Up till two decades ago, news reports of exploding pressure cookers were rather common. Though they were an incredible time-saver, the dangers associated with them lingered in the back of every homemaker’s mind while cooking with them. The regulatory authorities and manufacturers have taken immense efforts to improve the standard features of pressure cookers and to allay the fears of the consumers. Today, as a result, instances of pressure cooker explosions are rare.
The standard safety features to be incorporated into a stovetop pressure cooker are encoded in the BIS standards. And that is why you shouldn’t buy a pressure cooker unless it has a BIS mark.
All manufacturers are expected to follow the safety standards stipulated by BIS and batch-wise inspections are done to ensure these regulations are followed.
In fact, CCPA, the regulatory body had recently cracked down on major e-commerce portals and found brands like Amazon basics, Pristine, Quba and more were selling substandard pressure cookers that did not adhere to BIS standards. These brands have stopped selling online. But yet fact remains that many of these brands have been on the market as early as 2014. Some of the user reviews also indicate cases of such substandard pressure cookers exploding too.
Popular brands like Prestige, Hawkins, Pigeon etc adhere to standard safety regulations and so, you can expect them to be safe for use. So, if you have a pressure cooker without a BIS mark, it would be in your best interest to chuck them out. If in case you bought a pressure cooker from any of the substandard brands mentioned above, you can contact the manufacturer or the e-commerce platform itself and get compensated for it.
So what do the BIS standards entail in terms of the safety standards? Let us explore.
Safety Standards That BIS Mandates
The Bureau of Indian Standards has mandated the incorporation of numerous safety features into a pressure cooker’s design. And they constantly upgrade the standards to ensure optimal performance and safety. Not only does it save consumers money, but also prevents safety hazards.
The standards mandated by BIS talk not only about the safety features but also the quality of raw material used for making pressure cookers. For example, pressure cookers should be made of 302 or 304-grade stainless steel. If it is aluminium or its alloys, the grade, composition of other elements and tensile strength are mandated by BIS. The thickness of the anodized coating and its hardness are also dictated in the BIS.
We shall explore in detail other features that BIS mandates which ensure pressure cookers are safer nowadays.
Fusible Plug/ Safety Valve
To prevent accidents, BIS mandates having a safety pressure relief device on the lid of every pressure cooker.
A pressure cooker maintains a pressure of 1 bar. Whenever it exceeds this level, it releases the pressure through the vent tube. One of the main reasons why pressure cookers burst is because the vent tube ( on which you place the cooker’s pressure regulator weight) gets blocked due to food particles. In such cases, when the pressure can’t be released, the safety valve will melt before the pressure reaches thrice the permissible level. This lets out the excess pressure and prevents the cooker from bursting.
In most domestic pressure cookers, we see it in the form of a safety valve. Instead, a resettable type of pressure relief device is also allowed.
As per BIS, the bursting pressure of a cooker should be 6 times greater than the nominal cooking pressure. So, it should not burst till the pressure inside reaches 6 bar. Considering that the cooker’s safety valve melts when the pressure reaches 3 bar, the chances of it bursting is close to nil, unless the safety valve fails.
Lid Opening Under Pressure
Grave accidents can occur if you open a cooker that is filled with pressure. BIS mandates that users shouldn’t be able to open the cooker’s lid unless a force of 120N is applied. To get an idea, that is the force that 12 Kg of an object would exert if it is kept in your hand. You will be able to open the cooker using lesser force only if the pressure inside falls below 0.18 bar.
Pressure Regulating Device and Vent Pipe
As mentioned, blockage of the vent pipe is one of the leading causes of pressure cooker bursting. To prevent such incidents, BIS mandates the vent pipe should be at least 2mm in diameter. Also, it is designed in such a way to prevent clogging while cooking is in progress. Further, there should not be any linkage between the weight and the vent pipe. Also, its design should be easy to clean so that any obstructions will be easily visible and can be drawn out immediately.
Tips For Consumers For Using Pressure Cookers Safely
Most accidents related to standard pressure cookers happen nowadays due to human errors. To prevent such accidents, here are some easy to follow tips.
- Ensure that the tube vent of the pressure cooker lid is not clogged before every use. To check it, raise the lid to your eye level and look through the vent pipe and you should be able to see through it.
- While cooking dal and food that froths, add a spoon of oil so that the froth doesn’t clog the vent pipe.
- Before putting on the cooker weight, ensure that steam comes out through the vent freely.
- Do not use pressure cookers for pressure frying.
- Do not fill the pressure cooker to more than 2/3rd of its net capacity. While cooking rice or food that expands, avoid filling it to more than 1/2 of its net capacity.
- Prestige pressure cookers have a gasket release system whereby the gasket compresses and steam escapes through a small hole at the edge of the lid. Ensure that the pressure cooker is placed on the stove with the gasket release system facing away from you.