Hormone Replacement Therapy
Hostage Rescue Team
High-Resolution Tracker
Hartwell Railroad
Hartwell Railroad Company
Heidelberg retina tomograph
Heidelberg Retinal Tomography
hydraulic retention time
hydraulic retention times
ARRHYTHMIA RESEARCH TECHNOLOGY, INC.
Chartright Air
Habitual Residence Test
half-relaxation time
Handrail Removal Tool
Hard Real-Time
Harm Reduction Therapy
harringtonine
Hazard Review Template
heart rate
heart rate threshold
heart rate turbulence
Heat-Resistant Temperature
Heidelberg Retina Tomography
Heidelberg Retinal Tomograph
Heidelberg Retinal Tomographer
High Rate Tape
High Rate Telemetry
high-resistance training
high-resolution telemetry
Highway Regulating Team