This is a common question we get when we are working at facilities where there is a mechanical refrigeration system…
Do my refrigeration technicians have to be “qualified electrical workers”?
Because that question is so broad, we always answer “Yes”, based on our experience around these types of processes, but it depends and here are the details of the “depends”.
In traditional manufacturing environments we tend to have “production” and “maintenance” personnel and these two groups are profoundly different in what they do and the hazards they face. In all of the ammonia refrigeration processes we have worked in, it seems these two roles are always merged, meaning that the same worker who starts a compressor very well may the same person who changes out the compressor motor or maybe even does the entire rebuild. It is an interesting dynamic that occurs in the ammonia refrigeration profession, but one which I have always been impressed with. These ammonia techs are like “race car drivers”… they know how to drive the car like a pro and how to build/fix every aspect of their race car.
But it is this dual role that places them into the “Qualified Electrical Worker” category. What does this mean?
Let’s use OSHA minimum electrical safety requirements as our building block in just what would an ammonia refrigeration technician needs:
1910.331(a) Covered work by both qualified and unqualified persons. The provisions of §§1910.331 through 1910.335 cover electrical safety-related work practices for both qualified persons (those who have training in avoiding the electrical hazards of working on or near exposed energized parts) and unqualified persons (those with little or no such training) working on, near, or with the following installations:
1910.331(a)(1) Premises wiring. Installations of electric conductors and equipment within or on buildings or other structures, and on other premises such as yards, carnival, parking, and other lots, and industrial substations;
1910.331(a)(2) Wiring for connection to supply. Installations of conductors that connect to the supply of electricity; and
1910.331(a)(3) Other wiring. Installations of other outside conductors on the premises.
1910.331(a)(4) Optical fiber cable. Installations of optical fiber cable where such installations are made along with electric conductors.
OSHA has defined a “Qualified person” as
one who has received training in and has demonstrated skills and knowledge in the construction and operation of electric equipment and installations and the hazards involved.
Note 1 to the definition of “qualified person:” Whether an employee is considered to be a “qualified person” will depend upon various circumstances in the workplace. For example, it is possible and, in fact, likely for an individual to be considered “qualified” with regard to certain equipment in the workplace, but “unqualified” as to other equipment. (See 1910.332(b)(3) for training requirements that specifically apply to qualified persons.)
Note 2 to the definition of “qualified person:” An employee who is undergoing on-the-job training and who, in the course of such training, has demonstrated an ability to perform duties safely at his or her level of training and who is under the direct supervision of a qualified person is considered to be a qualified person for the performance of those duties.
So with that OSHA minimum established, any worker who has to work on/around live electricity, MUST be qualified by their employer to do so. This does not mean that a refrigeration tech has to be “electrically qualified” to throw a breaker or a local disconnect switch for the purposes of LOTO on energy sources OTHER THAN ELECTRICAL. Let me explain, as this fine line exists and is often misunderstood:
Scenario #1:
A worker needs to lock out an ammonia liquid pump, as this pump is an “energy source” that the worker will need to isolate in order to do his/her work safely. The procedure for locking out this pump requires the AUTHORIZED WORKER (term used under LOTO programs) to turn off (e.g. OPEN) the local disconnect switch to the pump’s motor. This simple throwing of the disconnect activity is ALLOWED by “unqualified electrical persons” as part of the LOTO procedure.
Sceanrio #2:
Let’s say the worker(s) above has to actually “change out” the motor on this ammonia pump in their scope of work. They would use the same local disconnect as part of their LOTO; however, since this worker will be WORKING ON ELECTRICAL WIRING he/she MUST be deemed “qualified” by their employer. In fact, the means he/she will use to verify ZERO ENERGY STATE (ZES) for the electrical energy to this motor work will be VERY DIFFERENT than the worker in the first scenario. The worker in the first scenario (who is NOT working on the pump or its motor – just had to lock out the pump for other work to be done downstream of the pump) can verify ZES by using the START/STOP button(s) for the pump. The worker who will actually be working on the pump will have to meet the following, as a “qualified worker”
1910.333(b)(2)(iv) Verification of deenergized condition. The requirements of this paragraph shall be met before any circuits or equipment can be considered and worked as deenergized.
1910.333(b)(2)(iv)(A) A qualified person shall operate the equipment operating controls or otherwise verify that the equipment cannot be restarted.
1910.333(b)(2)(iv)(B) A qualified person shall use test equipment to test the circuit elements and electrical parts of equipment to which employees will be exposed and shall verify that the circuit elements and equipment parts are deenergized. The test shall also determine if any energized condition exists as a result of inadvertently induced voltage or unrelated voltage backfeed even though specific parts of the circuit have been deenergized and presumed to be safe. If the circuit to be tested is over 600 volts, nominal, the test equipment shall be checked for proper operation immediately after this test.
These two(2) requirements are what make LOTO different for a “qualified electrical worker” who is working on electrical energy sources and a traditional “authorized employee” who is locking out electrical to something like a conveyor so he/she can clean it at the end of their shift. The use of start/stop buttons for the conveyor cleaning by the non-qualified electrical worker (but an Authorized employee under the LOTO program) is perfectly acceptable. However, the qualified electrical worker who would change out this conveyor motor, MUST do TWO things:
- operate the equipment operating controls (i.e. start/stop buttons), AND
- use test equipment (a calibrated/rated volt meter) to test the circuit elements and electrical parts
So here is the bottom line…
If a refrigeration technician is changing out motors, opening electrical cabinets that exposes them to live wiring, etc., he/she MOST DEFINITELY needs to be QUALIFIED by their employer to do this electrical work (e.g. a “qualified electrical worker”). If the refrigeration technician has another “qualified electrical worker” do ALL the electrical energy isolation AND ZES verification (as described above), then he/she could do the motor work under LOTO AFTER the ZES has been declared by the Qualified Electrical Worker. ALL of the the electrical work done BEFORE the declaration of a ZES MUST BE DONE BY a “qualified electrical worker” and whoever the employer deems as “qualified” to do electrical worker are the ONLY ones allowed to be exposed to electrical hazards!
My last bit of advice… Electrical energy sources are ALWAYS treated as LIVE/HOT – UNTIL they have been VERIFIED to at a ZES! This goes for EVERYONE, even “qualified electrical workers”!!! So even when a “qualified electrical worker” is using their volt meter to verify the absent of voltage, ALL of their safe work practices and PPE requirmeents APPLY until such time the volt meter provides the verification.
In the words of my dearly departed friend John Collier…
“Electricity is lazy. It does not want to run your appliance, equipment, lights, etc. It is always looking for the easiest (least resistant) and fastest path to “ground” so it can go to ground and do nothing. If we allow ourselves to be that “path to ground” we are going to have a really bad day! As we are are actually quite good at being an electrical conductor”.