As a student who has studied chemicals, it is interesting to see huge tankers carrying chemicals. If you observe these tankers closely, you will see symbols on these tankers. By understanding these symbols, one can prevent injuries, not just in chemical factories but also in offices, homes and places where chemicals are used. This is because it is not only the tankers that bear such information, other products have them too.
The picture above is of NH3 on NH17. NH3 is the chemical formula for ammonia. The photo was shot on one of India’s national highways NH17, one of the busiest and 7th longest in the country. The tanker has a lot of indicators on it. Let’s look at what these indicators mean:
- Rear lights – indicate the speed of the vehicle
- Reflective triangle – a warning of a vehicle ahead; shines in the dark when a vehicle behind it uses headlights
- Number plate – identification of the tank
- Chemical name – name of the chemical the tank is carrying
- Two hazard symbols (aka pictograms) – skull-crossbones and a diamond placard
Tankers like these are a usual sight on these roads, considering India is the 2nd largest producer of ammonia in the world. It’s not surprising because India has a huge population and it is also the 2nd largest in terms of agricultural output. The tankers are especially striking when they give off odor. We all know that ammonia doesn’t smell nice. Cosmetic products try to avoid it but every now and then you can smell it off of someone with some fresh dye on their hair. Cosmetic products often say ‘No ammonia’ or ‘Ammonia free’ for this reason. Ammonia is also used in fertilizers, cleaning products, explosives, dyes, water purification and a lot more.
Quick facts about ammonia
- Poisonous for short-term exposure, a 2,500 ppm (0.25%) concentration in air may be fatal within 30 minutes.
- Fire hazard at high concentrations and high temperature
- Water polluting as it easily dissolves in water and forms ammonium hydroxide
- Colorless gas
We can learn something about every chemical from the writing and symbols on the tanker that carries it. This tanker has the word ‘Liquid Ammonia’ on it, along with symbols of a skull-crossbones and a fire placard with the no. 2 in it.
The tanker in the picture is carrying liquefied compressed ammonia gas. A liquefied gas is a gas when packaged under pressure for transport is partially liquid at temperatures above – 50 degree C. Gay-Lussac’s law says that as the pressure goes up, the temperature also goes up, and vice-versa. Because it is pressurized, it is at a lower temperature too, so no external cooling needed.
The skull-crossbones symbol is that of a toxic/poisonous chemical and a diamond placard with a number on it needs a bit of an explanation.
The fire symbol on the diamond means that it is a flammable substance. The number on the diamond signifies which class the chemical belongs to, which in this case is Class 2. Class 2 substances are gases.
Mind you, the hazard symbol in this picture is an old convention. A pictorial list of old hazard symbols can be found here. It is now time that we speak about inequality in labeling chemicals.
In Rio de Janeiro in the year 1992, at the UN Conference on the Environment and Development, a consistent system was developed so that if anyone from any part of the world sees these symbols, they will know what it means irrespective of the country they belong to, irrespective of the culture or language they speak. This system is called the Globally Harmonized System (GHS).
In India, there were other related rules under Environment (Protection) Act, 1986 before it considered the idea of having a GHS, such as:
- Manufacture, Storage and Import of Hazardous Chemical Rules, 1989, 2000
- Chemical Accidents (Emergency Planning, Preparedness and Response) Amendment Rules, 1996
- Public Liability Insurance Act, 1991, 1992
- Health & Safety Related Laws & Regulations:
- Factories Act, 1948, 1987
- Explosives Act, 1889
- Gas Cylinder Rules, 1981
- Petroleum Act, 1934, Rules, 1976
- Motor Vehicle Act, 1988
According to Ministry of Environment and Forests, India, following rules were to be followed while labeling tankers carrying hazardous chemicals:
An occupier shall not handle a material which is hazardous for supply and transport unless the material is clearly marked in accordance with the following requirements, namely:
- diamond placard (read all its specifications here)
- on an orange rectangular panel (read all its specifications here), to be placed immediately adjacent to each placard displaying therein the United Nation number for the goods in black digits. (UN number is a four digit serial number assigned to the substance under the United Nations system.)
- the product name including the trade name, substance name, systematic chemical name and chemical identifiers such as Chemical Abstract Number, as applicable;
- the name and address of the manufacturer, importer, wholesaler or other supplier of the material, and including of any deemed necessary for traceability of the material to the manufacturer or producer;
- an emergency telephone number manned in Hindi or English twenty-four hours must be indicated on the container, iso-container or tanker; (Now you remember this one very clearly.)
- The following information on the substance, if it considered hazardous, namely:
- proper shipping name
- United Nation number
- hazard class
- secondary hazard
- packing group
- the labels shall be displayed on at least two sides of the container, iso-container or tanker or transport unit
In the year 2012, India was supposed to issue rules to implement GHS but there was no news after that. Five years later, in 2017, a committee was constituted to prepare a National Action Plan for Chemicals (NAPC). A draft as seen by Chemical Watch recommends the development of an inventory and registration scheme for chemicals and outlines plans to adopt the Globally Harmonized System (GHS) of classifying and labelling chemicals. Finally!