Final answer:
The NOT apply chemical using crack & crevice treatment being very careful because of the risks of contamination. The safest approaches involve removing the dishes yourself or informing the owner to do so, or postponing the treatment.
Step-by-step explanation:
The treating for German cockroaches in a cupboard where the owner forgot to remove the dishes is to NOT apply chemical using crack & crevice treatment even if being very careful. This scenario involves pest control, health and safety, and professional responsibility.
When dealing with pest control in environments where food or dishes are present, extreme caution is necessary to avoid contamination. If the dishes were not removed prior to treatment, the safest course of action would be to remove the dishes yourself before proceeding with treatment, or inform the owner so that they can remove them.
If removing the dishes is not an option, it might be better to leave and return another day when the area has been properly prepared. Applying chemicals, even with crack & crevice treatment, carries the risk of contaminating the dishes and potentially harming the health of the individuals using them later. As a professional, ensuring the safety of the household should be a priority, and seeking advice from your office on the proper protocol might be necessary.