What alphabetic level is used when nuisance contamination is present only requiring the lowest form of chemical andor respiratory protection?

When nuisance contamination is present, the alphabetic level used is typically referred to as "Level A" for chemical protection and "Level D" for respiratory protection. Level D is the lowest level of protection, indicating that there is no significant risk of exposure to hazardous materials, and standard work clothes and respirators may be sufficient. This level is suited for situations where contaminants are only a minor irritant or nuisance.