Let’s poka-yoke lives of STP operators

Poka-yoke* is a simple Japanese quality principle from the 60s--the use of any automatic device or method that makes it impossible for an error to occur. It is a simple idea. 'Simplicity' always wins! 

Now, let's switch to STP operators and poka-yoke! 

Manual scavenging is still widely prevalent in India.The recent Tehelka article, Dalits still sent to die in gas chambers was condemned by many for its headline but the fact is, hundreds die in septic tanks, gutters and sewers. Movies like Kakkoos and Lesser Humans have exposed the atrocities they face. 

In the western world, the entire sewer cleaning exercise is 'mistake proofed'; they wear Dupont bunny suits with respiratory kits, the sewers are well lit, mechanically aerated with huge fans and therefore not so oxygen-deficient. In Hong Kong, a sewer worker needs to have at least 15 licences and permits in order to enter a manhole and of course absolutely no alcohol consumption before entering! These are mandatory mistake-proofing tactics which simply save lives. 

The lives of sewage treatment plant operators are worse as they live in STPs day in and day out. As you all maybe aware, three STP operators died in an apartment STP recently in Bangalore. There is panic among residents' associations now as, after the incident, the managing committee members were arrested and put behind bars--many of them have no clue on STP operations. 

Apart from other issues like being power-intensive, heavy on maintenance, difficult to manage etc, the conventional motor-based STPs relies on labour to enter the tanks to clean up regularly, most of whom enter without sufficient protection.  

We have seen hundreds of STPs. The fact is that none of us can stand in an STP room for more than two minutes without feeling suffocated. We would like to share some guidelines for apartment associations that will prevent such mishaps from happening. 

1. Buy an alcohol tester and keep it handy:

2. Educate operators about carbon monoxide:

3. Ensure safety is part of the training:

4. Ensure emergency information and first aid box are kept handy:

5. Ensure exhaust fans are working:

6. Ensure safety gear is used:

7. STP area should be designed for safety:

8. Stop tinkering with STP equipment:

9. CCTV in STP areas:

10. Legal contracts in place:

Outside of this, we would highly recommend that real estate developers, pollution control board, RWAs and citizen groups keep themselves informed about STPs that run without power or machines, without risks and issues of maintenance. There are a few, but good players in the market that treat sewage through bioremediation. It is up to them to make the shift and adopt these technologies for a safer, healthier, cleaner future. 

Endnote

*Poka-yoke: As per Wikipedia, poka-yoke is a Japanese term that means "mistake-proofing" or “inadvertent error prevention”. The key word in the second translation, often omitted, is "inadvertent". A poka-yoke is any mechanism in a lean manufacturing process that helps an equipment operator avoid (yokeru) mistakes (poka). The concept was formalised by Shigeo Shingo as part of the Toyota Production System. 

Some examples are the Antilock Braking Systems (ABS) for drivers who stomp on the brake, 'Beware of Dog' signs or the railway tap which gives water only when pressed. One crazy example is a patient about to undergo surgery for a problem on his right arm has 'wrong arm' written with a marker pen on his left arm as he is worried about any potential mistakes by surgeons. Similarly, once a bank mandated their tellers to record eye colour on bank transaction form to ensure eye contact! Rumour has it that they were looking for some poka-yoke ideas to make tellers smile too! 

About authors

Dr E.Muralidharan

Tharun Kumar

The views and opinions expressed in this article are those of the author/s and do not necessarily reflect the policy or position of India Water Portal.