Gas leaks, crude method of testing, gas poisoning/fire

There is a news item which mentions about the death of 2 persons and hospitalization of 2 more due to inhalation of poisonous gas from a manhole. One of the deceased went inside the manhole to check gas leak. As it appears, no PPE was used by the victims. Few years back, I read a similar incident wherein one auto driver opened the petrol tank lid and tried to check the petrol with the help of a lit match stick which resulted in burn injuries on the face. Similarly in another incident, a person died when he tried to see the water level in an underground water reservoir. The person died though he was sitting on the top of the tank and lowered his head without actually entering into it.
The safe practice is to lower the gas monitoring instrument / gas drawing tube to the place of work and check for levels rather than allowing the person to enter in to it. If it is not possible for any measurement due to complexity of the approach for the instrument, then a person should enter only after wearing self contained breathing apparatus and safety belt and communication system under the watchful eye of another person at the entrance of the opening.
Few years back, I saw in NGC in a "Seconds from Disaster" episode, where flammable gas leaked from the line (which was deep inside a river), diffused into a weak sewage water line adjacent to it, passed through sewage line network, leaked outside through open manholes of the city and caused widespread explosions after it found an ignition source in the form of a spark generated by lifting and dropping of manhole by one of the municipal employee. This type of fire and explosion is beyond imagination of persons. But, there was an accident reported where sparks from gas cutting work ignited a gas leak. Rules insist upon maintaining minimum 15 m radial distance around hot works, to be free from any flammable materials/storages. There is nothing wrong in covering flammable material containers with asbestos cloth / wet cloth to prevent spraks falling on them and there is no need to feel shy of being extra cautious about safety.
Though, people doing/permitting such hot works without safety precautions question about the wisdom of maintaining safe distances, occurrences of fire incidents remind us to be extra cautious and to know that "Rules are for all to implement" and only fools (though they claim that they are knowledgeable and are in good management position because of their so called hard work) violate the rules.