What does IFR stand for?

I Follow Railroad (SAUS)

I Follow Roads (XSAL)

Ifrane - Morocco - Seismograph station code, US Geological Survey (SEIS)

IFR Systems, Inc. - Associated Press (SAG)

Image-to-Frame Ratio

Immediate Free Recall (PDAA)

Imported Food Regulations - British

Impulse Fast Reactor - Former USSR

Impulse Frequency Rate (VLIE)

Income Fund Reimbursable (SAUS)

Increased Frequency Reporting (SAUS)

Increasing Failure Rate

Incremental Financial Rate of Return

Indian Foodgrain Requirements - British

Industrial Fuels & Resources, Inc. (EFIS)

Infer - Telegraphy (PCTE)

In-Flight Refueling

Information Flow Rate (SAUS)

In-Frame Response - Automotive engineering - Electronics

Infrared

Infrared Filter Radiometer

Inspiratory Flow Rate - Physiology

Instantaneous Frequency - Indicating Receivers (IEEE)

Instant Failure Report (ACAE)

Institute of Fisheries Research - University of North Carolina

Institute of Food Research - British

Institut Federatif de Recherche - Federal Research Institute - France

Instituts Federatifs de Recherche - France

Instrument Fighter Rules (SAUS)

Instrument Flight Recovery - NASA

Instrument Flight Regulation (SAUS)

Instrument Flight Research (SAUO)

Instrument Flight Rules - Aviation

Instrument Flying Regulations (SAUS)

Insufficient Data For Reporting (WDMC)

Integral Fast Reactor - Nuclear energy

Interface Register

Interim Final Rule - RSPA (TAG)

Interleaved Frame Recording (SAUS)

Intermediate Free Recall (SAUO)

Intermediate Frequency Range (MCD)

Internal Function Register

Internationaler Frauenrat - International Council of Women

International Federation of Radio Officers (SAUO)

International Federation of Radio-Telegraphists (SAUO)

International Federation of Religions (SAUO)

International Fellowship of Reconciliation (SAUO)

International Fiction Review - A publication (ANEX)

International Fighter RADAR

International Film Representatives - Division of International Film Completion Corp.

International Financing Review - A publication

International Flyer Resources Ltd. - Vancouver Stock Exchange symbol

Interrupt Flag Register - Computer science (IAA)

Intrinsic Failure Rate (VLIE)

Isolated Flow Responder - Physiology