Aviation Fuel Biocides: To Treat or Not to Treat, That Is the Question

NATA GA Fuel Handling Subcommittee  

Aviation’s current state, both general and commercial, is but one example of Covid-19’s deleterious effects.  Tank farm operators, into plane service providers and aircraft owners alike have experienced stresses previously unfamiliar to our industry as travel restrictions/quarantine requirements, budgetary re-appropriation and other factors have prompted many in the industry to reconsider asset usage.  From corporate flight departments and recreational pilots to airlines and FBOs, none are immune.     

An unfortunate side-effect is a dramatic increase in the number of stagnant aircraft, and the subsequent increase in requests for biocide treatment of Jet Fuel into aircraft fuel tanks to combat the potential pitfalls of reduced use. As a result, there have recently been several serious flight safety issues involving biocide treatments that were performed incorrectly. 

On the surface, biocidal dosage seems like reasonable preventative maintenance and a nice service offering to customers who are putting aircraft into long-term storage, but a deeper dive will reveal a more complex scenario and NATA’s GA Fuel Handling Subcommittee encourages FBOs and other into-plane fuel providers considering biocide treatment to “hold short.”   

This is primarily because biocide treatment of aircraft is an aircraft maintenance issue and not typically associated with retail fueling operations. When treatment does occur the specific Aircraft Maintenance Manual (AMM) shall always be followed to ensure an approved biocide is used, and the correct amount of biocide is properly injected.   

While Fuel System Icing Inhibitor (FSII), Corrosion Inhibitor/Lubricity Improver (CI/LI) and Static Dissipating Additives (SDA) have published dosage rates in Jet fuel specifications, biocide dosages are notably absent from ASTM D1655- Standard Specification for Aviation Turbine Fuels.  

What ASTM D1655 does say about biocides is their dosage rate must be declared and agreed upon by BOTH the purchaser and the service provider. It also says biocides are for controlled usage in that specific additives are only approved for use in specific airframes/engines, as defined in the Aircraft Maintenance Manual (AMM).   

If microbiologic growth (MBG) contamination is suspected in either into-plane refueling equipment tanks or fixed storage tanks the first step is to perform MBG testing. There are several commercially available MBG detection kits on the market, contact your fuel supplier for more information.   

If MBG contamination is confirmed, the typical course of action will likely include draining and cleaning the tanks where contamination exists, replacing the filter elements installed, and recommissioning the tanks following subsequent MBG testing with negative results.  

It is important to note that tank cleaning should only be performed by professionals who are trained and permitted for confined space entry and familiar with the specific cleaning procedures required for aviation fuel tanks. NEVER attempt to enter or clean a tank on your own.    

In conclusion NATA’s GA Fuel Handling Subcommittee recommendations are:  

  1. First and foremost, minimize the potential for MBG growth with good water management practices (e.g. routine water draining from tank bottoms, filter vessels and wing tanks). 
  1. Never add biocides to bulk storage tanks, or into-plane refueling equipment tanks /pumping systems. 
  1. Biocides are only to be introduced during “into wing” refueling operations at dosage rates prescribed within the specific AMM and agreed to by the owner/operator of the aircraft for airframe and engine configuration. 
  1.  To ensure proper dispersion, biocide shall only be added via dedicated equipment that is approved for biocide injection.  

In addition to the above, please contact your refueling equipment manufacturer, and/or fuel supplier for more information. Safe fueling!   

Marijuana & Safety-Sensitive Functions Don’t Mix

One thing is for certain, over the past 20 years our society has seen significant cultural evolution. Often cultural change then leads to changes in the laws and regulations that govern the way we do business. One area where these changes have possible significant safety and compliance impact is in the legalization, either completely or partially, of marijuana by various states.

Check out the following article from Whitney Sigafoose with NATA Compliance Services. This article appears in NATA’s Fall 2019 Aviation Business Journal.

Click here to read more.

Major Announcement Regarding Filter Monitors

A major announcement is being made by Airlines for America (A4A) with the publication of Bulletin 2019.1-Updated ATA103 Requirements for Filter Monitors.

This latest bulletin states that when released, ATA 103 revision 2019.1 would allow the continued use of filter monitors qualified to EI 1583 7th edition beyond the December 31, 2020 withdrawal of the EI 1583 specification.

While this is welcome news to the many fuel providers who utilize filter monitor elements for into-plane refueling operations, the A4A bulletin was clear to emphasize that the decision was being made on a “INTERIM” basis only and “that filter monitors have no future in commercial aviation and will be phased out.”

As to exactly when filter monitors are to be phased out is yet to be determined and depends on the data collected from the current testing and evaluation of new filtration technologies.

Until then, A4A advises “It is imperative that into-plane fueling providers continue strict adherence to the A4A Bulletin 2017.2 actions and the filter monitor operational parameters prescribed in ATA103.”

To review the complete A4A Bulletin 2019.1-Updated ATA103 Requirements for Filter Monitors, visit NATA’s Safety 1st Alerts and Industry Publications page.

Ensuring Compliance with Filter Monitor Requirements

In late 2017 it was announced that super absorbent polymer (SAP) filter monitor elements, would be phased out of aviation fuel filtration by December 31st, 2020. In response Airlines for America (A4A) published Bulletin 2018.1 which included several action items for facilities that operate to the ATA 103 standard (and NATA recommends for all facilities) that utilize filter monitor elements in aviation fuel systems. The compliance deadlines for the actions items in Bulletin 2018.1 have all passed and the following should now be in place:

  • All 2-inch diameter filter monitors upgraded to EI 1583 7th edition.
  • All 6-inch diameter out-to-in filter monitors upgraded to EI 1583 7th edition.

Click here for a full list of EI 1583 7th edition qualified filter monitor elements.

  • All 6-inch diameter in-to-out filter monitors converted back to EI 1581 Filter Water Separators.
  • Operating with 15psi maximum filter monitor differential pressure.
  • Nozzle screen cleaning incorporated into monthly inspections for refueling equipment fitted with filter monitors (see Bulletin 2018.1 for recommended procedures).
  • Differential pressure limiting device set points adjusted to 15 psi.

Transitioning from the Legacy Safety 1st Program to the New Safety 1st Training Center

If you are a current user of the legacy Safety 1st program, we want to clarify a few key details about how the legacy system differs from the new Training Center.

In the legacy system, students earned a single certificate (PLST or Supervisor). The new Safety 1st Training Center uses a ratings-based approach allowing students to earn ratings as they train.  Instead of a certificate that expires on a fixed date, the courses that make up ratings have individual expiration dates. This means that when recurrent training comes due, it will be spread out over time, helping to create a continuous training culture!


The best practice for transitioning from the legacy system is:

  1. Add your students into the new Training Center;
  2. But do not have them speed through the new courses. Just ensure they earn the ratings they need PRIOR to their legacy certificate expiring.

The goal is to create a continuous training culture, not require every rating to come due at once when it is time for recurrency.

As always, thanks for supporting NATA Safety 1st and do not hesitate to email us safety1st@nata.aero with any questions.

And if you are reading this asking yourself, “What is this new Safety 1st Training Center all about?” you can check it out here.

Transitioning to the New Safety 1st Training Center

With the recent launch of the Safety 1st Training Center we’ve had several inquiries about how an organization should move from the legacy Safety 1st System to the new Training Center, here are a few key points:

  1. All legacy Safety 1st certifications are valid until they expire. For students who are not yet certified but are currently training in the legacy system, we encourage them to finish.
  2. The new system focuses on ratings, not certificates.
    • This allows students to pace their learning and earn ratings as they go rather than a single certificate at the end!

With this in mind, the best practice for transitioning is to:

  1. Put all your students into the new Training Center now.
    • Allow them to take their time but be sure they earn any needed ratings PRIOR to their legacy certificate expiring.

This means that when recurrent training comes due, it will be spread out over time rather than due all at once, helping to create a continuous training culture!

As always thanks for supporting NATA Safety 1st and do not hesitate to email us safety1st@nata.aero with any questions.

And If you are reading this asking yourself “what is this new Safety 1st Training Center all about?” you can check it out here.

Third DEF Contamination Incident Highlights Need for Additional Training

Earlier this month, another jet fuel contamination event occurred at an FBO in Southwest Florida.  This latest incident marks the third time in less than two years that Diesel Exhaust Fluid, or DEF has contaminated the fuel supply of a jet fuel truck. In all three cases, multiple in-flight engine failures occurred, with the possibility of significant damage to aircraft fuel systems and engines. Fortunately, none of these cases resulted in an aircraft crash.

Following the first contamination incident in late 2017, NATA, through its Safety Committee, reviewed the risk of jet fuel contamination with DEF and created a free DEF Contamination Prevention training course. This most recent incident, however, highlights yet again, just how serious the DEF contamination risk is, and how it is still a very real threat. FBO’s and aircraft operators must be diligent in ensuring that staff are not only properly trained, but that company policies and procedures used to prevent DEF contamination are being followed.

The following Q & A highlights key information all FBOs and fuel providers should be aware of.

  1. What is Diesel Exhaust Fluid (DEF) and what is it used for?

DEF is a clear liquid containing a mixture of urea and demineralized water that is used to reduce emissions in modern diesel engine vehicles. DEF is designed to be used only in 2010 or later year vehicles equipped with Selective Catalytic Reduction (SCR) systems.

  1. How does DEF get into jet fuel?

Details of the latest incident are still pending, but in previous incidents, the identified risk occurs when DEF is inadvertently added to the fuel truck’s Fuel System Icing Inhibitor (FSII) storage tank and then injected into the fuel.

  1. What happens when DEF contaminated jet fuel is delivered to aircraft?

DEF reacts with certain chemical components in jet fuel to form crystalline deposits in the aircraft fuel system.  This can lead to a very high likelihood of inflight engine failure, damage to aircraft fuel systems and engines, and represents a serious risk to flight safety.

  1. What can FBO’s and other fuel providers do to reduce the risk of DEF contamination?

In addition to reviewing the FAA’s Office of Airport Safety and Operations, October 2018  letter on the inadvertent use of DEF instead FSII in aircraft, NATA’s Safety 1st DEF Contamination Prevention training recommends the following 4 actions:

  1. DEF & FSII should be stored in separate, locked locations with differently keyed locks. Keys should also be labeled and not kept on the same key ring.
  2. All staff should be trained on the locations of DEF and FSII and the differences between the packaging and labeling of the two products.
  3. Only trained and approved personnel should handle DEF or fill fuel truck DEF tanks.
  4. All FSII transfers from storage to refueling equipment FSII containers should be recorded in a dedicated log that includes
    1. Date
    2. Time
    3. Transfer to/from
    4. Name of individual who completed the transfer
  1. What should I do if I believe that aviation fuel has been contaminated with DEF?

Currently there is no field test to check jet fuel for DEF contamination, although it has been reported the industry is working on such a test. NATA recommends that all FBO’s and other aviation fuel providers work with their fuel distributer to develop a response protocol to aviation fuel contamination incidents. Such a protocol should include the training needs for FBO staff.

  1. How can my team access the NATA Safety 1st DEF Contamination Prevention training?
  • Companies that currently use the NATA Safety 1st program can simply assign the DEF training as they would any other course. There is no charge for the DEF training.
  • Companies that do not currently use the NATA Safety 1st program can contact us at safety1st@nata.aero for complementary access to the DEF program.


For more information or for additional questions please contact NATA at safety1st@nata.aero

Congratulations: American Aero FTW Becomes First FBO to Earn IS-BAH Stage III Registration

American Aero FTW, an FBO based at Meacham International Airport in Fort Worth, Texas became the first FBO in the world to earn a new Stage III safety and ground handling certificate of registration from the International Business Aviation Council (IBAC). IBAC’s International Standard for Business Aircraft Handling (IS-BAH) registration is a global, voluntary code of best practices for business aviation ground handlers. IS-BAH is a joint program between IBAC and the National Air Transportation Association (NATA). It incorporates the NATA Safety 1st ground audit program and a safety management system (SMS) in all aspects of FBO operations and is aligned with the International Standard for Business Aircraft Operations (IS-BAO). In 2015, American Aero FTW was the first FBO in the Western Hemisphere to the earn IS-BAH Stage I registration. In 2017, the FBO was one of the first in the world to earn Stage II.


“When I created American Aero FTW, I set forth to redefine the FBO experience for passengers and crews and deliver an exceptional customer experience at every touchpoint,” said American Aero FTW founder Robert M. Bass. “This milestone reflects that vision and demonstrates our commitment to deliver unparalleled safety and service.” Read more.

NATA Wraps Up Successful Second Annual Ground Handling Safety Symposium

Continuing its leadership role in driving general aviation ground handling safety initiatives, NATA concluded the second annual Ground Handling Safety Symposium (GHSS) on September 12, 2018. The NATA GHSS is the first industry event dedicated solely to general aviation ground handling safety and includes expert speakers, open forum discussions and industry incident case-studies to provide attendees an interactive experience.

Attendees explored the dynamics between just culture and individual accountability, the challenges of managing safety in a multi-generational workforce and the role of risk management in dealing with fatigue on the ramp. During the open forum sessions, moderated by members of the NATA Safety Committee, attendees discussed the common challenges affecting safety management system implementation, fuel contamination prevention, on-ramp usage of personal electronics and more.

In addition to the great sessions, discussions and case studies, NATA GHSS attendees were able to network with other safety professionals from across our industry at the networking event held at Top Golf in Ashburn, VA.

The 2018 NATA GHSS was made possible with the support of ServiceElements International, Facet Filters, Baldwin Aviation Safety, FBOPartners, Chubb Insurance and CrewID.

NATA Concludes First Certified QC Inspector Workshop

Last week, NATA held its first Certified QC Inspector Workshop at Wilson Air Center in Charlotte, NC. The two-day event focused exclusively on aviation fuel quality control and how to deliver clean, dry and on specification fuel to aircraft, through proper receipt, storage, and handling procedures.

The workshop was led by Steve Berry, NATA’s Trainer and Content Manager and Keith Clark, Phillips 66’s QC Technical Representative. Through classroom and hands-on sessions, attendees learned how to setup and organize fuel quality control records and documentation for the receipt of fuel and QC inspections. Attendees were also provided an industry update by Scott Drafall of Facet Filters on the status of the monitor filter issue.

NATA would like to thank Phillips 66, Facet Filters and Wilson Air Center staff for making this event possible. For more information on other upcoming NATA events, please visit www.nata.aero/events.


QC Technical Rep Keith Clark demonstrates the free water test using a Velcon Hydro-Kit.



Attendee Josh Matekovic of Clovis Airport in Texico, NM participates in the quarterly external water defense check of a filter/separator vessel.


Scott Drafall of Facet Filters provides attendees an industry update on the status of monitor filters.