Final answer:
When removing a contaminated barrier and accidentally touching the surface beneath, you should immediately wash the area with detergent and warm water, then treat with NaOH or bleach for one minute. Additionally, promptly report any incidents to the teacher and follow appropriate disposal procedures for contaminated waste.
Step-by-step explanation:
If the surface below the barrier is inadvertently touched when removing a contaminated barrier, the most effective action to take would be to immediately wash the area with detergent and warm water without scrubbing. The skin should then be treated with 1 N sodium hydroxide (NaOH) or a 1:10 dilution of bleach for at least one minute. After this, proper documentation such as an accident report may be required, especially if there is a potential for an infection. Hands are a common vector for microbes to transfer and cause illness, so prompt and proper decontamination is crucial in a laboratory setting to prevent the spread of pathogens.
Additionally, contaminated waste must be disposed of correctly through incineration or autoclaving in a strong basic solution, and contaminated instruments must be thoroughly cleaned and soaked in a strong basic solution.
General safety guidelines in a laboratory also advise against eating or drinking, as table tops could harbor hazardous substances. When working with flames or heat sources, extra caution should be exercised to prevent accidents. In the occurrence of an incident or damage to materials, it is important to alert the teacher immediately.