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February 28, 2020

Cathodic protection systems must be maintained

An incident of a full bore rupture of an oxygen transmission pipeline occurred in France. Prior to the rupture there were no indications of any leak
The investigation determined that the rupture was caused by the presence of an extended thinning zone of the pipe due to external corrosion. This corrosion was due to:
  • The pipe was immersed under the groundwater table during a part of the year. Groundwater brings dissolved oxygen.
  • Coating was disbanded, thus cathodic protection was inefficient in this zone (shielding effect).
  • The groundwater was renewed by thermal convection in the disbanded area through coating faults, with draining of corrosion products. Thermal convection was due to temperature difference between soil and gas just after compressor discharge
Source: EIGA 2020: Day two recap https://www.gasworld.com/eiga-2020-day-two-recap/2018388.article#.XjPM6yilu6Y.twitter

February 24, 2020

CO2 can kill - Dont underestimate it

An accident occurred in a building where dry ice was produced and involved a CO2 storage tank.
A hissing noise was coming from the valve of a tank . This was a leak resulting from the power being switched off days earlier. The power switch off also unfortunately cut the power to the CO2 indicator in the room. A security guard who came to investigate the hissing noise,  died after exposure to high CO2 concentration.
Source:https://www.gasworld.com/eiga-2020-day-one-recap/2018387.article#.XjPLaAAsYeQ.twitter

February 20, 2020

Beware of CO!

On November 7, 2007 a Pipeline X-Ray Inspection Technician was fatally overexposed to carbon monoxide levels while he was working in a pick-up truck, bed mounted camper shell-type dark room. The deceased had been working earlier the same day x-raying pipe welds and developing the film on a large pipeline project. At the time of the incident, the employee was working inside of the dark room developing a series of x-ray films that had been taken earlier in the morning on the same day. The deceased was an experienced technician in the industrial x-ray field with many years of experience.
Significant Factors:
•Employee was working in a dark room mounted in the bed of a pick-up truck, developing x-ray film, when he was overcome by carbon monoxide gas.
•The investigation was able to determine that the source of the carbon monoxide was a gas powered portable generator that was being used to power the small camper-shell type truck mounted dark room. Air sample testing revealed that the levels of carbon monoxide exceeded 500 ppm when working conditions were re-created by investigators. Another contributing factor was the weather conditions, specifically the wind direction in regards to the location of the working location. The dark room was located down wind from the placement of the portable generator, on the truck tailgate. The wind speed on the date of the accident was estimated to be 25-40 mph.
Recommendations:
•Brief all employees on the facts and circumstances of this fatal mishap.
•Brief/retrain all employees on the danger of working around equipment that produce carbon monoxide.
•Require that all portable gas generators that produce carbon monoxide gas to be located a minimum distance of five feet from structures having combustible walls and/or other combustible material. Keep exhaust gas from entering an area through windows, door ventilation intakes or other openings. Remind employees to note the wind direction and always maintain good ventilation by keeping carbon monoxide producing equipment down wind from the working area.
•Install carbon monoxide alarms in the camper shell-type dark rooms.

Source: http://wyomingworkforce.org/