The refrigerant regulations recognize a category of allowable releases described as de minimis. Which situation fits that description?
- AEmptying a partly full recovery cylinder to the air before shipping it back to the supplier each spring
Emptying a cylinder to the air is an intentional release of a substantial quantity, and it has nothing to do with a recovery effort. A return shipment does not make it allowable.
- BBlowing refrigerant vapor through a line set to clear out debris after a burnout on a rack
Using refrigerant as a purge gas is a deliberate release whatever it is clearing. Dry nitrogen is the correct gas for blowing debris out of a line set after a burnout.
- COpening a charged system to the atmosphere because the recovery machine will not start that day
Equipment failure does not authorize venting. The correct response is to get working recovery equipment on site, however long that takes, rather than opening the system to the air.
- Tiny amounts that escape while the technician is making a good faith effort to recover the charge
Why D is correct
The allowance applies only to the small unavoidable losses that occur while a good faith recovery is under way. The technician must actually be trying to capture the refrigerant for the release to fall in this category.
What this question is testing
Tests whether the candidate can apply the de minimis concept narrowly and distinguish unavoidable trace losses from deliberate releases dressed up as minor.
On the job
This provision is what keeps ordinary recovery work legal, because no amount of care fully prevents the small loss when hoses come off. The trap on job sites is stretching the idea to cover convenience, especially when a machine is slow or the charge is nearly gone. Documented recovery, low loss fittings, and pulling hoses down before disconnecting keep a technician on the right side of the line.
Memory technique
De minimis is the drip left in the hose, not the charge left in the system.
Exam tip
De minimis always appears alongside a good faith recovery effort. If the scenario has no recovery attempt, the release is not de minimis.
Where to look it up
De minimis equals small unavoidable releases during a good faith attempt to recover refrigerant.