Safety: The starting point for Frame 6 User Group meetings as well as plant operations

Review of safe work practices never gets old; there’s always something to learn. Over the last decade, safety has taken hold as a “religion” on the deck plates. Virtually no maintenance activities are undertaken today without a safety review—at US plants at least.

Co-chair of the Frame 6 Users Group, Jeff Gillis may be the ideal session leader on safety given his global perspective. He has engineering management responsibilities at ExxonMobil for generating equipment worldwide, which demands that he know both how other countries and cultures assure worker safety and what their regulations are. OSHA is not global, and America does not have all the answers.

The safety forum at last year’s meeting was one of the most meaningful ever at a user-group conference, in the editors’ experience. It ran from the opening bell to the morning coffee break—nearly two hours. Fire protection was the first topic. A user charged with replacing his plant’s Halon system wanted to know from attendees what they would do and why. He had been thinking CO2 but thought it expensive.

The moderator said his company prefers water mist today. Another user who had experienced a few Halon discharges and found it difficult to get refills, opted for CO2. The switchover was relatively simple, he said. Spray nozzles had to be modified but the piping basically was fine the way to was—except that the CO2 bottles took up more space than the Halon ones.

He was not familiar with safety procedures concerning door opening and entry with CO2 armed. It was brought to the group’s attention at this point that recent 6Bs, made in Belfort, France, are built to different standards than the legacy machines made here. They initiate a unit trip when you open the compartment door.

Another user said that during commissioning of his facility, the CO2 system was armed a little too early and the plant experienced a release with people in the compartment. Thankfully, no one was hurt. He suggested a lock on the CO2 valve or a blank flange to prevent such an accidental release.

Someone else offered that a challenge at his plant was getting operators to close the compartment door properly after entry. Not much protection from CO2 with a door ajar. Maintenance of door handles was stressed as at least part of the solution to avoid a safety breach of this type.

Problems encountered in identifying failing or failed sensors was another subject brought to the floor. Proper wiring is important the group was told. Be sure the temperature limit of your wiring is above the compartment temperature. Poor-quality conduit should be avoided, too. One contributor to the discussion said at his plant they wire sensors to relays to identify failed sensors.

Haz-gas detection was the next subject. An attendee said the detectors installed in his unit, made in Belfort, must be calibrated every 360 days or they go to a “false state.” Others in the room suggested a six-month interval, to be on the safe side. A user mentioned that his units run 12 to 18 months between maintenance outages. Because they can’t get inside to maintain their detectors, the instruments were moved outside the package.

In Europe, the owner/operators were told, a unit will trip if there’s no air flow through the package, to protect against a gas leak. This was considered too conservative by at least one user because you may trip the machine unnecessarily. He suggested a runback instead of a trip on haz-gas detection. About half of the users in attendance said they had in-package haz-gas detection capability. Most do not shut the gas valve as a first action when alerted; rather, they opt for a runback or fired shutdown.

Next topic was safety when performing maintenance on top of the unit. No easy fleet-wide solution given the variety of plant/equipment arrangements. Restraint systems require a free fall of 6 ft or so to work properly; plus, there’s a weight limit that may not be compatible with structural members at the tie-off point. Scaffolding may be the best solution in many cases.

One user created a diagram of tie-off points, where you need PPE, scaffolding, etc, because there typically are new safety personnel for each outage and they will interpret codes differently. Having this information available beforehand they know what’s required and won’t drive site people crazy.

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