Use of SAE Type I Fluid as an Anti-icing Fluid - Civil Aviation Safety Alerts (CASA) No. 2019-09


All air operators and de/anti-icing service providers

File Classification No.: Z 5000-35
RDIMS No.: 15908545
Document No.: CASA 2019-09
Issue No.: 01
Effective Date: 2019-11-15


The purpose of this Civil Aviation Safety Alert (CASA) is to inform operators and service providers on the expected use of the SAE Type I fluid Holdover Time Guidelines when operating in ground icing conditions, including active frost. Furthermore, this document provides guidance to air operators on effective communication techniques when requesting Type I fluid application only.

Transport Canada (TC) is aware of a potential risk described in this CASA associated with the application of SAE Type I fluid Holdover Time Guidelines when Type I fluid is used as an anti-icing fluid. test

This CASA serves as an awareness tool to all stakeholders with recommended procedures to minimize safety risks for air operations in ground icing conditions.


Holdover Time Guidelines

TC annually publishes the Holdover Time (HOT) Guidelines ( Table 48 of the Transport Canada HOT Guidelines entitled Guidelines for the Application of SAE Type I Fluid specifies the correct application procedures to be used by the service provider when Type I fluid is used as an anti-icing agent.

While it is the responsibility of the service provider to ensure that the minimum volume of Type I fluid is applied to achieve a holdover time, it is the Pilot-in-Command’s (PIC) responsibility to ensure that the treatment requirements are clearly communicated to the service provider.

Failure to properly communicate de/anti-icing requirements could result in the Type I fluid being applied without a holdover time (i.e., a volume of less than the minimum volume required to achieve a holdover time for Type I fluid).

Recommended action:

Directors of safety, directors of operations, chief pilots, check pilots, pilot instructors, training providers and service providers should ensure that all staff involved in ground icing operations are aware of the following required procedures.

Use of Type I Fluid for the Purpose of Deicing

When ground icing conditions are not present or forecast, prior to deicing, flight crews should clearly communicate a specific treatment for Type I fluid (e.g., Airline 01, Brakes Set, Configured for Spray, Type I, Spoilers ONLY). In this case, the service provider will use as much Type I fluid as necessary to ensure the aircraft is free of frozen contamination (i.e. there is no minimum quantity when deicing surfaces). In this circumstance, a Holdover Start Time will NOT be provided to the PIC.

Use of Type I Fluid for the Purpose of Anti-Icing and using the Holdover Time Guidelines

When ground icing conditions are present, forecast or when operating in active frost conditions, the service provider will automatically apply the heated Type I fluid to ensure the aircraft is free of contamination as described in the deicing procedure above.

For anti-icing purposes, the service provider will apply at a minimum, an additional 1 litre/m2 (~2 gal./100 ft2) of heated Type I fluid to the surfaces after the frozen contamination is removed. This is necessary as the heating of the surfaces significantly contributes to the Type I fluid holdover times. A holdover start time will be provided to the PIC.

If a holdover start time is not provided by the service provider, flight crews shall assume that no anti-icing protection exists and therefore SAE Type I Fluid Holdover Time Guidelines cannot be used. When in doubt, ask.

Contact office:

For more information concerning this issue, contact Mr. Yvan Chabot, Flight Technical Engineer, Flight Technical and Operator Certification, Commercial Flight Standards, in Ottawa, by telephone at 613-990-1065, or by e-mail at

Document approved by

Robert Sincennes
Standards Branch

The Transport Canada Civil Aviation Safety Alert (CASA) is used to convey important safety information and contains recommended action items. The CASA strives to assist the aviation industry's efforts to provide a service with the highest possible degree of safety. The information contained herein is often critical and must be conveyed to the appropriate office in a timely manner. The CASA may be changed or amended should new information become available.