Still waffling on interview clothes. I will definitely not be following Goldielocks' advice of "add jewelry and or polished accessories. Hair is 'done' fingernails groomed ( no paint ok). I would definitely wear a heel." Because that is sooooo far from me, and I don't even own any of that nonsense like heels. I'm curious if you are an engineer, Goldielocks, because wearing steel toe boots would be a more appropriate shoe choice for pretty much all the engineer interviews I have been on. I know I will be having a lab tour where closed toe shoes are definitely required, and I will have to put on toe clips if I am not wearing steel toes.
Ha! It depends on where you are interviewing. If I am interviewing at the manufacturing plant itself, then yes, I do bring my steel toe boots. They come with me, and are set down in the corner, because there is no way that I am leaving the interview without a chance to walk the floor. My work is consulting, so my interviews are with new clients, and therefore I get a lot of them every year.
Nearly all my jobs have been at least 60% of the time at the office, usually more, with the remainder as floor or "field" time. Usually distribution warehouses, sewage treatment plants, hospital laundries, bloodwork labs, food plants, etc, etc,. I don't do full time (by choice) at the construction site which is one of the places that khakis and a sweater set with steel toes would fit in well for an interview.
When I say heel, I am talking about a 1 inch, chunky heel, that you could teach a full day seminar in, walk around the hospital like the managers do, or walk across a grassy field without looking like an idiot. e.g., something nicer than a nursing loafer, and polished leather.
Your clothes should be dressier than normal work day, which is why I indicated accessories. I find that a necklace or scarf with a blouse and quality cardigan and dress slacks can work well, no suit required, if everything looks groomed. It quickly transfers into no jewelery, no scarf, steel toes and a lab coat to walk the floor, in about as much time as it takes the interviewer to find the visitor name tags. This is another reason I hate fancy suits -- you have to be more careful on the floor with them.
The key is to put out a decidedly "NOT A MOM" vibe, (which the last guy interviewed was not fighting with) so erring on the less comfy side may be in your favour. You indicated that you don't want to wear a suit or blazer, and that can be fine for women, if everything else is polished. Runswithmoney has the right idea for the interview.
If you are applying for a job moving boxes, operating a forklift, yelling at construction workers, or working with tools, then looking prepared to actually work is more important than looking polished. Your post made it seem like the type of engineering work you would want involved working with a computer at a desk, though, with a lab interview coming up, not drilling supervisor.