GRD Journals- Global Research and Development Journal for Engineering | Volume 5 | Issue 8 | July 2020 ISSN- 2455-5703
Evaluation of Hazard and Minimization of Risk of Nitroglycerin in Pharma Industry using ALOHA & Event Tree Analysis Md. Asif Qureshi Student Department of Industrial Safety Engineering SKSITS, Indore
Nisha Kushwaha Assistant Professor Department of Industrial Safety Engineering SKSITS, Indore
Abstract As we all know chemicals are highly hazardous and toxic in nature. They are hazardous till the stage of manufacturing to the stage of storage. This is a study which has been carried out in a pharma industry where the workers are exposed to Explosive and hazardous chemicals such as Nitroglycerin, Chlorine dioxide, Hydrogen peroxide, Methanol and other like these. In this research physical and chemical properties of chosen chemicals are studied. In the second step we have done checklist analysis where the needed data is collected which is going to be used for further steps.in the next step we have to select a highly hazardous or toxic chemical, Toxicity Calculation and hazardous risk is used to rank the chemicals based on the data gathered from checklist. After these selections are made for highly hazardous or toxic chemical, the next step is to find out what are the consequences and risk we are going to face if there is an accident or release of these toxic chemicals in environment. For this, Event Tree Analysis (ETA) is used in next step. In the next step we have to calculate the risk from ETA and find that how it is dispersed into atmosphere and till how much distance it’s going to affect. In the next step we are to calculate human health and safety loss, using the distance found out by software and compensation amount collected from laws. In the final step we will make the precautionary & preventive measures to avoid the toxicity dispersion of chemicals in atmosphere with emergency preparedness in case of chemical release by any means. Keywords- Nitroglycerin, Event Tree Analysis, ALOHA, Fire Hazard Related to Chemical
I. INTRODUCTION TO HAZARDOUS MATERIAL A. Nitroglycerin Neat Nitroglycerin is diluted in Lactose monohydrate, Propylene glycol, Alcohol and other inert medium e.g. Solvated adhesive of various grades as per the customer’s requirements UP state FDA granted license to manufacture following variants of Nitroglycerin drug substances / bulk drugs. – 15%, 17.5%, 17.7%, 18%, 19%, 20% ,21% and 22% w/w Nitroglycerin in Solvated adhesive – 10% w /w Nitroglycerin in Lactose / Propylene glycol / Ethyl alcohol – 5% w /w Nitroglycerin in Lactose / Propylene glycol / Ethyl alcohol – 2% w /w Nitroglycerin in Lactose / Propylene glycol / Ethyl alcohol B. Hand Sanitizers Hand sanitizer kills 99.6 % germs in 30 seconds. Purified water, generated in state-of-the-art water purification plant, used in the formulation In house quality control of all inputs as per the hand sanitizer Microbiological laboratory equipped with Double door autoclave, incubators (Automatic temperature control), very smooth work station and pass box. C. – – – – –
Compositions Isopropyl Alcohol I.P.: 75% v/v Glycerol I.P.: 1.45% v/v Hydrogen Peroxide Solution I.P. (eq. to H2O2): 0.125% v/v Purified Water: QS Ethyl Alcohol I.P.: 80% v/v Glycerol I.P. 1.45% v/v Hydrogen Peroxide Solution I.P. (eq. to H2O2): 0.125% v/v Purified Water: QS Isopropyl Alcohol I.P.: 70% v/v Chlorhexidine Gluconate Solution I.P.:0.5% w/v (eq. to Chlorhexidine Gluconate) Purified Water I.P.: QS Ethyl Alcohol I.P.: 70% v/v Chlorhexidine Gluconate Solution I.P.: 0.5% w/v (eq. to Chlorhexidine Gluconate) Purified Water I.P.: QS
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Evaluation of Hazard and Minimization of Risk of Nitroglycerin in Pharma Industry using ALOHA & Event Tree Analysis (GRDJE/ Volume 5 / Issue 8 / 004)
II. LITERATURE REVIEW H Stessel et al. Stated that their data indicate that ascorbate deficiency results in vascular tolerance to GTN via proteasomal degradation of ALDH2. The results support the view that impaired ALDH2-catalysed metabolism of GTN contributes significantly to the development of vascular nitrate tolerance and reveal a hitherto unrecognized protective effect of ascorbate in the vasculature.[1] Juan A. Vílchez (2012) et al. explained that each sequence will lead to a final accident scenario, the severity of which will range between “no outcome” (no consequences or negligible consequences for people and property) and a “major accident”. In this paper, the authors used the EC labeling and CPR 18Efor finding the exact probabilities of accidental events occurring. The author concluded that which is more hazardous and what needs immediate attention by probability and event trees [2-3-4]. N.S.Arunraj (2009) et al. stated that the consequences analysis is important part in risk calculation. The authors used simple methods to evaluate the consequences analysis especially the losses such as production, human health and safety, environmental and assets. The proposed methods are than applied to case study to compare with the existing methods [4].
III. METHODOLOGY
IV. APPROACH OF SAFETY INFORMATION SYSTEM In this chapter, the process of empirical data collection for the study will be presented and discussed. I will discuss: what sort of material was collected, which methods of data collection were chosen and why, different challenges I faced as well as general experiences and learning in the process. Finally, thoughts will be given regarding the quality of the study, including limitations of data collected and ethical considerations.
V. THEORITICAL FRAMEWORK
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Evaluation of Hazard and Minimization of Risk of Nitroglycerin in Pharma Industry using ALOHA & Event Tree Analysis (GRDJE/ Volume 5 / Issue 8 / 004)
VI. HAZARD IDENTIFICATION
VII.
TOXICITY SUMMARY
The oral LD50 of nitroglycerin in rats is 105 mg/kg and the intravenous form in rats is 23.2 mg/kg. An overdose of nitroglycerin can lead to a variety of hemodynamic effects. General effects may include vertigo, fever, flushed skin, and diaphoresis. Cardiorespiratory symptoms may include syncope, dyspnea, decreased heart rate, or palpitations. Neurologic manifestations can include paralysis, seizures, coma, and death. There are no known antidotes to an overdose of nitroglycerin, and it is not known whether its metabolites can be removed from the circulation. If hypotension occurs due to an overdose with nitroglycerin, elevate the lower limbs and administer an intravenous infusion of normal saline or other fluids if necessary to maintain central fluid volume.
VIII. FIRE HAZARDS Will be easily ignited by heat, sparks or flames (Highly Flamable). Vapors may form explosive mixtures with air. Vapors may travel to source of ignition and flash back. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapor explosion hazard indoors, outdoors or in sewers. Those substances designated with a (P) may polymerize explosively when heated or involved in a fire. Runoff to sewer may create fire or explosion hazard. Containers may explode when heated. Many liquids are lighter than water. Many reactions may cause fire or explosion. Gives off irritating or toxic fumes (or gases) in a fire. Risk of fire and explosion. A. Explosive Limits and Potential Severe explosion risk, highly sensitive to heat and shock, Explosion point 256 °C Intense ultraviolet radiation will explode a sample at 100 °C. The sensitivity to shock is greatly diminished by absorption onto porous solids. Undiluted nitroglycerin should be handled cautiously since it is a powerful explosive that can be exploded by percussion or excessive heat. Nitroglycerin is diluted with lactose, dextrose, alcohol, propylene glycol, or another inert excipient to permit safe handling. All rights reserved by www.grdjournals.com
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Evaluation of Hazard and Minimization of Risk of Nitroglycerin in Pharma Industry using ALOHA & Event Tree Analysis (GRDJE/ Volume 5 / Issue 8 / 004)
IX. STORAGE DETAILS Store only if stabilized. Store in an area without drain or sewer access. Fireproof. Well closed. Separated from food and feedstuffs. Wall capacity: 12 x 10 x 2.5 M A. Physical and Chemical Properties of C3H5N3O9 Molecular Weight: 227.10 g/mol Ambient Boiling Point: 121.7° F Freezing Point: 35.6° F B. Following Physical Data Applies to Pure Nitroglycerin Nitroglycerin injections are practically colorless and stable in their intact containers. The solutions are not explosive. Storage should be at room temperature; the containers should be protected from freezing. Exposure to light, even high intensity light, does not adversely affect nitroglycerin stability. Store at room temp not above 25 °C (77 °F). Do not refrigerate. C. Exposure Control and Personal Protection Short Term Exposure Limit -0.1 mg/m³ and ST 0.1 mg/m3 [skin] Immediately Dangerous to Life or Health Nitroglycerin is immediately dangerous to life when exposed before 75 mg/m3 D. Threshold Limit Values Excursion Limit Recommendation: Excursions in worker exposure levels may exceed 3 times the TLV-TWA for no more than a total of 30 minutes during a work day, and under no circumstances should they exceed 5 times the TLV-TWA, provided that the TLV-TWA is not exceeded. The time limit for threshold is 8 hr., Weighted Avg (TWA): 0.05 ppm for skin. E. Effects of Long-Term Exposure Repeated or prolonged contact with skin may cause dermatitis. Repeated exposure leads to marked tolerance and short absence from exposure may lead to sudden death.
X. MODELLING OF TOXIC CHEMICAL DISPERSION The event tree analysis shows that the final consequence is definitely toxic release into atmosphere. Hence, we have to calculate how it is dispersed into atmosphere. It will show how much distance covered by the toxic vapor along with concentration. Mostly the chemical vapors are diluted in air according to the wind profile, so the concentration of chemical reduced when going further distance. To calculate the atmospheric dispersion, we have two methods one is by using Software simulation and other is by using empirical formula. For both, we need the following data to do calculation and simulation, which are chemical data such as TLV, IDLH, density, temperature etc., atmospheric data such as wind speed, direction, stability etc. and storage data such as vessel size, capacity, etc. After gathered all data, formulation of worst-case scenario is done.
XI. MAIN CAUSES OF FAILURE OF TANKS The failure of tanks occurred as rupture of vessel by various reasons which are listed below, Corrosion (Stress corrosion). – Relief valve failure (Increased pressure). – Resin failure. – Static discharge explosion. – Sabotage Here, the main reason for the failure considered here both relief valve and corrosion. Because the corrosion alone doesn’t cause failure because of the nature of FRP tank is corrosion resistant but due to the corrosive nature of chemical (C3H5N3O9) mainly Stress corrosion Cracking may affect the FRP tank when it undergone ageing. If the relief valve doesn’t work properly, it may create increased pressure inside the tank which results in stress cause the cracks in already corroded area.
XII.
FORMULATION OF WORST-CASE SCENARIO
According to the wind speed, stability class for the above condition is E and F respectively. The temperature and relative humidity are 320 C & 57% and 240 C & 57% during the day and night time respectively. These atmospheric conditions mostly happened during the months of June and July. The leak type selected is hole of 5cm at lowest point of vessel because it will release more chemical outside.
XIII. SOFTWARE MODELLING OF ATMOSPHERIC DISPERSION It is one of the simplest and quick ways to identify the chemical dispersion into atmosphere and assess the threat zones. There are various software’s available such as DNV SAFETI, DNV PHAST, CHARM, CFD, ALOHA etc. In which the ALOHA is freely
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Evaluation of Hazard and Minimization of Risk of Nitroglycerin in Pharma Industry using ALOHA & Event Tree Analysis (GRDJE/ Volume 5 / Issue 8 / 004)
provided by US EPA, where other are available with cost. So, this project used ALOHA for the modeling simulation of toxic chemical Nitroglycerin (C3H5N3O9) dispersion into atmosphere.
XIV. QUALITATIVE METHOD AND RESEARCH STRATEGY To use a method, means to follow a certain direction towards a goal. It is about what measures one chooses to apply to collect information about the reality, how to analyze it, and what the collected data tells us about different conditions and processes. In research, it is common to distinguish between qualitative and quantitative research strategy. A quantitative strategy is based on numerical data collection, requiring usually large number of informants so that descriptions of the reality can be displayed and analyzed through tables and numbers. A qualitative strategy on the other hand, relies on the proximity and collection of data from a relatively a smaller number of informants where text, sound and/or picture material is interpreted by the researcher. Worst case data day time night time Atmospheric data Wind speed 3.5 m/s 4.5 m/s Wind direction NE NE Air temperature 320C 240C Stability Class E F Relative humidity 57% 61% Source strength Leak type Hole Hole Tank volume 150 m3 150 m3 Internal temperature 18.30C 18.30C Chemical mass in tank 80% 80% Hole diameter 50 mm 50 mm Hole at a height in tank 10% 10% Ground type Concrete Concrete Equivalent to Ambient Equivalent to Ambient Ground temperature temperature temperature
XV.
FLOW CHART OF ALOHA SOFTWARE
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Evaluation of Hazard and Minimization of Risk of Nitroglycerin in Pharma Industry using ALOHA & Event Tree Analysis (GRDJE/ Volume 5 / Issue 8 / 004)
XVI. RESULTS OF ALOHA SIMULATION The result from ALOHA showed that the release duration is 1 hour and then release rate of chemical is estimated around 12 kgs/min. The ALOHA result showed that the results for all three-threat zone, the dispersion is over (1 miles) which are shown in the below figure no: 10 & 11 and truncated to 1 miles in graphical representation. The above result is also same for during night time release.
Fig. 1: Release of Nitroglycerin from the storage tank during day time
Fig. 2: Release of Nitroglycerin from the storage tank during night time
Results of ALOHA Simulation with alternate data: Nitroglycerin TLV = 0.05 ppm IDLH = 4.645 mg/m3 Wind speed Wind direction Cloud cover Air temperature Stability Class Relative humidity Leak type Tank volume Internal temperature Chemical mass in tank Hole diameter Hole at a height in tank Ground type Ground temperature
Table 1: Data of Release Scenario 1: Release of Nitroglycerin from the storage tank during day time Atmospheric Data 3.5 m/s NE 3 320C E 57% Source strength Hole 150 m3 18.30C 80% 50 mm 10% Concrete Equivalent temp to ambient
Scenario 2: Release of Nitroglycerin from the storage tank during night time 4.5 m/s NE 3 240C F 61% Hole 150 m3 18.30C 80% 50 mm 10% Concrete Equivalent temp to ambient
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Evaluation of Hazard and Minimization of Risk of Nitroglycerin in Pharma Industry using ALOHA & Event Tree Analysis (GRDJE/ Volume 5 / Issue 8 / 004)
Table 2: Zone of hazard 12.02 kgs/min
Release rate 12.02 kgs/min For toxic <0.29 KM - (75 mg/(cu m) = Red < .32 KM - (75 mg/(cu m) = Default LOC-3) Default LOC-3) Orange < 1.22 KM - (5 mg/(cu m) = Default LOC-2) < 1.36 KM - (5 mg/(cu m) = Default LOC-2) < 1.77 KM - (2.5 mg/(cu m) = < 1.93 KM - (2.5 mg/(cu m) = Yellow Default LOC-1) Default LOC-1)
1) Possible Death Effects: number of people inside the damage radius to whom deaths could be induced. This radius corresponds to the LOC3/ERPG-3 (Emergency Response Planning Guidelines) concentrations for toxic release. 2) Possible Injuries: Number of people inside the damage radius to whom injuries could be induced. This radius corresponds to the LOC2/ERPG-2 concentration for toxic release. 3) Possible Annoyance: Number of people inside the damage radius that slight injuries, annoyance or other slight reversible effect could be induced. This corresponds to the LOC1/ERPG-1 concentration for toxic release.
Fig. 3: Damage radii of chemical dispersion
XVII. ACCIDENTAL RELEASE MEASURES A. Isolation and Evacuation Isolate spill or leak area immediately for at least 500 meters (1/3 mile) in all directions. LARGE SPILL: Consider initial evacuation for 800 meters (1/2 mile) in all directions. FIRE: If rail car or trailer is involved in a fire, isolate for 1600 meters (1 mile) in all directions; also, initiate evacuation including emergency responders for 1600 meters (1 mile) in all directions. B. Spillage Disposal Evacuate danger area! Consult an expert! Personal protection: complete protective clothing including self-contained breathing apparatus. Remove all ignition sources. Do not wash away into sewer. Do not let this chemical enter the environment. Collect leaking and spilled liquid in sealable containers as far as possible. Absorb remaining liquid in sand or inert absorbent. Then store and dispose of according to local regulations. C. Cleanup Methods Solvent used to remove nitroglycerin from nitration plant effluent is dinitro toluene. It is used to clean up nitroglycerin.
XVIII. PREVENTIVE MEASURES The scientific literature for the use of contact lenses in industry is conflicting. The benefit or detrimental effects of wearing contact lenses depend not only upon the substance, but also on factors including the form of the substance, characteristics and duration of the exposure, the uses of other eye protection equipment, and the hygiene of the lenses. However, there may be individual
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Evaluation of Hazard and Minimization of Risk of Nitroglycerin in Pharma Industry using ALOHA & Event Tree Analysis (GRDJE/ Volume 5 / Issue 8 / 004)
substances whose irritating or corrosive properties are such that the wearing of contact lenses would be harmful to the eye. In those specific cases, contact lenses should not be worn. In any event, the usual eye protection equipment should be worn even when contact lenses are in place. Contaminated protective clothing should be segregated in such a manner so that there is no direct personal contact by personnel who handle, dispose, or clean the clothing. Quality assurance to ascertain the completeness of the cleaning procedures should be implemented before the decontaminated protective clothing is returned for reuse by the workers. Contaminated clothing should not be taken home at end of shift but should remain at employee's place of work for cleaning.
REFERENCES [1] [2] [3] [4]
Wölkart G, Beretta M, Wenzl MV, et al. Tolerance to nitroglycerin through proteasomal down-regulation of aldehyde dehydrogenase-2 in a genetic mouse model of ascorbate deficiency. British Journal of Pharmacology. 2013 Apr;168(8):1868-1877. DOI: 10.1111/bph.12081. Fengying Li, Jun Bia, Lei Huanga, Changsheng Qua, JieYangc, QuanminBua, “Mapping human vulnerability to chemical accidents in the vicinity of chemical industry parks”, Journal of Hazardous Materials 179 (2010) 500– 506. Angela Summers, William Vogtmann, Steven Smolen,”Improving PHA/LOPA by consistent consequence severity estimation”, Journal of Loss i. Prevention in the Process Industries 24 (2011) 879-885. N.S. Arunraj, J. Maiti, “A methodology for overall consequence modeling in chemical industry”, Journal of Hazardous Materials 169 (2009) 556–574.
Website References [5] [6] [7] [8]
www.belindia.net www.webwiser.nlm.nih.gov www.cameochemicals.noaa.gov www.ilo.org
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