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UK Civil Aviation Regulations

These are published by the CAA on our UK Regulations pages. EU Regulations and EASA Access Guides published by EASA no longer apply in the UK. Our website and publications are being reviewed to update all references. Any references to EU law and EASA Access guides should be disregarded and where applicable the equivalent UK versions referred to instead.



The following are the requirements for the medical certification of aircrew, including guidance material issued by the UK CAA Medical Department in relation to the haematology system.

MED.B.030 Haematology

Implementing Rules

  1. Applicants for a class 1 medical certificate shall be subjected to an haemoglobin test at each aero-medical examination.
  2. Applicants with a haematological condition may be assessed as fit subject to satisfactory aero-medical evaluation.
  3. Applicants for a class 1 medical certificate with any of the following haematological conditions shall be referred to the medical assessor of the licensing authority:
    1. abnormal haemoglobin, including, but not limited to anaemia, erythrocytosis or haemoglobinopathy;
    2. significant lymphatic enlargement;
    3. enlargement of the spleen;
    4. coagulation, haemorrhagic or thrombotic disorder;
    5. leukaemia.
  4. The fitness of applicants for a class 2 medical certificate with any of the haematological conditions specified in points (4) and (5) of point (c) shall be assessed in consultation with the medical assessor of the licensing authority
Close Implementing Rules

Acceptable Means of Compliance

CLASS 1 - AMC1 MED.B.030

(a) Abnormal haemoglobin
Applicants with abnormal haemoglobin should be investigated.

(b) Anaemia

(1) Applicants with anaemia demonstrated by a reduced haemoglobin level require investigation. Applicants with an haematocrit of less than 32 % should be assessed as unfit. A fit assessment may be considered in cases where the primary cause, such as iron or B12 deficiency, has been treated and the haemoglobin or haematocrit has stabilised at a satisfactory level.
(2) Applicants with anaemia which is unamenable to treatment should be assessed as unfit.

(c) Erythrocytosis
Applicants with erythrocytosis should be assessed as unfit. A fit assessment with an OML may be considered if investigation establishes that the condition is stable and no associated pathology is demonstrated.

(d) Haemoglobinopathy

(1) Applicants with a haemoglobinopathy should be assessed as unfit. A fit assessment may be considered where minor thalassaemia or other haemoglobinopathy is diagnosed without a history of crises and where full functional capability is demonstrated. The haemoglobin level should be satisfactory.
(2) Applicants with sickle cell disease (homozygote) should be assessed as unfit.

CLASS 2 - AMC2 MED.B.030

(a) Abnormal haemoglobin
Haemoglobin should be tested when clinically indicated.

(b) Anaemia
Applicants with anaemia demonstrated by a reduced haemoglobin level or low haematocrit may be assessed as fit once the primary cause has been treated and the haemoglobin or haematocrit has stabilised at a satisfactory level.

(c) Erythrocytosis
Applicants with erythrocytosis may be assessed as fit if the condition is stable and no associated pathology is demonstrated.

(d) Haemoglobinopathy
Applicants with a haemoglobinopathy may be assessed as fit if minor thalassaemia or other haemoglobinopathy is diagnosed without a history of crises and where full functional capability is demonstrated.

CLASS 1 - AMC1 MED.B.030

(h) Disorders of the lymphatic system

Applicants with significant localised and generalised enlargement of the lymphatic glands or haematological disease should be assessed as unfit and require investigation. A fit assessment may be considered in cases of an acute infectious process which is fully recovered or Hodgkin’s lymphoma or other lymphoid malignancy which has been treated and is in full remission.

CLASS 2 - AMC2 MED.B.030

(g) Disorders of the lymphatic system
Applicants with significant enlargement of the lymphatic glands or haematological disease may be assessed as fit if the condition is unlikely to interfere with the safe exercise of the privileges of the applicable licence(s). Applicants may be assessed as fit in cases of acute infectious process which is fully recovered or Hodgkin's lymphoma or other lymphoid malignancy which has been treated and is in full remission.

CLASS 1 - AMC1 MED.B.030

(j) Splenomegaly

Applicants with splenomegaly should be assessed as unfit and require investigation. A fit assessment may be considered when the enlargement is minimal, stable and no associated pathology is demonstrated, or if the enlargement is minimal and associated with another acceptable condition.

CLASS 2 - AMC2 MED.B.030

(i) Splenomegaly

Applicants with splenomegaly may be assessed as fit if the enlargement is minimal, stable and no associated pathology is demonstrated, or if the enlargement is minimal and associated with another acceptable condition.

CLASS 1 - AMC1 MED.B.030

(e) Coagulation disorders

(1) Applicants with a coagulation disorder should be assessed as unfit. A fit assessment may be considered if there is no history of significant bleeding episodes.
(2) Applicants with thrombocytopenia with a platelet count less than 75x109/L should be assessed as unfit. A fit assessment may be considered once the platelet count is above 75x109/L and stable.

(f) Haemorrhagic disorders

Applicants with a haemorrhagic disorder require investigation. A fit assessment with an OML may be considered if there is no history of significant bleeding.

(g) Thromboembolic disorders

(1) Applicants with a thrombotic disorder require investigation. A fit assessment may be considered when the applicant is asymptomatic and there is only minimal risk of secondary complication or recurrence.
(2) If anticoagulation is used as treatment, refer to AMC1 MED.B.010(g).
(3) Applicants with arterial embolus should be assessed as unfit. A fit assessment may be considered once recovery is complete, the applicant is asymptomatic, and there is only minimal risk of secondary complication or recurrence.

CLASS 2 - AMC2 MED.B.030

(e) Coagulation and haemorrhagic disorders

Applicants with a coagulation or haemorrhagic disorder may be assessed as fit if there is no likelihood of significant bleeding.

(f) Thromboembolic disorders

Applicants with a thrombotic disorder may be assessed as fit if there is minimal likelihood of significant clotting episodes. If anticoagulation is used as treatment, refer to AMC2 MED.B.010(g).

CLASS 1 - AMC1 MED.B.030

(i) Leukaemia

(1) Applicants with acute leukaemia should be assessed as unfit. Once in established remission, applicants may be assessed as fit.
(2) Applicants with chronic leukaemia should be assessed as unfit. After a period of demonstrated stability a fit assessment may be considered.
(3) Applicants with a history of leukaemia should have no history of central nervous system involvement and no continuing side-effects from treatment of flight safety importance. Haemoglobin and platelet levels should be satisfactory. Regular follow-up is required.

CLASS 2 - AMC2 MED.B.030

(h) Leukaemia

(1) Applicants with acute leukaemia may be assessed as fit once in established remission.
(2) Applicants with chronic leukaemia may be assessed as fit after a period of demonstrated stability.
(3) In cases (h)(1) and (h)(2), there should be no history of central nervous system involvement and no continuing side effects from treatment of flight safety importance. Haemoglobin and platelet levels should be satisfactory. Regular follow-up is required.

Close Acceptable Means of Compliance

Guidance Material

Applicants undergoing haemoglobin testing (Class 1 only)

Haemoglobin should be measured at every medical with appropriately maintained and calibrated testing equipment. Abnormalities on near patient testing should be confirmed with a full blood count assessed in a haematology laboratory. A certificate should not be issued until a satisfactory haemoglobin result is available.

Applicants undergoing bone marrow donation (Class 1, 2, 3 and LAPL)

Once applicants commence pre-donation treatment, a daily injection to increase the number of stem cells in their circulating blood, they should inform their aeromedical examiner (AME) and be assessed as unfit.

Treatment usually starts four days prior to the donation itself. Common side-effects of the pre-donation treatment are bone or muscle pain, nausea, headaches, and fatigue. Less commonly chest pain, insomnia, dizziness, and night sweats have been reported. Donation takes place on the fifth day and may need to be repeated on the sixth day if not enough cells were collected. Bone marrow is collected by one of two methods:

Peripheral blood stem-cell donation (PBSC)

Stem cells are collected from the circulating blood. No anaesthetic is required. If the applicant feels fully recovered after 48 hours they should contact their AME for a fitness assessment to return to operational duties. If there is any doubt about fitness the AME may request a report regarding any side-effects or complications.

Bone marrow aspiration

A syringe is used to aspirate bone marrow from the hip bone and this procedure is usually performed under a local anaesthetic as a day case. If the applicant feels fully recovered after 48 hours, they should contact their AME for a fitness assessment to return to operational duties.

Guidance on blood donation

There is a small risk of fainting or syncope following donation. Donating blood or plasma should be avoided during the 24 hours before duty for holders of Class 1, 2 and LAPL medical certificates, and during the 12 hours before duty for holders of Class 3 medical certificates.

Applicants with abnormal haemoglobin results including anaemia (Class 1, 2, 3 and LAPL)

Applicants should be assessed as follows:

Lower limit

For values below 13g/dL (men) and 12g/dL (non-pregnant women), all applicants should undergo further review to determine the cause of anaemia. These figures are based upon the WHO values for diagnosis of anaemia. A value below 11.5g/dL (men) and 10.5g/dL (women) should result in an unfit assessment whilst this is undertaken.

The relative hypoxia encountered at altitude may exacerbate anaemia symptoms which are compensated for at sea level. These can include fatigue, reduced exercise tolerance or palpitations. An applicant should therefore be unfit whilst undergoing investigation. Applicants with longstanding chronic anaemia caused by thalassaemia trait are exempt from this requirement.

Upper limit

Above 18g/dL (men and women) should undergo clinical review for polycythaemia. Potential symptoms of hyper-viscosity including blurred vision, headaches and fatigue, as well as an increased risk of thrombosis, mean an unfit assessment should be considered whilst this occurs.

Once anaemia is corrected and an applicant is stable on appropriate therapy (when required) they may be assessed as fit.

Applicants with erythrocytosis including haemochromatosis (Class 1, 2 and 3)

An applicant with a diagnosis of erythrocytosis including polycythaemia, haemochromatosis or other iron overload state should be assessed as unfit. A cardiology assessment is required following diagnosis to include an echocardiogram, Holter and exercise ECG. Historic investigations undertaken after diagnosis may be acceptable for this purpose.

Applicants should not exercise the privileges of their licence within 24 hours of having venesection as treatment. Applicants should have a satisfactory serum ferritin and haematocrit following treatment. Follow up haematology reports are required on at least an annual basis. Provided ferritin and haematocrit remain satisfactory, subsequent cardiology review is not always necessary.

Haemochromatosis

Unrestricted medical certification can be considered for applicants (both homozygotes and heterozygotes) by a Civil Aviation Authority (CAA) medical assessor (Class 1 and 3) or AME (Class 2), provided iron levels are satisfactorily controlled and upon on receipt of acceptable cardiology and haematology medical reports. Any evidence of iron overloading or complications including cirrhosis, arthropathy, diabetes or cardiomyopathy should be referred to a CAA medical assessor.

Polycythaemia

Secondary causes should be investigated as appropriate. Class 1 and 3 applicants should be referred to a CAA medical assessor once haematocrit is normalised and with a haematology report which includes a prognosis and/or likelihood of transformation to acute myeloid leukaemia.

Applicants with haemoglobinopathies (Class 1, 2 and 3)

Sickle cell trait

Applicants may be assessed fit for unrestricted certification of all classes.

Sickle cell homozygotes

Individuals can suffer painful ‘crises’ upon exposure to hypoxia, cold and dehydration. The likelihood of incapacitation precludes certification of any class.

Thalassaemia trait

Applicants may be assessed as acceptable for unrestricted certification subject to the receipt of a haematology report. Haemoglobin should be greater than or equal to 9g/dL.

Aspirin and clopidogrel are acceptable anti-platelet medications.

Anagrelide inhibits platelet formation. Applicants requiring this medication should be assessed as unfit. Medical certification can be considered for applicants by a CAA medical assessor (Class 1 and 3) or AME (Class 2) no sooner than 2 weeks after commencing this treatment, subject to a satisfactory haematology report to include comment on any side-effects. Thrombocytosis requires referral to a CAA medical assessor.

Applicants with coagulation or haemorrhagic disorders (Class 1, 2 and 3)

Thrombocytopaenia

Applicants with a diagnosis of thrombocytopenia should be assessed as unfit. Medical certification is considered subject to a haematology report acceptable to a CAA medical assessor (Class 1 and 3) or AME (Class 2). Platelet counts below 75 x 109/L should be assessed as unfit. Following investigation, a fit assessment may be considered once the platelet count is above 75x109/L and stable.

Haemophilia

Applicants with a diagnosis of haemophilia A (factor VIII deficient) or haemophilia B (factor IX deficient, Christmas disease) should be assessed as unfit. Medical certification is considered for applicants with a diagnosis of mild forms with >15% coagulation factor subject to a haematology report acceptable to a CAA medical assessor (Class 1 and 3) or AME (Class 2). A history of spontaneous bleeding is not acceptable for medical certification.

Von Willebrand disease

Applicants with a diagnosis of Von Willebrand disease should be assessed as unfit. Medical certification is considered subject to a haematology report acceptable to a CAA medical assessor (Class 1 and 3) or AME (Class 2) confirming that the phenotype is mild, that there is no history of significant bleeding, and that therapy is not required.

Applicants with disorders of the lymphatic system (Class 1, 2 and 3)

Lymphoedema

Class 1 & 2 applicants may need to provide a medical flight test to confirm no significant functional impairment from limb swelling.

Lymphadenopathy

Applicants with significant persisting lymphadenopathy must be made unfit whilst undergoing further investigation.

Lymphoma

Guidance material currently under review.

There is additional guidance on pulmonary embolism and deep vein thrombosis.

Close Guidance Material