Relying on ingredients when you know more information

[ralph.lasry]

Please see…

Non-Hechsher Kashrut

I haven’t been able to find this basic question asked anywhere: how does one square going off of ingredients only, when there are such plants that will process other treif ingredients, but will obviously not be listed on the packaging? Don’t we have to also make sure the equipment is also kasher? Thanks in advance.