OK, I will correct you. I don't know of a current film which can not be inspected if done correctly. I develop most of my 8x10 and 7x17 films by inspection.
For orthochromatic films I use a 7 1/2 wat red bulb 5 feet from the tray and leave it on continuously.
For panchromatic films I use a 7 1/2 watt dark green bulb made for the purpose 5 feet from the tray. Inspections are short, on the order of 2-3 seconds. The first inspection is after the film has developed for 60-65% of the estimated time. It usually takes no more than 3 inspections to get the film where I want it.
Looking at the emulsion will give false information and the film will be under-developed. The base side must be inspected and one looks first for the highlights.
Begin by turning off the light for at least 5 minutes prior to beginning development. If this is done, the dim green light will look like a floodlight.