Glossary
Know the
language
Field service terms explained in plain English. Written for professionals who do the work, not students reading a textbook.
A
AFCI (Arc Fault Circuit Interrupter)
A circuit breaker that detects dangerous electrical arcs — sparks from damaged wiring — and shuts off power before a fire starts.
Air Changes Per Hour (ACH)
A measurement of how many times the entire volume of air in a building is replaced in one hour, indicating how leaky the structure is.
ASME A17.1 Inspection
The safety code for elevators and escalators that defines inspection requirements for all vertical transportation equipment.
B
C
Chain of Custody
The documented trail tracking a sample from collection through analysis, ensuring test results are legally defensible.
Code Violation
A condition that does not meet the requirements of the applicable building, electrical, plumbing, or fire code at the time of construction or current standards.
Creosote
A flammable tar-like substance that builds up inside chimneys from burning wood, and a leading cause of chimney fires.
L
Level II Chimney Inspection
A detailed chimney inspection including video camera scanning of the flue interior, required during real estate transactions or after chimney fires.
Load Calculation
A mathematical analysis that determines the heating and cooling capacity needed for a building based on its size, insulation, windows, and climate.
P
R
R-Value
A measure of insulation's resistance to heat flow — the higher the R-value, the better the insulating performance.
Recognized Environmental Condition (REC)
The presence or likely presence of hazardous substances or petroleum products on a property, identified during a Phase I Environmental Site Assessment.
S
T
Thermal Imaging Inspection
Using an infrared camera to detect temperature differences in building surfaces, revealing hidden moisture, insulation gaps, air leaks, and electrical issues.
Title V Septic Inspection
A Massachusetts-specific septic system inspection required before selling a property with a private septic system.
TRAQ Assessment
A Tree Risk Assessment Qualification methodology developed by the ISA for systematically evaluating tree risk.