Safety Recommendations Data Field Descriptions

The NTSB may issue safety recommendations at any point during the investigation of transportation accidents or crashes and in connection with safety studies. Recommendations specify actions that recipients can take to help improve safety by addressing a specific issue uncovered during an investigation or study. Letters containing the recommendations are sent to the organization best able to address the safety issue, whether it is public or private.

CAROL (Case Analysis and Reporting Online) is our search tool for investigations and safety recommendations across all modes. Future enhancements will include improved access to docket items as well. CAROL includes all recommendations issued by the NTSB.

CAROL works in all modern browsers.

Search Capabilities

CAROL enhances the database search process on ntsb.gov. You can search data by:

  • SIMPLE SEARCH, which allows you to search using a selection of fields from three categories: (1) Common Investigation Fields (2) Aviation Investigation Fields (3) Safety Recommendation Fields.
  • ADVANCED SEARCH, which allows you to build custom searches by selecting from a variety of investigation and recommendation fields. You can select whether to display results that match any or all of your individual query rules, or group your rules so results match any or all of the multiple rules in your grouping.
  • PUBLISHED SEARCHES, which allows you to view already published popular searches on topics such as safety recommendations associated with the Most Wanted List (MWL). These canned searches show dynamic data reflecting current information in the database each time you open them.

CAROL includes both investigative and recommendation data.  When using these search options, you first choose whether to view the results as a list of investigations or recommendations. Remember, the recommendations view provides a complete data set, if you only search Safety Recommendation Fields. The investigations view only displays the investigative records that have been created in the system. For aviation investigations, records from 1983 through the present are available. For investigations in other modes, data from 2010 through the present is available.

Because not all investigation data is available in CAROL, when searching for safety recommendations, always choose the Recommendations option in the Search for menu. For complete recommendation results use the Recommendations option in the Search for menu and only search on Safety Recommendations Fields.

Starting your Safety Recommendations Search using ADVANCED SEARCH

​​To begin, visit the CAROL homepage and click the ADVANCED SEARCH option from the top navigation bar and select the circular button to the left of the Recommendations option in the Search for menu.

You can select whether you want your results to match all of your search rules or any of your search rules. In the field labelled “Find results that match (ALL or ANY) of the following rules:” select the ALL option to have your query provide results that match all of your rules. Select the ANY option to have your query return results that match at least one of your rules.

To add a rule to your query, click the down arrow on the Field box. This shows the field options in a drop-down menu. The fields for the safety recommendations options are described below.

Your results will be displayed as a list of recommendations.


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Field Descriptions – Safety recommendations – Admin info

Safety recommendation ID

Safety recommendation ID refers to the recommendation number. This ID starts with a letter that corresponds to the recommendation mode. A for aviation, H for highway, I for intermodal, M for marine, P for pipeline, and R for railroad. The letter is followed by a dash. Then there are two numerals that represent the calendar year in which the recommendation was adopted. This is not necessary the year that the recommendation was issued. These two digits are followed by another dash. Then there are three numerals that represent the order in which the recommendation was adopted in that year and in that recommendation mode. For example, M-11-021 is the twenty-first marine recommendation adopted in calendar year 2011.

This field is available on the SIMPLE SEARCH, and ADVANCED SEARCH. Both SIMPLE SEARCH and ADVANCED SEARCH are flexible in accepting SR numbers. You can omit the dashes. You can also omit the lead-in zeroes in the last three digits of the SR number. You cannot omit any zeroes in the adopted year portion of the SR number. For example, for M-09-001 you can enter:

  • M-09-001
  • M-09-01
  • M-09-1
  • M09001
  • M0901
  • M091

But you cannot enter M91 to receive M-09-001. If you enter, M91 you will receive all the marine recommendations adopted in 1991.

In the ADVANCED SEARCH, you can enter partial recommendation numbers, such as M-11- , if you select the Condition contains. Searching for M-11- or M11with the Condition contains will return all marine safety recommendations adopted in calendar year 2011.​

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Recommendation text

Recommendation text refers to the text of the recommendation sent to the recipient or recipients. This field is available on  SIMPLE SEARCH and ADVANCED SEARCH. Using  SIMPLE SEARCH you can enter one or more words to search the recommendation text. Using  SIMPLE SEARCH both words must appear in the recommendation text for a result to be returned, but the words do not need to be sequential. Using  ADVANCED SEARCH, you can choose the Condition contains, does not contain, is, is not, starts with, or ends with. In  ADVANCED SEARCH, multiple words must appear in sequential order in the Recommendation text to appear as a query result.

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Addressee name

​Safety recommendation letters are addressed to the entity best able to act on a problem, whether it be public or private. Addressee name is a non-standardized text-entry field. Names of specific agencies, organizations, states, or cities may be used, and reflect the name at the time the recommendation was issued.

United States Department of Transportation Office of the Secretary and all DOT modal agencies are listed as acronyms in both the Addressee name and the Addressee acronym fields. For example, DOT, FAA, FHWA, FMCSA, FRA, FTA, and NHTSA. United States Coast Guard is also listed as an acronym (USCG) in both the Addressee name and the Addressee acronym fields. All other entities are listed using their full names.

Federal government agencies are listed starting with the cabinet level agency. For example, United States Department of Commerce, National Oceanic and Atmospheric Administration, National Weather Service. Addressees for agencies within a state or commonwealth begin with the state or commonwealth name. For example, State of Georgia, County of DeKalb, Police Department, Special Operations.

If you aren’t sure of the name used in the database, type a partial name and use the Condition contains. Then re-do the search with the full correct name, after you obtain it. While addressees are identified individually in the database, the actual letter salutation may show addressees only in the aggregate.

The Addressee name field is available in the ADVANCED SEARCH and the SIMPLE SEARCH. On  SIMPLE SEARCH  both words must appear anywhere in the Addressee name for a result to be returned, but the words do not need to be sequential. On ADVANCED SEARCH, you can choose the Condition contains, does not contain, is, is not, starts with, or ends with. In the ADVANCED SEARCH, multiple words must appear in sequential order in the Addressee name to appear as a query result.

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Addressee category

This field is only available on  ADVANCED SEARCH. Each addressee in the database is assigned an Addressee category. The Addressee category options are Associations, Federal Government, Foreign, Local Government, Private Industry, State Government, and Union. The Condition options for Addressee category are is and is not​.

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Correspondence text

​This free text search field is only available in  ADVANCED SEARCH. It searches the text of the correspondence we have sent to the recommendation recipients and the text of the correspondence the recipients have sent to us. On the ADVANCED SEARCH, you can choose the Condition options contains, does not contain, is, is not, starts with, or ends with. Multiple words must appear in sequential order in the Correspondence text to appear as a query result.

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Correspondence type

​This field is only available in  ADVANCED SEARCH. It is a drop-down menu field with the Condition options is and is not. It allows you to limit your search to recommendations whose correspondence history contains or does not contain correspondence entries in any of the six available categories. The six Correspondence type options are defined below.

Non- Recipient Correspondence: A relevant letter received from an organization that did not receive the recommendation.

NPRM Response: NTSB’s response to another Federal agency’s Federal Register notice. When our response letter references a safety recommendation, the relevant portion of the response letter is entered into that recommendation’s correspondence history.

Official Correspondence: The most common type of correspondence entry. An official response letter received from the recommendation recipient or NTSB’s official reply to the recommendation recipient’s letter.

Reiteration: A correspondence history entry describing a reiteration of the recommendation.

​​Report Reclassification: A correspondence entry describing the reclassification of the recommendation that occurred in an investigative report or study and not in the usual recommendation classification letter, which are independent of investigative reports and studies.

Transmittal Letter: A correspondence entry of the initial transmittal letter sent to the recommendation recipient, informing them of the recommendation. ​

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Field Descriptions – Safety recommendations- Status

Overall open/closed

This field is only available in the ADVANCED SEARCH. It allows you to search whether the overall status of a recommendation is open or closed. (“Open” and “closed” each include multiple statuses). 

The “Open” statuses are:

  • Open—Acceptable Response,
  • Open—Acceptable Alternate Response,
  • Open—Unacceptable Response,
  • Open—Response Received, and
  • Open—Await Response.

The “Closed” statuses are:

  • Closed—Exceeds Recommended Action,
  • Closed—Acceptable Action,
  • Closed—Unacceptable Action,
  • Closed—Unacceptable Action/ No Response Received,
  • Closed—Reconsidered,
  • Closed—No Longer Applicable,
  • Closed—Superseded,
  • Closed—Acceptable Action/ Superseded, and
  • Closed—Unacceptable Action/ Superseded.

​For multiple recipient recommendations, the overall status is the status of the plurality of open recommendation recipients, if there are remaining open recipients. The plurality means the status most often encountered but not necessarily the majority. Here’s an example with 7 open recommendation recipients:

  • 1st recipient: Open—Acceptable Response
  • 2nd recipient: Open—Acceptable Response
  • 3rd recipient: Open—Unacceptable Response
  • 4th recipient: Open—Await Response
  • 5th recipient: Open—Initial Response Received
  • 6th recipient: Closed—Acceptable Action
  • 7th recipient: Closed—Acceptable Action

​The overall status would be Open—Acceptable Response because it is the plurality of open recipients. It is not the majority because in this case there is no majority of open recipients; only 2 out of 5, not 3 out of 5, are in Open—Acceptable Response status.

​If all the recipients are closed, the overall status is the status of the plurality of all recipients. For single recipient recommendations, the overall status and the addressee status are the same. The Condition options for Overall open/closed are is and is not.

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Overall status

​​This field is only available in ADVANCED SEARCH. It allows you to search on the overall status of safety recommendations. In the Query value field, you choose from the list of all statuses.

For multiple recipient recommendations, the overall status is the status of the plurality or open recommendation recipients, if there are remaining open recipients. If the recommendation is closed for all the recipients, the overall status is the status of the plurality of all recipients.

For single recipient recommendations, the overall status and the addressee status are the same. The Condition options for Overall status are is and is not.

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Addressee open/closed

​This field is only available in ADVANCED SEARCH. The addressee status refers to the status of the recommendation to an individual recipient. The overall status and the addressee status are the same if there is only one recipient for a recommendation. If there is more than one recommendation recipient, the addressee status can vary from the overall status. This field allows you to select whether the addressee status is an open or a closed classification status. “Open” and “closed” each include multiple statuses. The “Open” statuses are:

  • Open—Acceptable Response,
  • Open—Acceptable Alternate Response,
  • Open—Unacceptable Response,
  • Open—Response Received, and Open—Await Response.

The “Closed” statuses are:

  • Closed—Exceeds Recommended Action,
  • Closed—Acceptable Action,
  • Closed—Unacceptable Action,
  • Closed—Unacceptable Action/ No Response Received,
  • Closed—Reconsidered,
  • Closed—No Longer Applicable,
  • Closed—Superseded,
  • Closed—Acceptable Action/ Superseded, and
  • Closed—Unacceptable Action/ Superseded.

The Condition options for Addressee open/closed are is and is not.

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Addressee acronym​

​This field is only available in  ADVANCED SEARCH. It allows you to search on the addressee acronym in a free text search field. You can choose the Condition options contains, does not contain, is, is not, starts with, or ends with. Not all Addressee name entries have an entry in the Addressee acronym field. Only organizations with commonly used acronyms have a value in this field.

As noted in the description of the Addressee name field, the United States Department of Transportation Office of the Secretary and all DOT modal agencies are listed as acronyms in both the Addressee name and the Addressee acronym fields. For example, DOT, FAA, FHWA, FMCSA, FRA, FTA, and NHTSA. United States Coast Guard is also listed as an acronym (USCG) in both the Addressee name and the Addressee acronym fields.

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Addressee status

This field is only available in the ADVANCED SEARCH. It allows you to search on the addressee status of safety recommendations. In the Query value field, you choose from the list of all statuses. For single recipient recommendations, the overall status and the addressee status are the same. If there is more than one recommendation recipient, the addressee status can vary from the overall status​. The Condition options for Addressee status are is and is not.

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Date issued

This field is only available in the ADVANCED SEARCH. It refers to the date the safety recommendation was transmitted to the recipient. For date parameters enter a date using the month/day/year format. For example, 01/05/2005​.

To create a date range, make two rules. Choose the Condition is on or after and enter the first date in your range. Choose the Condition is on or before and enter the most recent date in your range. For example, for the date range January 1, 2016 through December 31, 2016, the parameters would be Condition is on or after 01/01/2015 and Condition is on or before 12/31/2016.

The Condition options for Date issued are is, is not, is after, is before, is on or after, and is on or before.

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Date overall closed

This field is only available in the ADVANCED SEARCH. This field refers to the date that the safety recommendation closed for its last recipient.

​​​For single-recipient recommendations, the overall date closed and the addressee date closed are the same. For multiple-recipient recommendations, the overall date closed and the addressee date closed can vary.

For date parameters enter a date using the month/day/year format. For example, 01/05/2005. To create a date range, make two rules. Choose the Condition is on or after and enter the first date in your range. Choose the Condition is on or before and enter the most recent date in your range. For example, for the date range January 1, 2016 through December 31, 2016, the parameters would be Condition is on or after 01/01/2015 and Conditionis on or before 12/31/2016.

The Condition options for Date overall closedare is, is not, is after, is before, is on or after, and is on or before.

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Date addressee closed

This field is only available in the ADVANCED SEARCH. This field refers to the date that a recommendation status was changed to closed for an individual recipient.

For single-recipient recommendations, the overall date closed and the addressee date closed are the same. For multiple-recipient recommendations, the overall date closed and the addressee date closed can vary. For date parameters enter a date using the month/day/year format. For example, 01/05/2005.

To create a date range, make two rules. Choose the Condition is on or after and enter the first date in your range. Choose the Condition is on or before and enter the most recent date in your range. For example, for the date range January 1, 2016 through December 31, 2016, the parameters would be Condition is on or after 01/01/2015 and Condition is on or before 12/31/2016.

The Condition options for Date addressee closed are is, is not, is after, is before, is on or after, and is on or before.

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Is reiterated

This field is only available in the ADVANCED SEARCH. This field refers to whether a safety recommendation has been reiterated or not. The Condition options for Is reiterated are is and is not. The Query value options are True and False.

​We reiterate recommendations when the safety issue addressed in the recommendation comes up again in a later investigation or study. Recommendations can be reiterated multiple times.

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Times reiterated

​This field is only available in ADVANCED SEARCH. This field refers to how many times a safety recommendation has been reiterated. The Condition options for Times reiterated are is, is not, is greater than, and is less than. The Query value box has up and down arrows allowing you to select a number. Safety recommendations cannot be reiterated a negative number of times.

We reiterate recommendations when the safety issue addressed in the recommendation comes up again in a later investigation or study. Recommendations can be reiterated multiple times. This fields returns items with an exact match. For example, selecting a Times reiterated value of 3 returns all recommendations reiterated exactly three times, not recommendations reiterated more than three times

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Field Descriptions – Safety recommendations- Other

Coding text

This field is only available in the ADVANCED SEARCH. It refers to the text of the taxonomy used to categorize safety recommendations. We are working on updating the recommendations to assign them the appropriate categorizations to facilitate the optimal use of this field. This field is not yet operational​.

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On Most Wanted List

This field is only available in the ADVANCED SEARCH. We associate related recommendations to each issue area on our Most Wanted List of Transportation Safety Improvements (MWL). The MWL represents the NTSB’s advocacy priorities and is designed to increase awareness of the most critical changes needed to reduce transportation accidents and save lives​.

This field allows you to search for SRs associated with the current MWL. The Query value options for the On Most Wanted List field are True and False. The Condition options are is and is not.

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Recommendation mode

This field is only available in the ADVANCED SEARCH. This field refers to the mode of the individual recommendation, which may differ from the investigation mode​.

​For example, the aviation office may investigate parasailing accidents, causing the investigation to be associated with the aviation mode. But, the recommendations that the aviation office issues may be marine recommendations. For these marine recommendations, issued by the aviation office, the recommendation mode is marine.

The first letter of the recommendation ID refers to the recommendation mode. A for aviation, H for Highway, I for intermodal, M for marine, P for pipeline, and R for rail. To search the recommendation mode, select from the list of choices in the Query value field. Intermodal recommendations are a unique category that may cross two or more modal areas; however, they will only be represented under intermodal. The Condition options are is and is not.

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Accident abstract text

Accident abstract text refers to the text of the abstract for the investigation or study which generated the recommendation​​. This field is only available in the ADVANCED SEARCH. You can choose the Condition contains, does not contain, is, is not, starts with, or ends with. In the ADVANCED SEARCH, multiple words entered in the Query value field must appear in sequential order in the Accident abstract text to appear as a query result.

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​Is multiple recipients

Accident abstract text refers to the text of the abstract for the investigation or study which generated the recommendation​​. The Condition options are is and is not. The Query value options are true and false. Some recommendations are issued to more than one recipient. These are known as multiple recipient recommendations. This search field allows you to search for whether a recommendation is a multiple recipient recommendation or not​.

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Priority level

This field is only available on the ADVANCED SEARCH. We occasionally designate safety recommendations as urgent, when they represent a pressing safety issue. We expect recipients to take action on urgent recommendations immediately. This field allows you to search for Urgent or Non-urgent recommendations in the Query value drop-down menu. The Condition options are is and is not.

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Is hazmat

This field is only available on the ADVANCED SEARCH. This field designates whether a recommendation concerns hazardous materials. Hazmat recommendations can be associated with any recommendation mode. The Query value options are True and False. The Condition options are is and is not.

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Is NPRM

This field is only available on the ADVANCED SEARCH. We monitor the Federal Register and comment on submissions from other federal agencies that concern transportation safety. Sometimes, our comments reference safety recommendations. If our comments reference recommendations, the comments are included in the recommendation database correspondence history and the recommendations are marked as being associated with an NPRM response. This field allows you to search for recommendations associated with our comments on other federal agencies’ Federal Register notices. The Query value options are True and False. The Condition options are is and is not.

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Recommendation Status

​​The status of a recommendation is "open" until the sufficient action has been achieved to mark it "closed". Please see the chart below for a list and explanation of all the recommendation statuses. Status determination is made periodically by the Board.

Status Assignment Definitions
Status
Status Definition
CEX
Closed--Exceeds Recommended Action:  Response by recipient indicates action on the safety recommendation has been completed. The action taken surpasses what the Safety Board envisioned.
CAA
Closed--Acceptable Action:  Response by recipient indicates action on the safety recommendation has been completed. The action complies with the safety recommendation.
CAAA
Closed--Acceptable Alternate Action:  Response by recipient indicates an alternate course of action has been completed that meets the objective of the safety recommendation.
CUA
Closed--Unacceptable Action:  Response by recipient expresses disagreement with the need outlined in the recommendation. There is no further evidence to offer, and the Safety Board concludes that further correspondence on, or discussion of, the matter would not change the recipient's position.  This status can also be used when the timeframe goals outlined in this order have not been met.
CUAN
Closed--Unacceptable Action/No Response Received:  No response to the recommendation was ever received.
CR
Closed--Reconsidered:  Recipient rejects the safety recommendation and supports this rejection with a rationale with which the Board concurs. Reasons for the "Reconsidered" status would include situations where the recipient is able to convince the Board that the proposed action would not be effective or that it might create other problems. This status is also assigned when the recipient of a recommendation was in compliance before the recommendation was issued or when the recipient was incorrectly chosen and cannot perform the recommended action.
CNLA
Closed--No Longer Applicable:  The recommended action has been overtaken by events.  For example, if technology and/or regulatory action has eliminated the reason for the recommendation or if a company has gone out of business.
CS
Closed--Superseded: Applied to recommendations held in an open status when a new, more appropriate safety recommendation is issued that includes the necessary elements of the recommendation to be closed.
CAAS, CAAAS, CUAS
Closed--Acceptable/Acceptable Alternate/Unacceptable Action Superseded: Applied to recommendations held in an open status when a new, more appropriate safety recommendation is issued that includes the necessary elements of the recommendation to be closed.  The Board determines the Acceptable/Acceptable Alternate/Unacceptable status based on the criteria defined above prior to superseding the recommendation.
OAA
Open--Acceptable Response:  Response by recipient indicates a planned action that would comply with the safety recommendation when completed.
OAAR
Open--Acceptable Alternate Response:  Response by recipient indicates an alternate plan or implementation program that would satisfy the objective of the safety recommendation when implemented.
OUA
Open--Unacceptable Response: Response by recipient expresses disagreement with the need outlined in the recommendation or attempts to convince the Board (unsuccessfully) that an alternative course of action is acceptable. The Board believes, however, that there is enough supporting evidence to ask the recipient to reconsider its position. This status can also be used when the Board believes that action is not being taken in a timely manner.
ORR
Open--Response Received:  Response has been received from recipient, but staff evaluation of the response has not been approved by the Board Members.
OAR
Open--Await Response:  When a safety recommendation is issued, the status "Open-Await Response" is automatically assigned.

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