Tag
#safety
18 topics across all disciplines.
Relief and flare systems — what happens when pressure wins
How relief scenarios are worked out, why the governing case is rarely the obvious one, and why nearly every part of a flare exists to stop it becoming the hazard it was built to remove.
Fired heaters — an open flame next to a hydrocarbon inventory
How a furnace is arranged, why the process fluid and flue gas travel in opposite directions, what draught and excess air actually control, and why the purge before light-off is never negotiable.
Valve types — picking one for the duty, not the drawing
Gate, globe, ball, butterfly and check valves explained by what each is built to do. Why throttling with a gate valve destroys it, what double block and bleed means, and how check valves slam.
Valve actuation and fail position — deciding what happens when everything stops
Pneumatic, electric and hydraulic actuators, why a spring is what makes fail-safe possible, how fail open and fail closed are chosen per service, and what a positioner actually does.
Plot plan and equipment spacing — the drawing everything else inherits
What actually sets the distance between equipment, the four drivers that pull against each other, the pipe rack as the spine and how its tiers are allocated, prevailing wind and fired equipment, roads and containment, and why a plot plan mistake cannot be recovered downstream.
Access, operability and maintenance space — what the plant is judged on afterwards
Valve reach and stem orientation, why a chain operator is a confession, platforms and the dead-end with one ladder, headroom, bundle pull and rotor withdrawal, drop-out areas and davits, and the model review that is the last chance to find any of it.
Relief valve and flare piping — the 3 per cent rule, backpressure and reaction force
The piping engineer's half of overpressure protection. Why a relief valve inlet must be short and generous, what chatter actually is, built-up and superimposed backpressure and the 10 per cent limit, reaction force on an open discharge, flare header slope, and the car-sealed valve that must never be closed.
Lift plans and rigging basics — sling angle, centre of gravity, and the reasons to stop
What a lift plan has to state before anybody touches a spool, why the tension in a sling leg is not the load divided by the number of legs, how an offset centre of gravity behaves, and the short list of conditions under which a supervisor stops a lift regardless of who is waiting.
Supervising under a permit — the shift you signed for
Not what a permit is, which is covered elsewhere and free, but what changes when you are the person who signed it — what to verify at the work rather than on the form, the conditions routinely accepted and not met, why a gas test expires, and what handing back actually requires.
Vessels, exchangers and relief devices — the static equipment
What MAWP means and why it matters more than design pressure, how heat exchanger types differ, and why the relief device is the one protection that cannot be bypassed.
Hazardous areas — zones, gas groups and Ex protection explained
Why a light fitting in a refinery costs ten times a normal one. Zones and divisions, gas groups, temperature classes, IP ratings, and how to read an Ex certification label.
Earthing and bonding — several different jobs sharing one word
Why a plant has more than one earth, the difference between earthing and bonding, how the neutral earthing decision shapes the whole system, and why static bonding has almost nothing to do with fault current.
Distribution and the single line diagram — the map of the electrical system
How power gets from the grid to a motor, what transformers and switchgear actually do, why protection must discriminate, and how to trace a supply on a single line diagram.
Plant layout, paving and drainage — decisions you cannot undo later
What a plot plan is actually deciding, why paving and slopes matter more than they look, and why a plant has four separate drainage systems that must never meet.
Underground services and excavation — the part of the plant nobody can see
What is buried under a plant and how it is protected, why trench collapse is the hazard that kills, and why backfill compaction decides whether a road is still level in ten years.
Safety instrumented systems and SIL — the layer that acts on its own
Why protection is kept separate from control, what a SIL number actually measures, how voting trades spurious trips against missed ones, and why a bypass left in is the classic failure.
Risk assessment and the hierarchy of control
The difference between a hazard and a risk, why PPE is last and what that actually means on site, how a job safety analysis differs from a site risk assessment, why a high near-miss reporting rate is a good sign, and what stop work authority costs the first time somebody uses it.
Permit to work — how a plant decides a job is safe to start
What a permit actually is and what it is not, why proving an isolation matters more than making one, why confined spaces kill rescuers, and the ways a permit system quietly becomes paperwork.