Arizona apparently requires it, at least Maricopa County - every place I have been in makes their production/line employees get one.
How bizarre! Curious who has what jurisdiction in AZ in terms of retail, restaurants, and manufacturers.
It depends state-by-state. for example, Oregon doesn't have food handlers as a requirement for manufacturers, only restaurants. However, even the restaurant scoring system doesn't treat not having the permit as a violation, so even restaurants, though they're supposed to, have no actual penalty for not doing it in Oregon.
Looking at the Idaho food code:
First, seeing if it applies to you:
These Rules Apply to FOOD Establishments. FOOD ESTABLISHMENTS as defined in Section 39- 1602, Idaho Code, must follow these rules. Those facilities include but are not limited to the following:
OD, water and BEVERAGE processing and bottling facilities that manufacture, process and distribute FOOD, water and BEVERAGES within the state of Idaho, and are not inspected for FOOD safety by a federal agency.
So, are you inspected by FSIS or FDA? In which case you're subject to the CFR and exempt from idaho food code requirements (though probably not in practice given that your "FDA inspector" is probably a state inspector contracted by FDA.
If you sell within state boundaries, then you're subject to the code. On the subject of handlers permits, I don't see any requirements for all employees, but there is one for the "Person in charge"
IDAPA 16.02.19.201 ASSIGNMENT OF PERSON IN CHARGE Modification to Section 2-101.11(A). The LICENSE HOLDER will be the PERSON IN CHARGE or will designate a PERSON IN CHARGE and will ensure that a PERSON IN CHARGE is present at the FOOD ESTABLISHMENT during all hours of FOOD preparation and service
DEMONSTRATION OF KNOWLEDGE Modification to Section 2-102.11(A). The PERSON IN CHARGE of a FOOD ESTABLISHMENT may demonstrate knowledge on the RISKS of foodborne illness or health HAZARDS by one (1) of the following:
A) 2-102.11(A) MODIFIED BY IDAPA 16.02.19.210.01 DEMONSTRATION OF KNOWLEDGE No Critical Violations. Complying with the 2013 FOOD Code by not having any critical violations at the time of inspection. Pf
(B) Being a certified FOOD protection manager who has shown proficiency of required information through passing a test that is part of an ACCREDITED PROGRAM. Pf © Responding correctly to the inspector's questions...
So whomever is in charge during production hours (maybe a day and night shift as well as a backup) needs to be able to demonstrate they have the necessary knowledge either by having the certificate or being able to answer questions/have no critical violations.
So as far as getting all of your line employees food handlers cards, you aren't required to per the ID food code or FDA (though they do need some type of training), and you can either get an accreditation for yourself/managers to placate your inspector, or fight them on demonstration of knowledge.
As with PCQI training, i'd recommend getting the cert as one less thing to fight about during the audit. :)