When posting of signs is infeasible (e.g. sewer manhole covers or aircraft panels) and where personell cannot inadvertently enter, such as those protected by locks or those that require tools to open.
No.
if the commander or functional manager determines that workers or other employees will not enter permit-required confined spaces under their control, and they have been prohibited from entering
assistance in evaluating confined spaces
confined space entry permit
The confined space attendant.
Improve the ventilation rate
prior to entering a permit-required confined space entry. Emergency rescue assistance must be coordinated and it must be ensured that the fire department is available, if required, to respond for the duration of the entry.
maintain continuous communication with all authorized entrants within the permit-required space, by voice, radio, telephone, visual observation or other equally effective means
If oxygen levels fall below 19.5% during a permit-required confined space entry, all entrants must stop work immediately and leave the confined space. No one may reenter that space until testing shows that adequate oxygen levels have been restored.
No it is not required ..
OSHA Standard 29 CFR 1910.146, Permit Required Confined Spaces
OSHA Standard 29 CFR 1910.146, Permit Required Confined Spaces