Analysis of accidents in chemistry/chemical engineering laboratories in Korea

This is the first study to statistically analyze all chemical laboratory accidents in South Korea during 2015–2021 to examine the relationship among accident types and causes, damage types, and damaged areas. The data included accidents with injury requiring treatment for more than three days, following the standards of the Act on the Establishment of Safe Laboratory Environment. Frequency analysis was conducted on the current status of each variable, and a cross‐tabulation analysis identified the associations among them. The results identified 1380 laboratory accidents, with 342 chemistry/chemical engineering accidents. Chemical accidents were categorized as fires, explosions, and spills according to accident type; spills exhibited the highest frequency (69.0%) and were mostly caused by inadequate handling of chemicals (62.5%). Most explosions (62.2%) and fires (52.2%) were caused by abnormal/runaway reactions. Burn damage was high in all accident types, especially spills (76.1%). The face was frequently damaged across all accident types, while explosions damaged multiple areas. Several safety management measures are proposed to prevent/reduce spills, explosions, fires, and damage based on the results. The results can help researchers develop new protective technologies for safety in chemistry/chemical engineering laboratories.

[3] The absence of a central management system has been an obstacle to developing research on laboratory safety and related topics.
Moreover, the absence of laboratory accident investigations and statistical databases has been a serious problem in laboratory safety research, particularly in identifying laboratory risk factors and developing preventive measures.Therefore, laboratory safety experts in the United States have insisted on establishing a central management organization for laboratory accident management. 4ience and technology in Korea have developed rapidly since the mid-to-late 1960s, with intensive government support.However, the level of safety has failed to keep up with the development of science and technology, and many side effects of numerous laboratory accidents have been observed.In particular, unfortunate personal accidents have continued to occur, including the Seoul National University explosion accident in 1999 (three deaths), the KAIST explosion accident in 2003 (one death), and the Gyeongsan University explosion accident in 2005 (five injuries).
In response to continuous laboratory accidents, the Korean government enacted the Act on the Establishment of Safe Laboratory Environment (AESLE) in 2005 and introduced a nationwide central safety management system for laboratories.This Act is the first (worldwide) to enshrine laboratory safety as a national law.The AESLE consists of a total of eight chapters and stipulates the establishment of a safety management organization, as well as the implementation of various obligations related to safety inspection, safety education, accident compensation and insurance, health checkups, and accident reporting.Although the enactment of the AESLE reflected the harsh reality of laboratory safety in Korea at that time, the level of laboratory safety in Korea has continued to develop.Additionally, by systematically collecting laboratory accident data, it has been possible to secure basic data for conducting various studies related to laboratory safety.
The Korean AESLE stipulates the safety of all research activities and the protection of researchers in science and technology, including chemistry/chemical engineering, biology, machinery, electricity/electronics, energy, environment, medicine, and architecture.Since each research field has different risks depending on the characteristics of research activities, safety management suitable for the risk characteristics of the research field is required.For example, in the field of machinery, accidents such as cutting, trapping, and tightening of the body can occur while using cutters, drill machines, and processing equipment. 5,6In biology and medicine, pathogenic infections comprise a typical type of accident. 7,8In the electrical/electronic field, electric shock or fire owing to electric leakage may happen. 9,10In the chemistry/chemical engineering fields, chemical spills, explosions, and fire accidents may occur. 11,12Among these various research fields, the chemistry/chemical engineering field, in particular, requires a high level of safety management because of the high possibility of personal injury and property damage in the event of an accident, depending on the physical and chemical properties of the substances involved.
However, compared with these risks, many researchers perceive chemistry/chemical engineering laboratories as relatively safe. 13This perception is based on the general idea that the risks are low because of the small quantities of chemicals used in laboratories (i.e., only a few liters), compared with those used in industrial facilities.However, even if the quantities of chemicals used in the laboratory are lower than those used in the industrial field, chemical safety should be a concern, given such substances' inherent hazards (toxicity, flammability, and explosiveness).Laboratories, in particular, use chemicals to create and identify new chemical reaction mechanisms, posing the risk of accidents due to unpredictable and unsafe chemical reactions.In addition, since most laboratories are inside buildings, chemical accidents in small indoor spaces are highly likely to cause direct personal injuries to researchers.The University of California, Los Angeles explosion accident in 2009 is a representative example of such laboratory risks.Thus, many safety researchers have conducted studies for decades, examining safety processes in chemical laboratories, training curricula, system construction, and accident analysis to prevent laboratory accidents.For instance, Palluzi analyzed major safety issues in the laboratory and suggested preventive measures. 14Schröder et al.
compared and evaluated the safety levels of researchers in academic institutions, as well as the government and industrial sectors via a survey and analyzed the differences. 15Gopalaswami and Han examined various accident types and causes by analyzing the characteristics of accidents in the laboratory. 16However, most studies had limitations because they utilized statistical surveys limited to one laboratory or a few institutions, as well as informal or limited accident databases.
Therefore, conducting research that utilizes comprehensive laboratory accident databases has become necessary.
Hence, this study statistically analyzed all chemistry laboratory accidents in Korea from 2015 to 2021.It is the first laboratory chemical accident analysis based on laboratory accident investigation officially conducted nationally.Chemical accident data cover all accidents with accidental injury requiring treatment for more than three days, following the standards for reporting and receiving accidents stipulated in the AESEL.For data analysis, frequency analysis of the current status of each variable based on accident type, accident cause, damage type, damaged area, and cross-tabulation analysis was conducted to identify the association among variables.

| Acquisition of statistical data
According to the laboratory accident database used in this study, 1380 laboratory accidents were reported between 2015 and 2021 under the AESEL.This law stipulates that casualties requiring treatment for more than three days should be reported to the Korean government (Ministry of Science and ICT).Therefore, near misses without casualties are not included in the database.Additionally, among the reported accidents, those caused by occupational diseases that are difficult to identify as an apparent cause of the accident, such as leukemia, or for which it is difficult to derive associations among the variables were excluded from the analysis.

| Definitions
The laboratory accident investigation of the AESEL includes data on the date and time of the accident, location, situation, and personal injury status.Therefore, the classification criteria for data analysis were established based on the accident investigation table reported from the institution where the accident occurred.The classification criteria of this study were set as accident cause, accident type, damage type, and damaged area, in consideration of the characteristics of laboratory chemical accidents.The definitions of each variable are listed in Table 1.
Specifically, the accident type was classified into three categories, spills, fires, and explosions, which are used in numerous chemical accident analysis studies.The accident causes were classified into human and technical errors, based on the classification system of the accident causes for industrial accidents, and then categorized into four subtypes: inadequate handling of chemicals, misuse/nonuse of protective equipment, abnormal/runaway reactions, and research equipment defects.Based on the damage types of industrial accidents, a total of six damage types were set: burn, trauma, skin disease, asphyxiation, vision impairment, and complex damage.Additionally, the damaged areas were classified into face, arms, legs, and respiratory system, while damage to more than two areas was classified as multiple areas.
However, since the laboratory accident statistics used in this study do not provide quantitative damage information classified as severe or mild injuries, no discussion was conducted on the relationship between the cause or type of the accident and the degree of quantitative damage.

| Statistical data processing
Based on the classification system for laboratory accident data, defined above, SPSS 25.0 software was used, and the following analysis methods were performed.First, frequency analysis was performed to present the trend in laboratory accidents; using these results, we performed a comparative analysis with the previously published literature on laboratory safety.Second, cross-tabulation analysis T A B L E 1 Variable classification and definitions.

Laboratory accident
According to the Act on the Establishment of Safe Laboratory Environment in Korea: An accident in which a causality requiring treatment for more than three days occurred in a laboratory   on the application of new materials and convergence with other fields is being actively conducted. 17,18Therefore, in addition to chemical substance management in chemistry/chemical engineering laboratories, a wide range of measures may be required for radiation, work management, electrical and electronic, and mechanical accident prevention.

Cause of accident
9 The difference in accident types between laboratories and industrial sites can be interpreted based on the different risk characteristics of laboratories and industrial sites.For example, since laboratory glassware or prototype research equipment used in laboratories does not have a safety device such as a fail-safe structure widely used in industrial sites, there are differences in risk characteristics that make it difficult to prevent the spills of chemicals in the event of an abnormal reaction.A more detailed analysis is presented in Section 3.4.
Additionally, the trend in the frequency of accidents (by accident type) is similar to that of 128 chemical-related laboratory accidents, reported by Gopalaswami and Han to have occurred in universities and secondary educational institutions, published in the media from 2012 to 2015. 16Although there are numerical differences in the rate of occurrence for each accident type, we must underscore that the accident types in laboratory settings differ from the ones in the industrial sector.Thus, it is suggested that the development of safety standards that reflect the risk characteristics of laboratory settings is required, rather than the application of safety standards used in the industrial sector.
Figure 3B shows the frequency of laboratory accidents according to their cause.3C), the rate of human errors (inadequate handling of chemicals, misuse/ nonuse of protective equipment) was 61.7%, which was higher than that of technical errors.
To investigate the characteristics of personal injury, the casualty rates according to the type and cause of the accident were calculated (Table 3).The instances of casualties from spill, explosion, and fire accidents were 176, 45, and 29, respectively, amounting to 250 casualties and an average casualty rate of 126% per accident.Furthermore, when calculating the casualty rate based on the cause, it was found that accidents caused by research equipment defects exhibited a 190% rate, thus demonstrating the highest risk of personal injuries.
These results suggest a high likelihood of more than one casualty in the event of a laboratory accident.Therefore, of 196 chemical accidents, those that caused many casualties were extracted, analyzed, and listed in Table 4.
In the Korean laboratory accident database, 23 (11.7%) of 196 accidents resulted in more than one casualty.Additionally, the casualty rate was calculated as 334.7% per accident.As a result of identifying the casualty rate caused by accidents with multiple casualties, the rate for accidents involving research equipment defects was considerably high, at 800%.In the analysis by accident type, the casualty rate in the event of a spill accident was highest, at 407%.Therefore, it can be assumed that accidents involving research equipment defects and spill accidents have a high risk of causing multiple casualties.

| Analysis of the association between the types and causes of accidents in chemistry/chemical engineering laboratories
To determine the association between accident types and causes, Guidelines for Risk Based Process Safety can be used as an important tool for predicting unexpected events in research activities. 21ditionally, the small-scale Dewar vessel test-based reactivity screening technique 22 or the Risk Analysis Screening Tool (RAST) software, provided by the Center for Chemical Process Safety, can be applied to conduct risk analysis before chemical experiments. 23ditionally, Table 5 summarizes the chemical reactions and risks of sulfuric acid, nitric acid, hydrochloric acid, and hydrogen peroxide that are expected to prevent explosions and fire accidents due to abnormal/runaway reactions.
The causes of the abnormal/runaway reaction can also be assumed to be induced by vigorous chemical reactions using an auto- clave.An autoclave is a device designed as a closed system with a F I G U R E 4 Analysis of the association between types and causes of chemical accidents in chemistry/chemical engineering laboratories (cross-tabulation analysis results).
double-chamber structure generally made of metal, with sufficient structural safety to allow a vigorous chemical reaction under hightemperature and high-pressure conditions.Therefore, the use of an autoclave has led researchers to design more vigorous chemical reactions because they can overcome the energy barrier of chemical reactions that cannot be induced under normal conditions (i.e., normal pressure, room temperature), breaking the limits of the physical and chemical properties of the material itself and allowing the reaction to proceed.However, the possibility of an explosion accident can be significantly increased if the researcher conducts an experiment that exceeds the performance limit of an autoclave without considering the temperature and pressure that may occur in these vigorous chemical reactions, or if they use an autoclave without an appropriate safety device (e.g., safety valve, temperature, and pressure monitoring).Thus, when inducing a chemical reaction under high-temperature/highpressure conditions using an autoclave, risk assessment and appropriate safety device construction should be performed to prevent an explosion.

| Analysis of the association between accident types and damage in chemistry/chemical engineering laboratories
To determine the association between accident types and damage (types and areas), a cross-tabulation analysis was conducted using  F I G U R E 6 Analysis of the association between types of chemical accidents and damaged areas in chemistry/chemical engineering laboratories (cross-tabulation analysis results).
dissolve lipid membranes, causing injuries, whereas inorganic solutions cause burns through a denaturation mechanism. 24Burns caused by chemical reactions between human skin and chemicals are classified as chemical burns; they account for approximately 10.7% of all burn injuries and 30% of all burn deaths. 25Therefore, it should be noted that a spill accident in a laboratory can cause severe chemical burn damage to researchers.
In particular, the rate of burns in all accident types identified in the analysis is a concern.Analysis of damage types showed that the rate of burn damage was high in all accident types.Particularly, the rate of burn damage in spill accidents was 76.1%, and it was found that chemical substances caused chemical burns.In the analysis of the damaged area, the face was identified as the damaged zone at a similar rate in all accident types, and it was found that explosion accidents caused damage to multiple areas.Therefore, the following safety management measures are proposed.This study is the first analysis on chemical accidents in laboratories, based on official statistics at the national level in Korea; it can help researchers develop new protective technologies to ensure the safety of researchers in chemistry/chemical engineering laboratories.
However, we propose that further research is required to prevent chemical accidents by investigating and analyzing near misses in laboratory settings.

3 | RESULTS AND DISCUSSION 3 . 1 |
Figure 1A shows the current status of laboratory accidents in Korea's science and technology sector over the past seven years.Additionally, the number of laboratory accidents in Korea has continued to increase.As shown in Figure 1B, the number of laboratory accidents in 2018 exceeded 200 cases for the first time; 277 cases were recorded in 2021, the highest number since the investigation.This increase in accidents can be attributed to the growth in the research and development (R&D) scale and the quantitative increase in laboratories in Korea.

3. 2 |
Analysis of accidents in chemistry/chemical engineering laboratoriesIn Figure2A, 342 chemistry/chemical engineering laboratory accidents occurring between 2015 and 2021 are categorized and F I G U R E 1 Status of laboratory accidents in Korea (2015-2021).(A) Status of laboratory accidents by science and technical field, and (B) status of laboratory accidents by year.F I G U R E 2 Status of laboratory accidents in chemistry/chemical engineering laboratories.(A) Status of accidents by accident field, and (B) status of accidents by institution type.displayedby their cumulative percentages.As a result of identifying the occurrence rates of accidents in the chemistry/chemical laboratories, accidents caused by handling chemicals accounted for 57.3% of the sample (196 cases), and mechanical accidents caused using mechanical equipment accounted for 29.5% (101 cases).These accident rates by field reflect the convergence and diversity of the chemistry/chemical engineering research field.In chemistry/ chemical engineering, from basic experiments using laboratory glassware to pilot-scale production research through upscaling, research a cross-tabulation analysis was conducted using 196 chemical accidents; the results are shown in Figure4.The cross-tabulation analysis showed that X 2 = 72.612(df = 6, p = 0.000), indicating an association between variables.In the case of spill accidents, the accident rate due to inadequate handling of chemicals (62.5%) was high, whereas those for explosions and fires were 62.2% and 52.2%, respectively, indicating a high accident rate due to abnormal/runaway reactions.This result indicates that spill accidents are likely caused by human error (e.g., the inadequate handling of chemicals), whereas fire and explosion accidents are likely caused by technical errors (e.g., abnormal/ runaway reactions).Inadequate handling of chemicals, the leading cause of spill accidents, is a human error caused by researchers' carelessness.According to the accident report used in this study, most spill accidents occurred when some of the chemicals (mainly liquids) from a container came into contact with researchers' body while they were moving or subdividing the chemicals.These accidents do not cause severe damage, such as fire or explosion, but can lead to casualties owing to direct contact.Thus, it is thought that safety training to reduce human errors and periodic supervision by the laboratory manager are necessary to prevent spill accidents caused by the inadequate handling of chemicals.Abnormal/runaway reactions were identified as the leading causes of explosion and fire accidents (62.2% and 52.2%, respectively).Since accidents due to abnormal/runaway reactions are cases researchers do not predict in the experimental plan, direct preventive measures are limited.In particular, it is difficult to determine and predict risks because laboratories use unstandardized experimental processes and unverified chemicals.Moreover, safety devices such as F I G U R E 3 Analysis of chemical accident characteristics in laboratories by accident type and cause.(A) Results of frequency analysis by accident type, and (B) results of frequency analysis by accident cause.rupturedisks and safety valves to reduce damage during abnormal/ runaway reactions, mainly used in the industry sector, are unsuitable for small-scale research equipment due to structural and design constraints.As a countermeasure against this issue, researchers should identify and remove/block as many risk factors as possible by assessing risks; however, Ayi and Hon reported that most researchers do not conduct risk assessments.20Therefore, it is necessary to improve the skill of researchers in handling chemicals and implement risk assessments in the laboratory.In particular, various techniques established in the chemical industry can be applied to the hazard identification of abnormal/runaway reactions.For example, hazard identification and risk analysis (HIRA) according to

F I G U R E 5
Analysis of the association between types of chemical accidents and types of damage in chemistry/chemical engineering laboratories (cross-tabulation analysis results).

1 . 2 .
Prevention of spill accidents: Implementation of periodic safety training to reduce human errors.Prevention of explosion and fire accidents: Prediction of abnormal/runaway reactions by performing a risk assessment of research activities such as HIRA in the Guidelines for Risk Based Process Safety and RAST software.

3 .
Damage reduction: Wearing appropriate protective equipment and establishing damage reduction facilities to prepare against explosions.
Inadequate handling of chemicalsFailure to comply with research procedures and methods or performing work negligently; the researcher's unintentional negligence; research equipment or facilities are appropriate, but the researcher handles them recklessly BurnInjury to skin and tissues due to contact with flames, hot objects, or chemicals Trauma Fractures, sprains, amputations, stabs, wounds, lacerations, abrasions, etc. Skin disease Rashes, blisters, and hives (urticaria) on the skin Asphyxiation Convulsions, seizures, fatigue, loss of consciousness, chest pain, etc. Vision impairment Vision abnormality due to damage to the eyeball Complex Two or more types of damage Damaged area Face Head (skull, eyes, nose, ears, mouth) and neck Arms Shoulders, arms, hands Legs Toes, thighs, knees, ankles, feet Respiratory system Pulmonary and airway diseases Multiple areas Two or more body parts (Pearson's chi-square tests) was performed to identify the association among the variables using a 0.05 level of significance (p-value).
Accident rate analysis results by institution type.
T A B L E 3 Frequency of casualty rate by cause and type of chemical accident in chemistry/chemical engineering laboratories.Frequency of casualty rate by cause and accident type in chemical accidents with multiple casualties in chemistry/chemical engineering laboratories.
occurs in close proximity to the researcher.However, protective equipment such as safety glasses, lab coats, and gloves used in the laboratory is used to minimize physical contact with chemicals rather than protect from explosions.Hence, these protective equipment are unsuitable for research activities concerning explosions.Therefore, the safety of the researchers should be considered in chemical research in which an explosion accident is expected; accordingly, restrictive measures, such as safety barriers or separation of reaction facilities and control systems, should be implemented.This study examined the relationship between accident types, accident causes, damage types, and damaged areas by analyzing chemical accidents that occurred in chemistry/chemical engineering laboratories in Korea.From 2015 to 2021, 1380 laboratory accidents occurred; among them, 196 chemical accidents occurred in chemistry/chemical engineering laboratories.Chemical accidents were classified into fires, explosions, and spills according to the type of accident, with spill accidents exhibiting the highest frequency (69.0%).Additionally, cross-tabulation analysis between accident types and causes of accidents revealed that the leading cause of spill accidents was human errors due to the inadequate handling of chemicals (62.5%), whereas that of explosion and fire accidents was mechanical errors due to abnormal/runaway reactions (62.2% and 52.2%, respectively).
larly, explosions in chemistry/chemical engineering laboratories that mainly use laboratory glassware, such as flasks and condensers, can cause severe physical damage (trauma) to nearby researchers.Since explosions accompanied by sparks and flames can also cause burns, in addition to trauma such as cuts and stabs, they can be interpreted as the cause of complex damages.and damage to research equipment were considered the causes of trauma and complex damage.Thus, when the location of the explosion is close to the researcher, it can cause complex damage and damage to multiple areas.Additionally, even if the researcher wears protective equipment, an explosion is likely to cause damage that exceeds the protective performance of protective equipment if it