AC 125-1A

Advisory circular · Operations of Large Airplanes Subject to 14 CFR Part 125

Approved
September 15, 2016
Last reviewed
August 29, 2024
Cancels
AC125-1
Family
AC 125-1 · 2 versions
Revision
A
14 CFR parts
43, 61, 65, 91, 119, 121, 125, 135, 145

Guidance, not mandatory unless a rule or AD requires it. DRS record last changed November 21, 2025.

Show pages 16–27

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4.8.8 Corrective Action Notification. After resolving any discrepancies with any of the documents or the inspections, the applicant must notify the CPM, in writing, detailing the corrective action taken. The demonstration and inspection phase should then be continued.

4.9 The Certification Phase.

4.9.1 Issued Certificates and OpSpecs. In the Certification Phase, the certificate and approved OpSpecs are issued after all unsatisfactory items are corrected. No certificate shall be issued until the team determines the applicant is fully capable of fulfilling responsibilities as charged by Title 49 of the United States Code (49 U.S.C.).

4.9.2 OpSpecs Review. The CMT will review the OpSpecs to determine that they:

1. Contain adequate provisions to meet all items listed in § 125.31(b).

2. Contain any other provisions applicable to your operations.

3. Do not contain information that is contrary to the applicable CFRs.

4. Contain reference to any deviations authorized.

4.9.3 Certificate Issuance. A certificate is issued to the applicant when the following criteria are met:

1. The certification process is completed.

2. Each unsatisfactory item has been corrected.

3. It is determined that the applicant has met all regulatory requirements and understands all responsibilities under the regulations.

4. It has been determined the applicant is capable of complying with the part 125 on a continuing basis.

5. The applicant’s ability to conduct operations in a safe manner has been demonstrated.

4.9.4 Amended Certificates. If a certificate is amended to reflect an address change or a change of the assigned district office, the date of original issuance shall be shown on the new certificate.

4.9.5 Legal Name Changes. A change of official name must be approached with care.

Whatever the complexity of the legal name change, it has the effect of a new certification; therefore, a new certificate and certificate number shall be issued. For this situation the issuance date of the new certificate will be entered in the space provided on the certificate.

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4.10 Designation of a Check Airman.

4.10.1 Check Airman Qualifying Evaluations. If you request approval of a check airman and the FAA finds that this approval is warranted by operational factors and your nominee is acceptable, he/she must complete the qualifying evaluations.

4.10.2 Instrument Proficiency Test. He/she must complete the instrument proficiency test provided in § 125.291. He/she will conduct flight test(s) of other company flightcrew members while being observed by an FAA inspector. Assuming he/she successfully completes these tests, the company will be issued a letter of authorization (LOA) authorizing the use of a check airman.

Note: Further information regarding check airmen is contained in Chapter 3 and Chapter 8.

4.11 Testing of Crewmembers.

4.11.1 Records Review. The check airman or FAA inspector conducting the crewmember testing will review the company records required by § 125.401 for these crewmembers.

The flightcrew members will be requested to present their airman and medical certificates and logbooks for review.

4.11.2 Initial and Recurrent Pilot Testing. All pilot crewmembers must successfully complete the 12-month test required by § 125.287 before they can serve as a pilot. An FAA Form 8410-1, Airman Proficiency/Qualification Check, will be used to document the results of that test. A copy of the completed form should be maintained in the company records.

4.11.3 Electronic Testing System (ETS). An ETS may be used to satisfy the requirements of § 125.287(a)(1), with the exception that testing on OpSpecs and the manual of the certificate holder is a specific testing requirement for each individual operator and may not be applicable to a generic ETS system. If an ETS system is used to test OpSpecs and the manual of an individual operator, it must be applicable to the specific operator and cannot be used until approved by the principal operations inspector (POI). In addition, § 125.287(a)(4) through (9) may use an ETS system to satisfy the testing requirements, but must be approved by the POI prior to use. Minimum testing requirements using an ETS system will be established by the operator and approved by the POI. A minimum passing score of 70 percent corrected to 100 percent is recommended.

4.11.4 Instrument Proficiency Check (IPC). Pilots who will serve as a pilot in command (PIC) must successfully complete the IPC required by § 125.291. A letter of competency will be issued following the successful completion of the IPC. A copy of this document should be maintained in the company records.

4.11.5 Flight Attendant (F/A) Testing. The certificate holder is responsible for the testing of an F/A’s knowledge and competency per § 125.289.

Note: Further information regarding crewmember qualification is provided in Chapter 8.

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4.12 Maintenance Considerations.

4.12.1 Part 125 Certificate Holders. The holder of a part 125 operating certificate is not authorized under that certificate to accomplish maintenance or return the airplane to service after maintenance. This does not preclude a certificate holder from employing certificated mechanics who can perform these functions on the authority of their certificates or providing the facilities necessary for the accomplishment of the maintenance. A part 125 certificate holder may also hold a certificate under 14 CFR part 145 for a repair station. In this case, airplane maintenance and return to service may be accomplished under the authority of the part 145 certificate holders, provided the repair station holds the appropriate ratings. Under part 125, the certificate holder is able to provide for maintenance through one of these methods, it will be necessary to provide for scheduled and/or routine maintenance through agreements with other organizations which have the appropriate authority and ratings to accomplish the maintenance.

4.12.2 Agreements and Provisions for Maintenance. During the certification process, the FAA will review your agreements with other organizations for maintenance, and any other provisions you have made for the accomplishment of maintenance, to assure that you have provided for all aspects of scheduled and unscheduled maintenance. If you have elected to provide the facilities for the maintenance of your airplanes, these facilities and the authority which will be used to perform the maintenance and return the airplane to service will be subject to review and inspection. All aspects of the facilities and personnel will be evaluated regarding understanding of your manual, personnel qualifications, experience, equipment, and the overall ability of the facility to produce a properly inspected and maintained airplane. This will also be true in respect to avionics functions.

Note: Additional information on airplane inspection programs is found in Chapter 9.

4.13 Issuance of Operating Certificate.

4.13.1 Successful Completion of Tests/Inspections. You will be issued a part 125 operating certificate upon successful completion of the tests and inspections discussed in this chapter (refer to § 125.27(a)).

4.13.2 Certificate Display. A copy of the certificate must be displayed in each airplane used for part 125 operations (refer to § 125.7(a)).

4.14 Approval of OpSpecs. The applicable OpSpecs will be processed in the FAA’s Web-based Operations Safety System (WebOPSS) and electronically signed by the operator, if the operator has made provisions for WebOPSS electronic signature, and the principal inspector (PI). If the operator does not have WebOPSS electronic signature authority then the designated company representative will hand sign each applicable OpSpecs. You should retain the original at your principal base of operations, and place a copy in your company’s PPM.

4.15 Final Certification. Upon receipt of the operating certificate, approved OpSpecs, and accepted company manual, certification is complete. You are now a part 125 certificate holder.

5-1 CHAPTER 5. FAA SURVEILLANCE AFTER CERTIFICATION

5.1 Scope and Contents. This chapter explains surveillance that the FAA conducts on 14 CFR part 125 certificate holders. The listed inspections are not an exhaustive list, but outline the major inspections you can expect as a part 125 certificate holder. Inspectors are authorized to conduct other inspections, as necessary, to ensure the operator is in compliance with the Federal aviation regulations, applicable to their operation.

5.2 Inspection Authority.

5.2.1 Administrator Authority. Part 125, § 125.45 states that each certificate holder shall allow the Administrator, at any time or place, to make any inspections or tests to determine an operator’s compliance with the Federal Aviation Act of 1958, the Federal Aviation Regulations, its operating certificate and operations specifications (OpSpecs), its Letter of Deviation Authority (LODA), or its eligibility to continue to hold its certificate or LODA.

5.2.2 Types of Inspections. In the course of exercising this inspection authority, FAA inspectors (operations and airworthiness) conduct facility (base) inspections, ramp inspections, airplane inspections, en route inspections, and other related surveillance.

5.3 Identification of Inspectors. All FAA inspectors authorized to conduct inspections have an inspector credential (FAA Form 110A, Aviation Safety Inspector’s Credential) which identifies them as an inspector. The certificate holder’s personnel may request to see this credential when approached by any aviation safety inspector (ASI) when that inspector is present to conduct any authorized inspection.

5.4 Facility (Base) Inspections. These inspections are conducted on a recurring basis to ascertain that the certificate holder’s facilities continue to meet the original certification standards.

5.5 Ramp Inspections. The FAA conducts announced or unannounced surveillance of airplanes which have just completed, or are about to engage in, flight operations. The major items reviewed in these inspections include, but are not limited to: flightcrew certification, flight and duty time limitations, instrument and equipment requirements, Weight and Balance (W&B) limitations and procedures, minimum equipment list (MEL) procedures (as applicable), flight locating requirements, or any other issues that may affect the safety of the flight.

5.6 En Route Inspections.

5.6.1 Flight Deck Inspection. During an en route inspection, the FAA inspector will ride on the flight deck and observe and evaluate crew performance during a part 125 operation.

Inspectors are authorized to make this inspection, on an announced or unannounced basis, provided they identify themselves by presenting their credentials and a copy of a completed FAA Form 8430-13, Request for Access to Aircraft, to the certificate holder or his/her representative (i.e., pilot in command (PIC)).

5-2 Note: In addition to a flight deck inspection, an FAA inspector may conduct a cabin en route inspection to verify that the cabin crew adheres to all applicable regulations and the applicable company policies and procedures.

5.6.2 Access to Flight Deck. Certificate holders should make their flightcrews aware of the requirements of §§ 125.315 and 125.317. An ASI who presents the proper credentials must be allowed free and uninterrupted access to the pilot compartment of the airplane.

Failure to allow this access, except in cases involving the invoking of the emergency authority of the PIC, may result in enforcement action against the pilot and/or certificate holder.

5.6.3 Inspection Briefing. Inspectors should brief the PIC of their findings at the termination of the flight and, as necessary, advise company management personnel.

5.7 Airplane Inspections. FAA airworthiness inspectors will conduct scheduled or nonscheduled inspections of airplanes operated under part 125 on a regular basis to determine that the airplanes continues to meet the original standards for certification.

5.8 Simulator Surveillance. FAA inspectors will conduct periodic surveillance of simulators and flight training devices (FTD), to ensure they meet the requirements of §§ 125.296 and 125.297. Principal operations inspectors (POI) may utilize the Training Center Program Manager (TCPM) to assist him/her in the surveillance of simulators used by a part 125 operator.

5.9 Check Pilot Surveillance. POIs are responsible for providing surveillance over all individuals assigned as check pilots/contract check pilots for their assigned air operators.

POIs will observe authorized check airmen conduct oral and flight tests, on an annual basis, to assure that applicable standards and procedures are being used. Contract check airman employed by an approved 14 CFR part 142 training center will be observed every 24 calendar-months. With regard to authorized contract check airman employed by approved part 142 training centers, the POI may ask TCPMs to assist them in the observation of contract check pilots assigned to their air operators.

5.10 Additional Information. Additional information can be found at the FAA’s Web site at http://fsims.faa.gov.

6-1 CHAPTER 6. OPERATIONAL CHANGES

6.1 Scope and Contents. This chapter outlines changes to your operation which will require that you inform, or receive the approval of, the FAA prior to implementation.

6.2 Change of Ownership.

6.2.1 Certificate Transfer. A 14 CFR part 125 operating certificate cannot be transferred from one person to another. Upon change of ownership, the FAA will suspend the operating certificate under the provisions of part 125, § 125.29. A determination will be made that the new owner’s operation meets the certification requirements of part 125.

6.2.2 Coordination Prior to Ownership Change. Purchasers of a company holding a part 125 operating certificate may avoid having the company’s operations interrupted through coordination with the Flight Standards District Office (FSDO) that issued the certificate prior to the transfer of ownership.

6.2.3 Certification Process and Requirements. The new purchaser may not have to complete all steps of the certification process if the FAA determines that no significant changes to the basis for original certification of the company or its operations under part 125 will occur as a result of the transfer of ownership. However, the jurisdictional FSDO may require the new owner to meet some or all of the requirements for a new certification, depending on the degree of change that occurs within the company as a result of new ownership. If significant changes occur as the result of a change of ownership, the jurisdictional FSDO will decide, based on those changes, what steps of the certification process will have to be completed by the new owners prior to part 125 operations.

6.3 Voluntary Surrender of Certificate and Operations Specifications (OpSpecs).

6.3.1 Cancellation Requests. Certificates and OpSpecs which are voluntarily surrendered for cancellation should be accepted. The certificate must be accompanied by a written request from the operator stating the reason for cancellation. The request must be signed by either a person authorized to act for the company, or by the owner. This request may not be conditional.

6.3.2 Lost or Destroyed Certificates and OpSpecs. If the operating certificate or OpSpecs have been lost or destroyed, a statement by the certificate holder to this effect should be included in the written request for cancellation.

6.4 Change of Business Name or Address.

6.4.1 Amendment Application. A part 125 operator may apply to amend either the operating certificate or the OpSpecs. The FAA may also amend the operating certificate or the OpSpec as the result of actions taken under Title 49 of the United States Code (49 U.S.C.) § 44709 and 14 CFR part 13.

6.4.2 Applications for Name or Address Changes. If the certificate holder wishes to change the legal name on a certificate or change the address of its principal business office or its

6-2 principal operations base, the operator must apply to amend the existing operating certificate. The application will be in letter form to the certificate-holding district office (CHDO). All supporting documents should accompany the request for amendment.

Note: Address changes of the principal business office, operations base and/or maintenance base must be reported, in writing, to the FAA district office, at least 30 calendar-days in advance of the change (refer to § 125.47). This change may necessitate an inspection by district office personnel to assure that the new facilities meet the requirements of part 125.

6.4.3 Reissued Certificates. The certificate will be reissued with the proper changes; will keep the original date of issuance, and will show the amended date of issuance.

6.4.4 Amendment Authority and Requirements. Section 125.35 provides the authority and requirements for the amendment of OpSpecs.

6.5 Change of Management Personnel.

6.5.1 Notification of Management Change. The certificate holder is required to notify the jurisdictional FSDO of any change in management personnel assignments within 10 calendar-days (refer to § 125.25(c)). These changes will be reviewed to determine that any new personnel have not been previously employed in any of the situations described in § 125.27(b)(2).

6.5.2 Required Documents. The notification, to the jurisdictional FSDO, should be made by letter and accompanied by a proposed revision to the Policy and Procedures Manual (PPM). The applicable OpSpecs must be updated with the management personnel changes.

6.6 Amendments to OpSpecs.

6.6.1 Amendment Initiation. It may, at times, become necessary to amend your OpSpecs due to changes in equipment, personnel, or facilities. The amendments may be initiated by you or the FAA.

6.6.2 Amendment Requests. An operator may, in accordance with 14 CFR part 119, § 119.51, apply for an amendment to its OpSpecs by submitting a request in writing to the appropriate FAA office. The certificate holder or operator’s request should include: a formal request for the desired changes, an explanation of the reasons for those changes, and any supporting information. In accordance with § 119.51, the certificate holder or operator must file the application for amendment at least 15 calendar-days (the FSDO may agree to a shorter period) before the proposed effective date of the amendment.

6.6.2.1 If the application is incomplete the FAA should inform the applicant that the application is not acceptable in its present form but will be considered upon the receipt of additional, specified supporting documents and/or information.

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6.6.2.2 The FAA may determine that the application is not acceptable, because the certificate holder or operator’s request does not provide for an adequate level of safety in air transportation or air commerce; it would not be in the best interest of the public; or it is in conflict with FAA policy or 14 CFR. In such a case, the applicant should be informed, in writing, that the application is unacceptable and include a statement explaining why it is not acceptable.

6.6.3 Accepted Amendments. If the FAA determines that an amendment to the certificate holder or operator’s OpSpecs is justified, the FAA should amend the OpSpecs. In the case of a change in a certificate holder or operator’s operating environment or when the FAA has specific safety concerns, the following procedures apply:

6.6.3.1 In some cases the FAA may decide to amend a certificate holder or operator’s OpSpecs due to a change in the operator’s operational environment. For example, the FAA may create a new OpSpecs paragraph to ensure uniform compliance with a certain aspect of 14 CFR. In such cases, the principal operations inspector (POI) may initiate and amend an operator’s OpSpecs due to the change, without the operator having to apply for the change. Once the operator has demonstrated compliance with all appropriate parts of 14 CFR and operational and airworthiness requirements, the OpSpecs may be issued.

6.6.3.2 Section 119.51 provides the authority for the FAA to unilaterally amend a certificate holder or operator’s OpSpecs when the FAA has determined that safety in air commerce and the public interest necessitates such an amendment. When amending a certificate holder or operator’s OpSpecs, the FAA is required to notify the certificate holder or operator in writing and then allow a minimum of 7 calendar-days for comments regarding the proposal.

The 7-calendar-day period provides the certificate holder or operator with an opportunity to submit written information, views, and arguments on the proposal. After reviewing the comments, the FAA either rescinds or adopts the amendment. If the FAA decides to amend the OpSpecs, the final amended OpSpecs should have an effective date of not less than 30 calendar-days after receipt by the operator. Examples of the types of FAA-initiated amendments due to safety concerns are as follows:

6.6.3.2.1 The FAA will propose to amend a certificate holder or operator’s OpSpecs when it has determined that the certificate holder or operator’s operating environment or its operational capability is no longer consistent with the operating authorizations, conditions, and limitations contained in its OpSpecs.

Examples of such cases are when the certificate holder or operator:

1. Terminates operations with a specific make/model/series (M/M/S) of airplane that is authorized in its OpSpecs.

2. Has a series of accidents or incidents involving a particular type of operation (such as low visibility takeoffs and/or landings at a time when the OpSpecs authorize lower than standard weather minimums).

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3. Terminates a particular type or kind of operation or Area of Operation (such as when the operator no longer conducts North Atlantic High Level Airspace (NAT HLA) operations).

6.6.3.2.2 The FAA also amends a certificate holder or operator’s OpSpecs when the standard automated OpSpecs have been revised on a national basis and Washington headquarters (HQ) has requested that PIs amend all, or some of their operator’s OpSpecs. In this case, the OpSpecs should be amended in accordance with guidelines and procedures that have been established by Washington HQ.

6.7 Certificate Holder or Operator Appeal Rights.

6.7.1 OpSpec Amendment Appeal Rights. In all situations involving OpSpec amendments or FAA-initiated, non-emergency amendments, a certificate holder or operator has certain appeal rights. These appeal rights are provided in § 119.51, and are exercised according to the way in which the amendment was initiated, as follows:

6.7.1.1 If the FAA has determined that a certificate holder or operator’s request for an amendment to its OpSpecs is unacceptable, the operator may, within 30 calendar-days after receipt of the CHDO’s notice of disapproval, petition the Director of Flight Standards Service (AFS-1) to reconsider the CHDO’s refusal to amend the OpSpecs.

6.7.1.2 During the course of the reconsideration time period, no amendments to the OpSpec paragraph(s) will be made. A petition made by a certificate holder or operator more than 30 calendar-days after receiving the notice of disapproval will not be considered by FAA. If AFS-1 determines that an amendment to a certificate holder or operator’s OpSpecs is justified, the appropriate regional Flight Standards division (RFSD) office will be notified and instructed to amend the OpSpecs either as requested by the certificate holder or operator or as amended by FAA. If AFS-1 determines, after considering the certificate holder or operator’s petition, that an amendment is not appropriate, the operator and the RFSD will be notified accordingly.

Note: If AFS-1 denies the appeal, 14 CFR does not provide any additional appeal rights for the operator.

6.8 Surrender of OpSpecs.

6.8.1 Operating Environment Changes. Upon a change in its operating environment, a certificate holder or operator should relinquish the appropriate paragraphs of its OpSpecs for which it no longer meets the requirements of the authorization. If the certificate holder ceases operations, it must surrender its operating certificate and all its OpSpecs.

PIs are responsible for updating the Web-based Operations Safety System (WebOPSS) of the certificate holder or operator’s certificate status and date of change in the operating environment in WebOPSS, as applicable.

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6.8.2 OpSpecs Authorization Criteria. Criteria to hold a particular OpSpecs authorization is no less than that necessary for its original issuance. For example, if a certificate holder or operator was issued an authorization to conduct operations in areas of magnetic unreliability (AMU) airspace, but no longer has airplanes equipped to conduct that kind of operation, the certificate holder or operator must surrender the AMU authorization. In addition, the following situations also apply:

6.8.2.1 If a certificate holder or operator ceases all operations and is no longer equipped, or able to conduct any kind of operation, the CHDO shall request that the certificate holder or operator voluntarily surrender all of the OpSpecs associated with the secession of operations associated with the specific OpSpecs. Depending upon the circumstances, the CHDO may also request that the certificate holder or operator voluntarily surrender their operating certificate.

6.8.2.2 If an operator operates seasonally and is equipped to resume operations during the appropriate season, that operator is not required to surrender OpSpecs during their inactive season.

6.8.2.3 If an operator does not meet the requirement to hold an OpSpec paragraph, but refuses to surrender the paragraph, the POI shall amend the OpSpec as discussed in paragraph 6.6. If safety in air commerce is affected, then an emergency amendment is appropriate.

6.8.2.4 If a certificate holder or operator voluntarily surrenders a part of its OpSpecs, the principal inspector (PI) must archive the affected OpSpecs in WebOPSS and reissue A004, Summary of Special Authorizations and Limitations. If a certificate holder or operator surrenders its operating certificate, the PI must change the certificate status to “Voluntary Surrender” by editing the operator details in WebOPSS.

6.9 Revisions to Company Manuals.

6.9.1 Revising Policies and Procedures. You may amend your manuals and incorporate new or revised policies and procedures. When making these revisions, you should:

1. Assure that they comply with the applicable provisions of the CFR.

2. Submit the revision to the FAA district office for acceptance or approval prior to the planned implementation.

6.9.2 Revisions for Safety and CFR Compliance. The FAA may request a revision to any part of the manual when such revision is in the interest of safety, or when the manual does not meet the requirements of the applicable CFR.

6.9.3 Proposal Submission. Proposed amendments/revisions should be submitted to the FAA district offices for acceptance or approval normally 60 calendar-days prior to the operator’s intended use. The proposal will be handled in the same manner as the original

6-6 manual. If the revision/amendment is to a portion of the manual which must be approved

(i.e., the airplane inspection program, refer to § 125.73(n)), the procedures may not be incorporated in the manual for use until approval has been granted.

6.9.4 Currency of Manual. It should be noted that you are required to keep your manual current (refer to § 125.71(a)). Thus, if you change procedures and do not revise or amend your manual prior to initiating the procedures, you have not acted in accordance with part 125.

6.10 Changes to Your Airplane Fleet.

6.10.1 Added or Removed Airplanes. The addition or deletion of airplanes from your fleet will require changes to your OpSpecs.

6.10.2 Different Make and Type or Model Airplane. Additions of a different make and type or model of airplane to your fleet may also result in a requirement for:

1. Crewmember testing (refer to §§ 125.287 and 125.289).

2. Revisions to your inspection program (refer to §§ 125.71(a) and 125.73(n)).

3. An emergency evacuation demonstration (refer to § 125.189 and part 125 appendix B).

6.10.3 Operation of New Airplane. A new airplane, added to your fleet, may not be operated under part 125 until the above requirements, and any other applicable requirements, are met.

6.11 Changes to Airplane Passenger Capacity or Interior Configuration. An emergency evacuation demonstration will be necessary if you increase the passenger capacity, of your airplane, by more than 5 percent or make a major change to the interior configuration that will affect the emergency evacuation of passengers. This demonstration must be completed satisfactorily before the airplane is operated under part 125 (refer to § 125.189(a)(2)).

6.12 Revisions to Minimum Equipment Lists (MEL). If you want to change your approved MEL, you should:

1. Notify and consult with the FSDO regarding your proposed revision.

2. Modify only those pages which will contain the revised portions.

3. Submit your proposed revision(s) to the FSDO.

4. Not use the proposed revision, or insert it into any document used by flightcrew members, until it is approved by the FSDO.

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6.13 Disposition of OpSpecs.

6.13.1 Principal Operations Base. A copy of the OpSpecs must be maintained at the principal operations base (refer to § 125.41).

6.13.2 Company Manual. You can include your OpSpecs in your manual or pertinent excerpts of your OpSpecs. If you elect to include only pertinent excerpts in your manual, they must be referenced in your manual in such a manner that they (the OpSpecs) retain their identity as OpSpecs (refer to § 125.43(b)). In addition when OpSpecs information is incorporated into your manual, the text will clearly identify each excerpt as part of the OpSpec and state that compliance with each OpSpec is mandatory.

Note: You can include your entire OpSpecs as a separate section in your manual, and reference pertinent excerpts of your OpSpecs, in the appropriate sections of your manual, at your discretion.

6.13.3 Employees. Each employee will be informed of the provisions of the OpSpecs that apply to his/her duties and responsibilities (refer to § 125.43(a)).