11°50′53″N 75°25′44″E / 11.848°N 75.429°E
  Chala  Thiruvananthapuram Location of Chala in Kerala | |
| Date | 27 August 2012 |
|---|---|
| Venue | Indian National Highway 17 (now NH 66) |
| Location | Chala, Kannur, Kannur district, Kerala, India |
| Type | LPG road tanker boiling liquid expanding vapour explosion (BLEVE) |
| Cause | Collision with road divider |
| Deaths | 20 |
| Non-fatal injuries | 21 |
The Chala LPG tanker disaster was a road transport accident that occurred on August 27, 2012, on Indian National Highway 17 (now NH 66) at Chala in the Kannur District of India's Kerala State. The accident occurred when an Indian Oil Corporation Limited (IOCL) LPG road tanker hit a road lane divider, overturned and exploded, starting several building fires between 9:30 p.m. and 11 p.m. The accident killed 20 people.[1]
Background
Government-owned Indian Oil Corporation Limited (IOCL) is an integrated energy major with presence in all the streams of oil, gas and petrochemicals. Among its activities, IOCL transports liquefied petroleum gas (LPG) produced in its refineries to cylinder filling facilities through terrestrial pipelines, railway tank trains and road tankers. IOCL owned the cylinder bottling plant in Chelari, Kozhikode district, Kerala, which receives LPG by road tankers from the Mangalore LPG Import Facility (MLIF), also owned by IOCL and situated 264 km away in Karnataka.
LPG Bullet-shaped tanks mounted on trailer tankers normally have a capacity in excess of 17-tonnes in three compartments.[1]
National Highways in India are constructed and maintained by the National Highway Authority of India (NHAI) and the individual states' public works departments (in this case the Kerala Public Works Department).
Accident
On August 12, 2012 the LPG road tanker involved in the accident was loaded with 17.82 tonnes of LPG in Mangalore, Karnataka, from where it left at 8:18 a.m.[2] It was directed to an Indane (an IOCL subsidiary) LPG bottling plant in Chelari, Kozhikode district, Kerala. In this state LPG tankers are not allowed to travel in public roads between 6:00 a.m. and 6:00 p.m., so the tanker had to stop and wait at the state border for several hours. Around 10:30 p.m., while crossing the town of Chala, between Kannur and Thalasseri, the driver tried to overtake a vehicle and, in so doing, hit a concrete road divider near the Bhagavati temple bus stop.[3]
The lane division was installed to segregate traffic in opposite directions. The concrete divider started at the temple bus stop –where the slope from the adjacent hill levelled off– and extended 200 metres up to the next junction. The divider was constructed by fixing 50 cm-high concrete blocks along the centre line. The blocks, originally painted in white and black stripes, were blackened with vehicle exhausts.[4] There was no sign warning of the obstruction at the beginning of the division. Several traffic accidents had been reported at this spot in the year prior to the accident, with one of them involving an empty LPG tanker collision with the divider and occurring just one week before the disaster.[2] There were a few one- and two-storied commercial buildings on the north side of the highway and several houses on both sides. The nearest house was within 15 m of the highway.[3]
Upon contact, the tractor unit detached from the tank trailer. The valve manifold of the tank broke and LPG started leaking.[2][5] Where the accident occurred, the terrain slopes down by 1 to 3 metres below the road level on both sides of the highway. The leaked liquid LPG and its heavy vapours descended there and flowed for 170 metres through an irrigation water canal running north to south and crossing the highway roughly at the spot where the accident occurred.
The driver was able to exit the cabin and alert nearby residences before the fire started. Residents called the Kerala State Electricity Board, which immediately isolated the power supply grid. Most of the persons living around the accident spot evacuated their homes, moved away for some distance and stood on the street along the water canal.[1][5]
Ignition occurred between around 20 minutes after the tanker overturned. The source of the ignition is unclear.[5] There was a flash fire in the gas spread around the overturned tanker, in the water canal and in the low-lying area on the south side. The gas settled in the canal is said to have burnt for 1 to 2 minutes. Persons who had evacuated their houses but stood on the streets on the south and north side of the highway suffered burn injuries. Once the flash fire subsided, a jet fire remained at the leaking area of the overturned bullet tank. During this period the neighborhood had attempted search and rescue in fire-impacted houses.[3]
Ten minutes after the onset of the fire, the LPG bullet tank, heated and weakened by the jet fire, ruptured and a severe boiling-liquid expanding-vapour explosion (BLEVE) ensued. A huge fireball formed and half of the burning tank rocketed upwards, flew over the coconut groves and fell almost 400 metres away.[5] The fireball diameter is estimated to have been around 150 metres eith its duration in the order of 9–11 seconds.[3]
Damage and casualties
Fire engines of Kerala Fire and Rescue Services services approached the accident, with some of them arriving before the BLEVE onset. Five fire engines from Kannur (7 km away) and Thalassery (15 km away) fire stations attended the incident.
Victims suffered burns from the first flash fire and the BLEVE. These were the people who evacuated their houses but stood along the highway when ignition occurred. However, there was no injury due to consequent building fires. Twenty people died due to burn injuries in various hospitals in a period between 24 hours to 30 days from the time of the incident. Another 21 received treatment for burns.[1] The fire damaged 20 houses and 23 shops,[6] although reports on this subject differ.[1][3] Seven houses suffered severe fire and explosion damage necessitating demolition. Eleven vehicles were gutted in the fire.[7]
Aftermath
The tanker driver was arrested by the police at a later date.[2]
The tragedy caused local uproar and protest against government officials who visited the accident site. Kerala Chief Minister Oommen Chandy, his ministerial colleagues and the leader of the opposition V.S. Achuthanandan visited the accident spot, the hospitalized victims and the houses of those who died. Achuthanandan demanded that a murder case be filed against IOCL.[6][7]
During his visit, Chandy ordered the removal of the road divider involved. This action was later criticized as destruction of evidence.
Several voluntary social organizations worked in the following months in the area to help with restoration of the houses and the rehabilitation of traumatized families.
Protests and blockade of LPG tankers occurred in several parts of the district for a few months. People demanded that LPG transport on roads in the state be stopped and manhandled tanker drivers. In response, the Southern Region Bulk LPG Transport Owners’ Association called a strike in September 2012.[8]
IOCL paid a compensation of ₹1.3 million (ca. US$25,000) for each deceased.[9]
Investigation
Enquiries conducted by the District Collector and State Government are accessible to the public.
Twenty-two people gave statements in a magisterial enquiry conducted by Kannur District Collector Rathan Kelkar. The owner of a shop near the accident site stated in the enquiry that there was no reflector on the road divider and that the divider was not visible at night due to poor lighting. However, in the same enquiry a Kerala Public Works Department (PWD) official stated that the divider blocks were painted in black and white reflector stripes and a warning sign was present.[4]
The Oil Industry Safety Directorate (OISD), under the Ministry of Petroleum and Natural Gas, published a short report in 2013, which states that the driver's license to carry dangerous goods was expired and the tanker was travelling without a back-up driver, although one was present at the start of the journey. The report concludes that the root causes of the accident were: Issues associated with the stretch of road where the crash occurred, including the lack of traffic signs and in particular of one warning of the obstruction caused by the divider; driver fatigue; and absence of a back-up driver. It further recommended that authorities should ensure strict enforcement of the provisions of the Motor Vehicles Act Motor Vehicles requiring the use of back-up drivers for certain type of journeys and services. It also recommended design improvements to LPG road tankers, including mechanical protection of the valve manifold, and fitting of an excess flow check valve inside the tank, to make it so that external damage on the valve manifold would not result in catastrophic loss of containment.[2]
IOCL announced that their LPG tankers would indeed be fitted with an excess flow check valve inside the tank and also committed to enforce the requirement for two drivers manning their LPG road tankers.[9]
The OISD findings are consistent with declarations released by the authorities and on public media. In press conferences after the accident, Chief Minister Chandy stated that improper design of the concrete lane divider was a significant cause of the disaster. Asianet News reported the fatigue of the lone driver and absence of illumination as potential causes.[10] M. Ponnambalam, president of the Southern Region Bulk LPG Transport Owners’ Association (SRBLPGTOA) said that the accident happened due to poor road conditions and that "driving through Kannur’s bad roads is a nightmare."[8]
Later LPG tanker overturning
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In the afternoon of May 6, 2021, an LPG road tanker operated by IOCL overturned 200 metres away from the site of the 2012 accident.[11] The tanker capsized whilst maneuvering in a 90-degree turn.[12] This time the leak was small, in the vapour phase, and did not ignite. Residences were evacuated in a 500 metre radius, and the highway was closed for 12 hours until a IOCL emergency recovery tanker removed the inventory from the overturned vehicle.
References
- 1 2 3 4 5 Kumar, Pramod (2013). "Fire Disaster Following LPG Tanker Explosion at Chala in Kannur (Kerala, India): August 27, 2012". Burns. 39 (7): 1479–1487. doi:10.1016/j.burns.2013.04.004. PMID 23639222.
- 1 2 3 4 5 Roy, U.S.; Agrawal, Rakesh. "LPG Tank Truck Road Accident and Subsequent BLEVE". Oil Industry Safety Directorate. Archived from the original on 2020-09-21. Retrieved 2023-11-09.
- 1 2 3 4 5 Bariha, Nilambar; Mishra, Indra Mani; Srivastava, Vimal Chandra (2016-01-25). "Fire and Explosion Hazard Analysis Furing Surface Transport of Liquefied Petroleum Gas (LPG): A Case Study of LPG Truck Tanker Accident in Kannur, Kerala, India". Journal of Loss Prevention in the Process Industries. 40: 449‒460. doi:10.1016/j.jlp.2016.01.020.
- 1 2 Times News Network (2012-09-29). "Locals Blame Divider for Chala Mishap". The Times of India. Archived from the original on 2023-06-27. Retrieved 2021-04-15.
- 1 2 3 4 Bariha, Nilambar; Mishra, Indra Mani; Srivastava, Vimal Chandra (2014). "Analysis of Fire and Explosion Hazards During Surface Transport of Liquefied Petroleum Gas" (PDF). Institution of Chemical Engineers. Symposium Series No. 159: Hazards 24. Archived (PDF) from the original on 2023-06-27. Retrieved 2023-11-09.
- 1 2 "Tanker Tragedy at Chala: Death Toll Rises to 7". The Hindu. 2012-08-30. Archived from the original on 2013-12-05. Retrieved 2023-11-09.
- 1 2 "LPG Tanker Explosion Toll Touches 18 in Kerela". Zee News. 2012-09-02. Archived from the original on 2023-06-28. Retrieved 2023-11-09.
- 1 2 Simhan, T.E. Raja (2012-09-20). "LPG Tanker Operators Threaten to Stop Services in South". The Hindu. Archived from the original on 2023-06-27. Retrieved 2023-11-09.
- 1 2 "LPG Tanker Blast Still Haunts Chala Survivors". The Times of India. 2013-08-27. Archived from the original on 2023-06-28. Retrieved 2023-11-09.
- ↑ Asianet News (2013-08-23). Chala LPG Tanker Accident (Television production) (in Malayalam). Retrieved 2023-11-09.
- ↑ Rajeev, K.R. (2021-05-06). "Kerala: Gas Leak Creates Panic After LPG Tanker Lorry Overturns in Kannur". The Times of India. Archived from the original on 2023-06-27. Retrieved 2023-11-09.
- ↑ "Speeding, Poor Judgment Capsized LPG Tanker at Chala, Reveal CCTV Visuals". Onmanorama. 2021-10-05. Archived from the original on 2023-06-27. Retrieved 2023-11-09.