Inspection Planning, Sampling Design, and Documentation
Planning Before Fieldwork
The candidate must know how to plan an inspection or risk assessment before touching a surface. Key planning elements include: reviewing the client's objectives (inspection versus risk assessment versus clearance), obtaining building history and prior reports, identifying the age of the structure, determining the number of dwelling units and common areas, and confirming access and occupant notification. Occupant protection and notification are part of planning, not an afterthought.
Sampling Design Concepts
- Component-based sampling: testing each distinct building component (e.g., window sill in a bedroom) by substrate and condition.
- Random sampling: selecting a statistically valid subset when testing every component is impractical; the sample size must be defensible.
- Worst-case sampling: selecting the components most likely to be deteriorated or accessible to children.
- Composite sampling: combining samples to reduce cost, but composites cannot identify which component is positive and are generally not used for clearance.
Documentation
Every sample needs a unique identifier, location description (room, component, substrate, condition), date, sampler name, and method. A chain-of-custody form tracks possession from collection to laboratory. Photographs and sketches supplement written records. Incomplete documentation is the most common reason a report fails.
Traps in Questions
Watch for confusion between inspection (identify LBP and its location and condition) and risk assessment (evaluate hazards and recommend response actions). Another trap is using composite sampling for clearance, or assuming a single sample per room is sufficient regardless of component diversity.
Rule of Thumb
If the objective is a clearance exam, sample every component that was disturbed and document each one individually - never composite.