The Indonesian Journal of Occupational Safety and Health

2023, 12 SI(1): 1-11

p ISSN: 2301 8046, e ISSN: 2540 7872
http://doi.org10.20473/ijosh.v12iSI1.2023.1-11 ORIGINAL ARTICLE

Hazardous Area Classification Assessment at a Pharmaceutical Industry in East

Jakarta

Eky Susilowati1, Fatma Lestari1,2

1Departement of Occupational Health and Safety, Faculty of Public Health, Universitas Indonesia, Indonesia
Building C, 1st Floor Faculty of Public Health Universitas Indonesia, Depok, West Java 16424, Indonesia
2Disaster Risk Reduction Center, Universitas Indonesia, Indonesia

Integrated Laboratory and Research Center Building, 2nd floor Universitas Indonesia, Depok, West Java 16424, Indonesia

ABSTRACT
Introduction: Fire is a common risk in any industrial facility that uses combustible and flammable raw materials, products,
or supporting materials. Among others, the pharmaceutical industry is exposed to such risk due to the application of
flammable liquids including ethanol as a volatile solvent in production areas, which has the potential to form explosive
atmospheres through evaporation from pools created by accidental releases. Therefore, this study aims to analyze the
hazardous area classification (HAC) in ethanol storage areas to facilitate the execution of risk mitigation efforts for
reducing the role of ignition sources that cause fire and explosion. Methods: The HAC assessment was carried out in
December 2021 - January 2022 using the quantitative method outlined in the International Electrotechnical Commission
(IEC) standard: IEC/EN 60079-10-1 for zone determination. During flash point analysis, the ASTM D-93 method was
employed to define the class of ethanol as a flammable liquid. Results: The ethanol storage areas fell into the zone 2
category based on the secondary grade of release, as well as the areas’ ventilation effectiveness with a medium dilution,
and fair ventilation availability. The extent of zone 2 is up to 3 m from the release source. Conclusion: Ignition sources
capable of leading to fire and explosion incidents in ethanol storage areas should be controlled.

Keywords: ethanol storage, explosive atmosphere, hazardous area classification, IEC/EN 60079-10-1

Corresponding Author: electrical, including friction, heat impact, and heat

Fatma Lestari of reaction. The electrical ignition source is static
Email: fatma@ui.ac.id electricity and electric sparks. Out of the 68 fire
Telephone: +6281380685749 and explosion accidents that occurred from 2010
to 2016, static electricity accounted for 26 cases
INTRODUCTION (38%), and 13 cases (19%) were due to electric
Fire is a common risk in any industrial facility sparks (Jae, Chang and Lee, 2018). The electricity
that uses combustible and flammable raw materials, used in equipment and facilities must be managed
products, or supporting materials. In order for a fire properly to minimize the ignition potential. This
to occur, all three required elements, namely oxygen, requires careful equipment selection and installation,
combustible materials, and ignition sources, must as well as maintenance to guarantee their integrity
be satisfied. The combustible materials’ leakage and prevent the tendency of becoming a fire source.
together with the surrounding air (oxygen) often One way of reducing an ignition source potential in
leads to fire or explosion. Their ignition can cause a electrical equipment is to ensure they are designed
fire that will damage the facility with consequences and installed in accordance with the hazardous
including the threatening of workers' lives, and area.
business loss. Therefore, it is extremely important A hazardous area is defined as an area with a
to ensure taking special precautions to manage possibility of fire or explosion due to an available
the ignition source where such combustible or mixture of flammable and non-toxic gases or
flammable materials are used. Ignition sources substances capable of burning (Lestari et al., 2021).
can be classified into mechanical, chemical, and This requires special equipment and installation to

Cite this as: Susilowati, E. and Lestari, F.. (2023) ‘Hazardous Area Classification Assessment at a Pharmaceutical
Industry in East Jakarta’, The Indonesian Journal of Occupational Safety and Health, 12(SI1), pp. 1-11.

©2023 IJOSH All right reserved. Open access under CC BY NC–SA license doi:10.20473/ijosh.v12iSI1.2023.1-11
Received August 24, 2022; 1st revision November 16, 2022; 2nd revision November 27, 2022; Accepted December 22, 2022, Published:
February 2023. Published by Universitas Airlangga.
2 The Indonesian Journal of Occupational Safety and Health, Volume 12, Special Issue 1, February 2023: 1-11

protect against potentially flammable and explosive specification and installation of electrical/electronic
substances (Bahadori, 2014). equipment. Based on this, (Pal, 2019) determined
The hazardous area classification (HAC) is the classification of hazardous areas in acetone
carried out to provide a fire and explosion risk storage tanks in a pharmaceutical industry with
profile in an area. This cannot predict accurately respect to the source of release and ventilation.
that an explosion will occur, but only separates a The result of HAC recommended that electrical
facility area into several levels of fire and explosion equipment should not be used in zone 0 where the
possibilities, and it is a risk mitigation (Lestari et leak/release source is found inside acetone storage
al., 2021). tanks. Meanwhile, areas around the storage tanks
The HAC method is applied in classifying areas and their handhole/ventilation port as well as the
within an industrial facility that uses combustible dyke area are designated as zones 1 and 2 which
or flammable materials. It helps determine the require using only enclosed flameproof electrical
appropriate type of equipment for the areas to equipment. In this study, the extent of zones was
minimize potential ignition sources. HAC assessment determined, specifically zone 1 reached 1.5 m from
is the first step taken during the classification to the handhole/ventilation area, while zone 2 was 3 m
ensure proper equipment selection and installation. from areas surrounding the storage tanks and dyke
In the assessment process, release sources of (Pal, 2019).
hazardous chemicals such as flammable liquids, Besides acetone, ethanol is more widely
gases, vapor, and combustible dust are analyzed. employed in the pharmaceutical industry. Ethyl
This also includes determining the likelihood, alcohol, commonly known as ethanol is identical
quantity, and duration of leakage or release to in composition to potable alcohol. Ethanol with
evaluate ventilation effectiveness. Furthermore, HAC the molecular formula C2H6O is clear, colorless,
involves evaluating each area within an industry for volatile liquid with a pleasant smell prepared by
ventilation effectiveness and possible risk based on sugar fermentation (Onyekwelu, 2019). The vapor
the group of gases present and zones that require is combustible with air in proportions of 3.5-15%
electrical installations in compliance with IEC/EN (Guillaume et al., 2013).
60079-10-1 standards. Hazard zone classification for OSHA and National Fire Protection Association
flammable gas and liquid begins from zones 0, 1, and (NFPA) classified ethanol as a flammable liquid.
2 according to the risk level. Zones 20, 21, and 22 According to OSHA, C2H6O meets the criteria for
are only intended for areas containing combustible category 2 flammable liquid because it ignites at
chemicals in the form of dust (combustible dust). normal room temperatures, and has a flash point of
The determination of gas or dust groups along with 550 F and 1730 F boiling point (OSHA, 2022).
temperature classes is applied to each hazardous Ethanol vapor’s combination with air in the
zone by considering the characteristics such as auto- presence of ignition sources can generate fire
ignition temperature and maximum experimental and explosion. The compound’s lower and upper
gap (Choi and Byeon, 2021). explosive limits are 3.3 and 19%, respectively, by
The pharmaceutical industry produces drugs volume in air. This range includes airborne ethanol
or Active Pharmaceutical Ingredients (API) for the concentrations that can ignite and burn when there
market. The products are manufactured through is an ignition source (OSHA, 2022).
both chemical and physical means from hazardous Fire and explosion hazards exist during the
chemicals used in various operation units, which initial formation of ethanol as well as all through
exist in liquid, solid, and gaseous forms that are the product’s purification, storage, and transportation
flammable, toxic, harmful to the environment, etc. phases. Three components must be present for a fire
Consequently, the industry faces a high risk of to occur, namely fuel, oxygen (oxidizing agent), and
fire and explosion due to the handling of several heat. For ethanol fire, its vapor represents “fuel” in
hazardous chemicals (Pal, 2019). the fire triangle, oxygen is the “oxidizing agent”, and
HAC in the pharmaceutical sector is the “heat” comes from ignition sources that cause the
evaluation and classification of hazardous locations vapor to first burn (OSHA, 2022.)
according to scientific and engineering principles, PT. XY as a pharmaceutical industry in Jakarta
within facilities where chemicals are manufactured, uses ethanol in the production process of both solid
processed, or utilized. The classification is and liquid dosages. A total of 100 kg, 20 kg, and 5
performed solely to ensure the safe and proper kg ethanol are required in the solid dosage process,
 Eky Susilowati and Fatma Lestari, Hazardous Area Classification Assessment at a Pharmaceutical… 3

both for products and the cleaning process. This Furthermore, the ventilation velocity was evaluated
scenario has a potential hazard that tends to increase by direct/real measurements or using IEC/EN
fire and explosion risk, particularly during storage, 60079-10-1 guidelines. The degree of dilution was
production, and cleaning activities. Ethanol as a estimated by calculating the release characteristics
volatile solvent can form explosive atmospheres due with the following formula (1):
to its evaporation from pools created by accidental
releases. This phenomenon appears more hazardous
�� (1)
in indoor zones once there is a failure of artificial �� � ���
ventilation systems or inadequate air flow (Lauri, Wg= mass release rate of gas (kg/s); Pg= gas or
2021). vapor density at the ambient temperature (kg/m3);
At PT. XY, only ethanol is kept in the separate K= safety factor; LFL= Lower Flammable Limit
indoor flammable storage area inside 20 plastic (vol/vol).
drums (@ 200 l). The average total stock of C2H6O
in this store is 4.000 L. Ethanol is a Class IB The background concentration for indoor release
flammable liquid, hence, fire and explosion risk must was then measured and compared with background
be managed from the storage area, which cannot be criteria which were 25% of the Low Explosive Limit
isolated from loading and unloading activities. This (LEL).
management is performed to prevent the worst-case Figure 1 is used to estimate the dilution
scenario of an accidental release. Therefore, HAC is degree based on ventilation velocity and release
needed to determine area classification and identify characteristics value, while the hazardous zone is
potential improvements concerning the prevention determined with Table 1 according to dilution degree
of ignition in a hazardous area. and ventilation availability.
HAC assessment was carried out at PT. XY The extent of hazardous zones is evaluated from
for approximately 2 months from early December the characteristics and type of release (gas or vapor)
2021 to late January 2022. This referred to the IEC/ using the chart in Figure 2. Besides, the flash point
EN 60079-10-1 guidelines and involved an external analysis was conducted by an external laboratory
laboratory to test the flash point of ethanol at a 96% using the ASTM D-93 method to define ethanol’s
concentration stored and used by PT. XY. With category.
this assessment, it is expected that the company
can implement corrective actions to prevent the
RESULT
fire and explosion risk according to the established
recommendations. Ethanol with 96% concentration was stored
indoor in plastic drums at a flash point of 160C
based on testing. Also, it had a 780C boiling point
METHODS
according to the Safety Data Sheet (SDS) and was
This assessment was carried out in December categorized as a Class 1B liquid (Marando, 2021).
2021 - January 2022 using the quantitative The existing ethanol tanks found were empty and
method outlined in IEC/EN 60079-10-1 for zone not used anymore. Therefore, the potential risk
classification. This classification depends on the of flammable vapor release from leaking drums
following parameters, namely source release grade, (possibly due to being struck by a forklift) was
dilution degree, and ventilation availability classified as secondary release grade. Characteristics
The first step in evaluating hazardous areas of release from ethanol are as follows: Flammable
based on IEC/EN 60079-10-1 guidelines was to substances (Ethanol); Molecular mass (M) (46.07
determine the combustible gas/vapor release g/mol); Vapor pressure (Pv) (12.874 Kpa); Storage
scenarios, i.e., release from piping flanges, seal, temperature (Ta) (3060K (Ta)); The temperature of a
venting, etc. Afterward, the type of flammable liquid (T) (2730 K); LFL (3.3% vol.); Auto-ignition
material (vapor or gas) was confirmed to help temperature (3630 C); Volumetric evaporation rate
ascertain the appropriate calculation for the release (229E-03); Pool surface area (Ap) (20 m2).
rate. At this stage, the physical and chemical The volumetric evaporation rate was calculated
data were compiled from flammable materials to based on the following formula (2):
calculate the release rate, such as molecular mass,
vapor pressure, Low Flammable Limit (LFL), etc. 6,5 𝑢w �,�� 𝐴p 𝑃v 𝑇𝑎 m�
𝑄g = X � � (2)
10� 𝑀�,��� 𝑇 s
4 The Indonesian Journal of Occupational Safety and Health, Volume 12, Special Issue 1, February 2023: 1-11

Figure 1. Determination of Dilution Degree Assessment

Figure 2. Determination of the Estimated Distance to Hazardous Area (Extent Zone)

 Eky Susilowati and Fatma Lestari, Hazardous Area Classification Assessment at a Pharmaceutical… 5

Table 1. Hazardous Zone Determination by the Grade of Release and Ventilation Effectiveness
Ventilation Effectiveness
High Dilution Medium Dilution Low Dilution
Grade of
Release Availability of Ventilation
Good, Fair, or
Good Fair Poor Good Fair Poor
Poor
Non-
Zone 2 (Zone Zone 1 (Zone Zone 0 + Zone 0 +
Continuous hazardous Zone 0 Zone 0
0 NE)a 0 NE)a Zone 2c Zone 1
(Zone 0 NE)a
Non-
Zone 2 (Zone Zone 2 (Zone Zone 1 + Zone 1 + Zone 1 or Zone
Primary hazardous Zone 1
1 NE)a 1 NE)a Zone 2 Zone 2 0c
(Zone 1 NE)a
Non- Non-
Zone 1 and even
Secondary hazardous hazardous Zone 2 Zone 2 Zone 2 Zone 2
Zone 0d
(Zone 2 NE)a (Zone 2 NE)a
a.Zone 0 NE, 1 NE, or 2 NE indicates a theoretical zone that would be negligible extent under normal conditions.
b.Zone 2 created by a secondary grade of release may exceed the one attributable to a primary or continuous grade of release. In
this case, the greater distance should be selected.
c.Zone 1 is not needed here because small zone 0 is found in the area where the release is not controlled by ventilation, and
larger zone 2 is for when ventilation fails.
d.Zone 0 contains very weak ventilation and the grade of release is in such a way that in normal operations, an explosive gas
atmosphere keeps existing almost continuously (i.e. approaching a ‘no ventilation’ condition).
‘+’ signifies ‘surrounded by’
The availability of ventilation in a naturally ventilated enclosed space is commonly not

Figure 3. Degree of Dilution in Ethanol Storage Areas

6 The Indonesian Journal of Occupational Safety and Health, Volume 12, Special Issue 1, February 2023: 1-11

The ventilation velocity in the storage area was Figure 1 shows a release characteristic of
0.5 m/s as recommended in IEC/EN 60079-10-1 for 0.131 m3/s (based on formula (3) calculation), a
enclosed areas and based on the evaluation of the safety factor of 0.5, and 0.5 m/s ventilation velocity,
ambient condition. The release characteristics were hence the dilution degree of ethanol storage areas is
determined with formula (1). From formula (2), Qg medium as indicated in Figure 3.
i.e. volumetric evaporation rate, is equal to Wg/Pg, According to Table 1, ventilation availability
and it can be simplified to: is assumed as fair, and the grade of release is
�� secondary (the leak does not occur all the time), then
(3) the storage zone fell into category 2. Zone mapping
� ��� in storage is demonstrated in Figure 4.

Figure 4. Zone Mapping for Ethanol Storage Areas Figure 6. Zone for Ethanol Storage with Ventilated
Wall

Figure 5. Hazardous Area Distances for Ethanol Storage

 Eky Susilowati and Fatma Lestari, Hazardous Area Classification Assessment at a Pharmaceutical… 7

Figure 2 shows the extent of zone and heavy one of the factors, i.e. grade of release, can define
gas characteristics where ethanol vapor is heavier the hazardous zone, where continuous, primary,
than air, and the zone is 3 m from the release source and secondary release produces zones 0,1, and
as indicated in Figure 5. Since the drums are stored 2, respectively. This is not appropriate without
near the wall and the next room has mechanical considering ventilation effectiveness in the process
ventilation, the extent of zone 2 is up to 3 m wide (International Electrotechnical Commission, 2020).
around the pierced concrete wall as displayed in the Based on the results, the potential release
real picture presented in Figures 6 & 7. This also source comes from drums’ leakage specifically
applied to outside storage areas indicated in figure while loading and unloading ethanol using a forklift.
8. The leakage scenario is observed from one drum
containing 200 L due to the unavailable history of
release in large quantities. Furthermore, the operators
DISCUSSION
always physically inspect the ethanol drum twice
and drive the forklift carefully based on the provided
The Grade of Release Sources at Ethanol Storage procedures and license regulations. The leaks at
Areas ethanol storage tanks are classified as a secondary
Before discussing the source of release, it is grade of release sources because they only occur
necessary to know the characteristics of ethanol as occasionally. Secondary grade releases do not occur
a flammable liquid. The NFPA grouped flammable under normal conditions and for more than a few
liquids based on flash and boiling points as class I resources at the same time, only the largest value
with sub-classifications. As already mentioned in should be considered (International Electrotechnical
the results, ethanol is a class 1B flammable liquid Commission, 2020).
that has a flash point of 160C (below 22.80C) and In a case study on evaporation in a bioethanol
a boiling point of 780C (above 37.80C) (Marando, storage depot (Lauri, 2020), emission/release sources
2021). in case of failure can come from some components
The things that are considered in determining such as flanges, valves, and pumps. The potential
the classification of hazardous areas include the release source examined is the flange used in
grade of release and ventilation effectiveness. The connecting the bioethanol transfer pipe to the tanks.
release source refers to the point from which a Leakages from the flange are usually due to gasket
flammable liquid is leaked into the surrounding wear. This situation triggers a possible occurrence
environment to form an explosive atmosphere. The of an explosive mixture in the depot during normal
grade of release is divided into three classifications, operations, and the release source is classified under
namely continuous, primary, and secondary primary grade.
(Buyukkidan, Gumus and Uslu, 2021). Basically, Evaluation of the release source based on
its form includes the release rate of hazardous
chemicals existing as gases or vapors, liquids, and

Figure 7. Zone for Ethanol Storage with Mechanical

Ventilation Figure 8. Zone for Outside Ethanol Storage
8 The Indonesian Journal of Occupational Safety and Health, Volume 12, Special Issue 1, February 2023: 1-11

evaporation pools. This can be calculated based with the results of 0.131 m3/s and ventilation
on the guidelines presented in appendix B of IEC/ velocity of 0.5 m/s. Ventilation availability is
EN 60079-101. During ethanol storage, the release considered fair as there is no backup ventilation
source is evaluated according to the release rates of fan in case the main one fails to work in the storage
evaporating pools. This general scenario states that area for short periods. The final result showed
any leakage inevitably leads to the formation of a that the dilution degree was medium as indicated
pool near the source (Bozek, 2018). in Figure 3. Medium dilution is a concentration
The scenario of a possible release source with that can be controlled during the release, and in
a total loss of one drum (200 L) had a pool surface particular, atmospheres containing explosive gases
area (Ap. in m2) of 200 L/10 cm which was equal to shortly after the release is then stopped to establish a
20 m2. This was used due to the unavailable history stable zone boundary (International Electrotechnical
of catastrophic incidents resulting from container Commission, 2020).
leaks, but some leaks tend to occur from loading and Increasing the ventilation velocity causes a
unloading activities performed with a forklift in the small decrease in the pool radius (3.6%) since the
storage area. evaporation rate is much lower than the mass flow
There is a greater risk of fire due to thermal released from the control valve. The pool radius
exposure in large-volume ethanol storage tanks. trend strongly influences the biofuel evaporation
The results of the case study presented by Sjöström rate. In a case study focused on the formation of
et al. (2015) showed that an increase in the ethanol an explosive atmosphere during bioethanol storage
content caused an elevation in the thermal impact (Lauri, 2021), elevating the ventilation velocity
such that the entire surface burned in a large-scale causes an increase in the evaporation rate, but not
fire test with a fuel area of 254 m2. A small-scale high enough to modify the dilution degree (its value
fire test carried out on an area of 2 m2 conversely is medium).
indicated that the ethanol content reduced the
thermal impact on the surrounding environment. Hazardous Area Classification in Ethanol
Therefore, the thermal impact of a large pool of fires Storage
on the immediate area will pose a risk of damage to The zones in HAC are determined based
facilities, as well as increase fatal injuries and fire on the type of flammable/combustible material,
spread, making extinguishing efforts more difficult temperature, and heat pressure, as well as the leak
(Sjöström et al., 2015). size present while handling the material (Choi and
Byeon, 2021). In the IEC/EN 600-79-1 standard,
Dilution Degree in Ethanol Storage Areas
the zone type found in a hazardous area based on
An explosion can occur supposing a flammable the grade of release and ventilation effectiveness
substance (its concentration must be included within is specified in Table 1. Furthermore, the zone
its flammability limits), oxygen, and the required type determines the selection of proper equipment
activation energy which is provided by an ignition (electrical and mechanical). This will influence
source, are simultaneously present. Ethanol mists work and emergency procedures where special
with an energy of 20 J will be ignited. The flame precautions/restrictions must be taken to reduce the
propagations observed for ethanol as the minimum possibility of fire originating from ignition sources
ignition energy is 0.23 mJ (El-Zahlanieh et al., in hazardous areas (Nilsen et al., 2007).
2020). Standard electrical equipment used in hazardous
The evaporation rate helps in determining the areas includes explosion-proof containers or
dilution degree, which is a required parameter for enclosures, intrinsically safe equipment types,
identifying areas where an explosive atmosphere inter-space protection systems, and non-sparking
may occur (Lauri, 2021). The dilution degrees are maintenance tools (Setiawan, Nugroho and Zaman,
divided into three categories, namely high, medium, 2020).
and low (International Electrotechnical Commission, The cover or container of electrical equipment
2020). used in hazardous areas has a protective design
In this study, before estimating the dilution meant to prevent sparks or explosions from escaping
degree in ethanol storage, the pool surface area, and to the exterior because the lid’s density is high
volumetric evaporation rate according to formula (Setiawan, Nugroho and Zaman, 2020).
2 were calculated, alongside release characteristics
 Eky Susilowati and Fatma Lestari, Hazardous Area Classification Assessment at a Pharmaceutical… 9

Ventilation effectiveness assessment in an increase in room temperature that has the potential
ethanol storage area is based on the degree of to cause a fire outbreak. Additional engineering
dilution and ventilation availability. The dilution controls (early warning systems) are needed for
degree is pre-defined to be medium, while ventilation safe use by detecting the presence of ethanol vapor
availability in the storage tanks is considered fair released into the air through the installation of flame/
because the Air Handling Unit (AHU) can be turned LEL gas detectors in the storage area. This is to
off for a short period during repair or preventive confirm whether the LEL level is within the standard
maintenance. After determining the grade of release acceptable limits.
and ventilation effectiveness, the final result showed The same method is also used in zones with
that the storage area is hazardous with zone 2 and scenarios of leakages from pumps handling liquid
an extent of 3 m from the release source. Zone pentane during the refinery processes under normal
2 can be described as an area with an explosive operation. This outflow from the pump seal creates
gas atmosphere that occurs for a short time in a flammable vapor mixture in the atmosphere
abnormal operations (International Electrotechnical containing the leaks, which collect to form a pool
Commission, 2020). The extent of zone is based on within the containment dyke. The flammable vapor
release characteristics and type of release. mixture is determined by the ambient air temperature
Once the NFPA approach is used, the ethanol and vapor pressure of the liquid pentane. Pentane is
storage process size, pressure, and flow rate will fall a flammable liquid with a vapor pressure of 75 kPA
into the small/low category, hence, Figure 5.10.1 (e) at 200C and a molecular weight of 72 kg/mol. To
of the NFPA 497 standard applies. The zone based calculate the release characteristic value of pentane
on NFPA 497 standard is the same as the Division for determining the zone and its extent, the data
or zone 2 in the IEC approach but the extent is more on ventilation speed, safety factor, and LFL with a
than twice, i.e. 7.62 m, of the value obtained with final volume of 0.4 m3/s are needed. This is based
the IEC approach (Goyette, 2011). on a safety factor value of 0.5, 1.5% LFL, and 0.25
The equipment group and temperature class m/s ventilation/wind speed. Therefore, the pentane
for this zone 2 in the ethanol storage area are release area is categorized as zone 2 with medium
called Zone 2 IIA T2. One of the selections of this dilution. Zone 2 has an extent of approximately 6
equipment is based on the temperature class of m for heavy gas release according to the standards
the flammable liquids regulated by the IEC. When (Bozek, 2018).
selecting suitable equipment, the temperature A case study for an area with tanks containing
class must be lower than the minimum ignition of Liquefied Petroleum Gas (LPG) also used the same
explosive mixtures in hazardous areas to reduce method, resulting in the area being categorized as
fire and explosion risk. The temperature classes zone 2. This was based on the secondary release
based on IEC/EN 60079 standards were 6, namely of LPG from the tanks’ bottom, and the release
T1 (4500C), T2 (3000C), T3 (2000C), T4 (1350C), characteristics were calculated under sonic and
T5 (10000C), and T6 (850C) (Ahirwal, Singh and subsonic conditions with values of 4.947 and 3.927
Vishwakarma, 2015). m3/s, respectively, at a 1.08 m radius (Buyukkidan,
Electrical equipment which are the ignition Gumus and Uslu, 2021).
sources in the ethanol storage area must meet the In addition to the method based on IEC/EN
level of protection (explosion-proof) according to 60079-10-1, a risk assessment method involving
zone 2 standards including lighting, AHU motors, a matrix is also used to determine the explosive
and fire alarm system installation. A certificate of atmosphere severity. A total score of 12 was obtained
conformity for Atmosphere Explosion (ATEX) from from this assessment by multiplying the probability
this equipment should be checked. Besides, the of occurrence in a week (3P) and the consequences
ventilation fan has no alarm to indicate failure as that could lead to serious injury (4P). Serious threats
well as no backup fan in case the main one stops and devastating effects were clearly fictionalized by
working. Therefore, the storage area is categorized explosion scenarios of the LPG tanks with ALOHA
as zone 2 and the installation of an alarm is software, divided into several modeling scenarios
recommended. Foam fire extinguishers (Aqueous (Buyukkidan, Gumus and Uslu, 2021).
Film Forming/AFF) weighing 25 kg were placed In another case study based on the NFPA 497
outside the ethanol storage area and the inside was standard with a leakage scenario of flammable
equipped with heat detectors for detecting a drastic liquids located indoor at the floor level. This
10 The Indonesian Journal of Occupational Safety and Health, Volume 12, Special Issue 1, February 2023: 1-11

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granted permission for the study location, as well as
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the Department of Occupational Health and Safety,
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Faculty of Public Health, Universitas Indonesia, for
Lauri, R. (2021) ‘Assessment of Atmospheric
providing support during the article preparation.
Parameters Influence on Dilution Degree : A
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OSHA (2022) Section IV (previously Section III of
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