partly
Are all the source data underlying the results available to ensure full reproducibility?

Yes
Are the conclusions drawn adequately supported by the results?

Partly

Competing Interests

No competing interests were disclosed.

Reviewer Expertise

Occupational health and safety

I confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard, however I have significant reservations, as outlined above.

Respond to this report

Responses (0)

[1] 1. Division of Occupational and Environmental Diseases, Ministry of Public Health: Chemical Accident Report: 2024.2024. Accessed July 20, 2024. Reference Source

[2] 2. Chen L, Liu B, Pang L, et al.: Effect of ammonia environment on the quality of boxed non-dairy cream. Int. J. Refrig. 2024; 165: 351–359. Publisher Full Text

[3] 3. Cheng C, Tan W, Liu L: Numerical simulation of water curtain application for ammonia release dispersion. J. Loss Prev. Process Ind. 2014; 30: 105–112. Publisher Full Text

[4] 4. Khudhur DA, Tuan Abdullah TA, Norazahar N: A Review of Safety Issues and Risk Assessment of Industrial Ammonia Refrigeration System. ACS Chem. Health Saf. 2022; 29(5): 394–404. Publisher Full Text

[5] 5. Purnama R, Syafrudin S, Huboyo H: The Potential Impact Analysis of Ammonia Gas Leakage On Refrigeration System Using Aloha Software (Case Study At PT. Cahaya Gunung Foods). IOP Conf. Ser. Earth Environ. Sci. 2020; 448: 012103. Publisher Full Text

[6] 6. Anjana NS, Amarnath A, Harindranathan Nair MV: Toxic hazards of ammonia release and population vulnerability assessment using geographical information system. J. Environ. Manag. 2018; 210: 201–209. PubMed Abstract | Publisher Full Text

[7] 7. Hu L, Niu J, Wu W, et al.: Quantitative analysis of toxicity risks in the operation of ammonia-fueled tugboats. Ocean Eng. 2024; 310: 118759. Publisher Full Text

[8] 8. Department of Industrial Works, Ministry of Industry: Handbook for the Management of High Hazardous Chemicals: Ammonia.2010. Accessed June 15, 2024. Reference Source

[9] 9. Tan W, Lv D, Guo X, et al.: Accident consequence calculation of ammonia dispersion in factory area. J. Loss Prev. Process Ind. 2020; 67: 104271. Publisher Full Text

[10] 10. Ng CKL, Liu M, Lam JSL, et al.: Accidental release of ammonia during ammonia bunkering: Dispersion behaviour under the influence of operational and weather conditions in Singapore. J. Hazard. Mater. 2023; 452: 131281. PubMed Abstract | Publisher Full Text

[11] 11. Yarandi MS, Mahdinia M, Barazandeh J, et al.: Evaluation of the toxic effects of ammonia dispersion: consequence analysis of ammonia leakage in an industrial slaughterhouse. Med. Gas Res. 2021; 11(1): 24–29. PubMed Abstract | Publisher Full Text | Free Full Text

[12] 12. Changphuek S, BoonglaY.: Modeling of Dangerous Chemical Leaks: A Case Study of Butyl Acetate. Thai J. Saf. Health. 2023; 16(2): 65–81.

[13] 13. Rath T: Ammonia leaks at Bang Lamung Ice Factory.2024. Accessed June 15, 2024. Reference Source

[14] 14. Siamsafety: Duties of Safety Officers at Each Level.2022. Accessed June 15, 2024. Reference Source

[15] 15. Department of Industrial Works: Criteria for hazard identification, risk assessment, and establishment of risk management plan B.E. 2543 (2000).2000. Accessed July 10, 2024. Reference Source

[16] 16. Pahasup-anan T, Kreetachat T, Ruengphrathuengsuka W, et al.: Dust Explosion Risk Assessment of Extruded Food Production Process by Fault Tree Analysis. ACS Chem. Health Saf. 2022; 29(1): 91–97. Publisher Full Text

[17] 17. Nakyai T, Phatrabuddha S, Homsri P, et al.: Risk assessment of ammonia leakage by fault tree analysis: Case study in the ice manufacture, Chonburi province. [Dataset]. Figshare. 2024. Publisher Full Text

Risk assessment of ammonia leakage by fault tree analysis: Case study in the ice manufacture, Chonburi province

Abstract

Introduction

Methods

Results

Conclusions

Keywords

1. Introduction

2. Methods

2.1 Data collection and analysis

Table 1. Symbols used in risk assessment by FTA techniques.16

Table 2. Probability level of event.

Table 3. Severity ranking according to the criteria of the Department of Industrial Works.

Table 4. Risk level.

2.2 Process description

Figure 1. Block flow diagram of ice production process.

Figure 2. The cooling system process for producing ice cubes.

3. Results and discussions

3.1 Basic cause analysis of ammonia leakage

Figure 3. Tree structure diagram illustrating of hazard identification using fault tree analysis (FTA) technique.

(1)

(2)

(3)

(4)

(5)

(6)

(7)

(8)

(9)

(10)

(11)

(12)

3.2 Prioritization

Table 5. The primary cause, type of failure, and priority.

3.3 Risk assessment

Table 6. Suggestion and risk assessment of ammonia leak accident.

4. Conclusion

Ethics and consent

Data availability

Underlying data

Extended data

Acknowledgments

References

Comments on this article Comments (0)

Open Peer Review

Comments on this article Comments (0)

Open Peer Review

Reviewer Status

Reviewer Reports

Comments on this article

Browse by related subjects

Competing Interests Policy

Stay Updated

Table 1. Symbols used in risk assessment by FTA techniques.¹⁶