Worker dies of acid burns

In an incident, when four workers were cleaning an acid tank in a factory, acid and other chemicals fell on the persons and one died while others suffered burn injuries. It is not clear from the news report, how acid fell but clearly it is a work in confined space and one has to take all precautions for such jobs to avoid such incidents. The minimum precautions to be taken are,

1. List out safe procedure, job hazard analysis and ensure safety measures for identified hazards
2. Obtain safety work permit
3. Empty the contents from the tank by pumping / draining
4. Clean the tank by water circulation or with suitable medium and test for presence of acid by sampling the circulated water
5. Isolate all inlet lines positively by inserting a blind/slip plate and not by merely closing the valves as leaking of valves is possible
6. Display caution boards at the tank pump switches for not to operate and about the work in progress and if available, remove the fuses and keep in safe custody
7. Ensure LOTO
8. Open the vent lines and admit compressed air to ensure oxygen levels at the actual place of work same as that of atmospheric air
9. Use only 24 V supply for electrical fittings inside 
10. Provide proper access and illumination 
11. Ensure work area and escape routes are free from obstructions
12. Inform medical and fire teams about nature of work and location, before start of work
13. Ensure proper breathing air set suitable for use in case of emergency, or ensure BA set use during entire work
14. Follow buddy system by having one person outside to watch for every person inside
15. Ensure to engage only medically fit personnel for the job and brief the hazards, safety measures and emergency procedures to be followed
16. Carry out trial run before start of work
17. Ensure continuous competent supervision during entire period of work

http://www.thehindu.com/todays-paper/tp-national/article3902905.ece?textsize=small&test=2