What is the dust wipe clearance level for porches?

The correct dust wipe clearance level for porches is 40 µg/ft². This standard is established to ensure that lead dust levels are kept at a minimum, thereby reducing the risk of lead exposure, particularly in vulnerable populations such as children.

Dust wipe sampling is an essential practice in assessing lead hazards, and setting these clearance levels helps to determine whether a space, such as a porch, is considered safe for occupancy post-intervention or renovation. The choice of 40 µg/ft² reflects the understanding that outdoor areas, while potentially less contaminated than indoor spaces, still require rigorous standards to safeguard public health.

Choosing the right clearance level is crucial because it aids in maintaining a safe environment, and setting it too low might lead to unnecessary remediation work, while setting it too high could risk the health of occupants. The other levels provided in the options are either too high or do not reflect the established regulatory standards for outdoor porches specifically.