Since the fiery explosion at the warehouse in Tianjin on 12 August graphic images have been flashed across the world. The fire and subsequent blasts which destroyed scores of lives and property, and tossing a toxic mix of dangerous chemicals into the air, has also raised multiple questions: How did it happen? Why did it happen? Who is responsible? What chemicals were involved? How much chemicals did the warehouse have to cause the kind of damage which could be seen from outer space?
While the incident has placed the storage of chemicals in China under close scrutiny, it is a wake-up call for companies involved in chemical storage. What happened in Tianjin could well occur elsewhere in Asia if companies fail to adhere to stringent standards established for chemical storage. After all Asia is the centre of the chemical trade, accounting for half the global chemical sales. With population expansion, increasing industrialisation and urbanisation, that percentage can only increase.
What measures should operators take to ensure that chemicals are properly stored to prevent a similar incident from happening? It is a huge subject, which will receive a great deal of attention in the coming days and months, but here is a brief take of this vital subject.
Chemicals come under the broad category of dangerous goods as many of the chemicals used have dangerous properties. They may be toxic, flammable and/or explosive. They may be carcinogens or have unknown physiological effects. Unless proper care is taken in handling chemicals, they present potential hazard to people and property.
Given the risks, strict regulations covering every link in the chain have been put in place, from the classification of chemicals to warehouse design to requirements for safe storage and transportation. For anyone involved in this business, a sound knowledge of the substance and spirit of the regulations is essential.
What are some of the things we need to bear in mind in chemical storage?
Proper product segregation is vital. Classes of incompatible chemicals should be segregated from each other during storage, according to hazard class. When certain hazardous chemicals are stored or mixed together, violent reactions can occur. There is also a domino effect when a fire occurs. Chemical compatibility and segregation guides are available for easy reference.
The racking systems used must be equal to the task. They must be robust, able to withstand the anticipated maximum loading. It should incorporate in-rack fire sprinkler system to help douse flames and control the spread of fire, limiting the damage. The racks should be inspected at appropriate intervals, as any damage can compromise the system.
Where chemicals are intended to be stacked on top of one another without the use of racking then a safe maximum stack height must be determined, having taken account of the load bearing capability of the packaging.
As chemicals encompass a wide range, there should be clear labels to indicate which category the chemicals come under. Under the United Nations classification system for dangerous goods, there are nine classes according to the type of danger materials or items present for quick recognition.
For the benefit of employees as well as emergency response teams, it is also important to provide visible information about the properties of the chemicals.
Explosion proof material handling equipment
Material handling equipment used within the warehouse must be explosion proof as the gases, vapours and mists which escape during storage can provide the necessary conditions for explosions to occur. There is a broad range of EE rated equipment to meet industry needs, including forklifts, pallet trucks, drum handling equipment, lever hoists and lifting tables.
Safety and Security
The warehouse should be properly equipped to handle fires caused by flammable liquid, flammable solid, electrical equipment, etc. There must be appropriate emergency response and first aid equipment readily available, and personnel trained in the use of such equipment to deal with the different accident scenarios.
At all times, equipment such as fire extinguishers, first-aid boxes, emergency showers/eye washes must be operationally ready. They should be inspected and tested at suitable intervals.
In addition, a safety audit procedure should be implemented to systematically identify and rectify weaknesses in the management system and practices of handling hazardous chemicals on a regular basis.
As part of the safety precaution, a well-developed security system has to be installed to prevent unauthorised entry.
Track and trace
Companies should keep track of the movement of the chemicals to ensure inventory accuracy as well as meet regulatory and compliance requirements. Tools are available to help manage and control inventory, down to minute levels.