In order to provide and accurate and reliable result, samples for the laboratory must be sent in accordance with guidelines to ensure they arrive in a fit condition to be analysed.
World Health Organisation Guidance (2005) states that: "Shippers of infectious substances must ensure that packages are prepared in such a manner that they arrive at their destination in good condition and present no hazard to others during transport."
Similarly, under various dangerous goods transport/carriage regulations (see below *), it is the responsibility of the consignor (sender/requester) to ensure that all dangerous goods, including diagnostic specimens, are correctly classified and packaged into suitable containers that are correctly marked and labelled.
* The various Carriage Regulations consist of the European Agreement concerning the International Carriage of Dangerous Goods by Road 2015 (ADR 2015), The Carriage of Dangerous Goods and Use of Transportable Pressure Equipment Regulations 2009 and The Carriage of Dangerous Goods and Use of Transportable Pressure Equipment (Amendment) Regulations 2009, as amended 2011.
It is therefore the responsibility of the requestor to ensure that all samples are sent to Viapath in accordance with the following instructions.
Potentially infectious samples from GPs transported by designated vehicles provided by Viapath or the local NHS Trust must be carried in compliance with the UK and European road transport regulations (*).
Infectious substances include material that is known to contain, or is reasonably expected to contain, pathogens. When being transported infectious substances must be packaged according to the UN standard P650 (Packing Instruction 650) as follows:
- All samples in containers (e.g. tube, pot known as the “primary”) must be placed in individual plastic ‘kangaroo’ type sample bags to avoid cross contamination. Where the primary contains a liquid, then the primary container must be leak proof. Where the primary contains a solid, then the primary container must be Sift proof (impermeable to dry contents).
- Individual sample bags should be placed into large, clear sealable, leak proof, plastic, sample bags (known as the “secondary”) that, where the specimen is a liquid, contains absorbent material sufficient to absorb the entire quantity of the liquid present in the specimen container (e.g. a sufficient amount of paper towelling to absorb any leakage).
- The large bag should be placed into a suitable rigid sample transport container that is capable of meeting the testing requirements of the regulations and that is correctly marked and labelled.
- Only rigid outer containers supplied by Viapath or the local NHS Trust may be used to transport samples to the laboratory by road.
- There should be sufficient cushioning lining the outer rigid container to prevent samples becoming unstable.
- If the rigid outer container becomes contaminated it must be disinfected by wiping out with 1000 ppm chlorine solution or equivalent.
- For more information on P650 see the guidelines here.
For more information on P 650 see the guidelines here.
Transport of samples in formalin
Formalin is covered by the Control of Substances Hazardous to Health Regulations 2002 (COSHH). Before formalin is used in the workplace, risk assessments under COSHH must be carried out to ensure that people are not exposed to formaldehyde vapour. Formaldehyde has a short term (15 minutes) workplace exposure limit of two parts per million per mg.m-3 and is a potential carcinogen.
Formalin spillage control granules should be available wherever formalin is used or stored and staff trained in their use. Granules are available here.
Advice on the safe use of formalin may be obtained from the local Viapath Histopathology department.
Samples for histology, and liquid based cytology, should be sent via designated vehicles organised by Viapath or the local NHS Trust as follows:
- Ensure the cap of the primary container is securely fastened.
- Wrap the primary container in absorbent material and place into a sample bag.
- Place the sample bag into a large plastic bag or cardboard box and place into the transport box. Ensure the sample remains upright in the transport box.
- The surgery must keep a log of all samples for Cytopathology and Histopathology sent to the laboratory. The patient’s name, type of sample and the date and time the sample was sent to the laboratory must be recorded, as well as the signature of the person who packaged and sent the sample.
- Under the Carriage Regulations, Formaldehyde solutions, non-flammable with less than 25% formaldehyde are not subject to the requirements of ADR.
- The Carriage Regulations permit the packaging 30ml or less of dangerous goods in the primary receptacle containing infectious substances with no additional requirements of the Carriage Regulations having to be met.
- As such, no additional special packaging is required there is no requirement for specialist marking & labeling of the package where it contains formalin. The P650 packaging, marking and labelling requirements must still be met.
Samples sent on dry ice
Samples on dry ice must not be sent in outer containers with a sealed lid as there is a risk of explosion during transport from the build up of carbon dioxide gas.
If dry ice is used to transport samples the outer packaging or over pack shall permit the release of carbon dioxide gas. The primary and the secondary packaging shall maintain their integrity at the temperature of the refrigerant used as well as the temperatures and the pressures which could result if refrigeration were lost. For more information see page 57 of the guidelines here.
When dry ice (solid carbon dioxide) is used as a coolant to keep specimens cold, the following requirements must be met:
- The dry ice must be placed outside the secondary packaging or in the outer packaging or an over pack.
- Interior supports must be provided to secure the secondary packaging in the original position after the ice or dry ice has dissipated.
- Packages containing dry ice for cooling shall be marked with the following wording on the outside of the package in addition to the P650 requirements:CARBON DIOXIDE, SOLID, AS COOLANT
- The markings shall be durable, legible and placed in such a location and of such a size relative to the package as to be readily visible.
Samples sent via Royal Mail
Packaging for samples sent via Royal Mail must also comply with P650 for Category B substances. P650 requires that the primary sample container must be leak-proof and wrapped in sufficient absorbent material to absorb any spillage (see information on sample packaging above). The primary container and absorbent material must be placed into a single sample bag with the request form in the pouch.
The sample bag should be placed into a suitable rigid container that is correctly marked and labelled. This product must be fully compliant with both Packing Instruction 650 and UN3373 requirements.
Labelling of packages
Packages containing infectious substances sent by post must be marked with:
- The sender’s name and address.
- The telephone number of a responsible person, with knowledge of the shipment.
- The receiver’s name and address.
- The proper shipping name Biological Substance, Category B”.
- The appropriate warning label for infectious substances should be used
- The outer packaging must always be suitably marked / labelled with the UN3373 contained within a diamond shape with minimum dimensions of 50 mm by 50 mm; the width of the line shall be at least 2 mm and the letters and numbers at least 6 mm high.
- The Proper shipping name “Biological Substance, Category B’’ must be marked on the outer packaging adjacent to the diamond shaped mark in letters at least 6 mm high.
- Labels shall be displayed on a background of contrasting colour, or shall have either a dotted or solid outer boundary line. The dotted outer boundary is not required when the label is applied on a background of contrasting colour
- The label must be affixed to the surface of the package and, if the dimensions allow, must be placed on the package so that it is not covered or obscured by any part or attachment to the packaging or any other label or marking. Where the package is of such an irregular size or small shape that the label cannot be satisfactorily affixed, the label may be attached to the package by a securely affixed tag or other suitable means.
- If the size of the package so requires, the dimensions of the labels may be reduced, provided that they remain clearly visible.
The HSE recommend the use of ‘high risk’ or ‘danger of infection’ stickers attached to samples and request forms from patients that pose a high risk of exposure to agents such as HIV, HBV, HCV, TB, Typhoid, Brucella, CJD. Care must be taken to protect the confidentiality of the patient when these stickers are used. See HSE Guidance Safe working and the prevention of infection in clinical laboratories and similar facilities ISBN 0-7176-2513-3.