Pre-ticked for falls, confined spaces, chemical and refrigerant lines and plant, with three rows written. HVAC is the trade that works inside the machine, which means the machine has to be locked off before you are in it.
Plant that starts on a time clock does not know you are in it
An air handling unit, a chiller or a cooling tower can start under automatic control with nobody touching anything, and the person inside it has no warning. Isolating at the local switch is not enough where the control system can call for the plant from elsewhere.
A personal lock, fitted by the person going in and removed only by them, is the control. It is the same principle as electrical isolation and it gets applied less rigorously in mechanical work, because the plant feels inert while it is standing still.
Refrigerant displaces air, and plant rooms are enclosed
Most refrigerants are heavier than air and will collect at low level in a plant room. They are not toxic in the ordinary sense, which is exactly why they are dangerous: there is no irritation, no smell to speak of and no warning before the oxygen concentration drops far enough to matter.
So the fixed gas detection and the mechanical ventilation get proved working at the start of each visit rather than assumed from the last one, and the charge gets recovered rather than vented before anybody breaks into a circuit. There is also a fire consideration people forget: some refrigerants decompose into far nastier products on contact with a flame, so brazing near an unrecovered circuit is its own event.
The riser is a confined space and the survey is per riser
A services riser is enclosed, not designed for continuous occupancy, and often has restricted access and poor ventilation, which is the confined space definition satisfied three times over. It rarely feels like one, because it has a door and a light.
Assess each riser rather than deciding once for the building, in the same way ceiling voids differ floor by floor. And note that the limb is work in or NEAR a confined space, so the person at the opening passing tools down is inside the category too.
The temperature limb was written for you
Work in an area with artificial extremes of temperature reads as a rule for cold stores and furnace rooms, and HVAC is the trade that commissions both. A running cold store, a plant room with the boilers live, or a roof plant deck in February are all inside it.
It is almost never ticked, and the control is simple and unusual: exposure time limits with a warm or cool area available, logged against the limit rather than left to whoever is getting on with it. People underestimate cold exposure badly, particularly while concentrating.
Filling a wet system starts a legionella clock
A cooling tower, a chilled water system or a domestic hot water service filled and left stagnant at ambient temperature during commissioning is close to ideal conditions for legionella growth, and the risk belongs to whoever filled it rather than to whoever eventually operates it.
So the fill is planned rather than done when it is convenient: fill late, circulate, dose and flush, or leave the system dry until it can be run properly. Handing over a system that has been sitting warm and full for six weeks transfers a problem rather than a building, and the person most exposed in the meantime is the commissioning engineer taking readings off it.
Common questions
Does ductwork installation need a SWMS?
Usually through falls over 2 metres, since most of it happens in ceilings and plant rooms, and often through the confined space limb for risers and tanks. Work on refrigerant circuits brings in the chemical and refrigerant lines category on its own account.
Is a services riser really a confined space?
Frequently yes, and it is one of the most commonly missed. Enclosed, not designed for anybody to stay in, restricted access, often poorly ventilated: that is the definition satisfied several times over. The door and the light are what stop it feeling like one.
Can I vent refrigerant instead of recovering it?
No. It gets recovered with equipment rated for that refrigerant, both because releasing it is an environmental offence and because doing it in an enclosed plant room creates an asphyxiation risk in a space you are standing in. Recovery records per circuit are the evidence it was done.
What isolation is needed before entering plant?
A personal lock fitted by the person entering, removed only by them, at a point that defeats automatic control rather than just the local switch. Plant that can be called by a building management system will start regardless of how still it looks when you climb into it.
Do I need a separate statement for commissioning?
Commissioning is a different activity from installation and it usually deserves its own, because the plant is live during it. That inverts most of the controls: during installation the plant is dead and the hazard is the height, during commissioning the plant is running and the hazard is the plant.