Random testing has increasingly become a fact of life since the suspension and subsequent ban of Olympic sprint champion Ben Johnson in 1988. Samples are collected by individuals who have been trained in accordance with standard guidelines decreed in the IOC's Certification of International Doping Control Officers.
In Michelle de Bruin's case, the principal officer in her random testing of January 8th was Al Guy, an Irish official with eight years of dope testing experience, on behalf of International Doping Tests and Management, the world's leading agency for testing.
Having called to the address at which the testers have been told the athlete will be present, they will wait for a period of up to two hours after the time of arrival.
The athletes are given as much as two hours to complete any activity they may be engaged in. During this time they must be in continuous view of the testers.
The tester carries a transportation case containing two matching bottles to be marked A and B, both of which will have a code permanently marked on them to ensure they correspond. Tamper-evident tape, certified to be sanitised and drug-free, must be carried for sealing the bottles. Desiccant packets - little packets of a drying agent - in specimen bottles and containers, and absorbent material, must be present for transportation of urine.
When providing the sample, the athlete must be supervised by a tester of the same gender. A minimum of 75 ml of urine must be provided.
In the presence of the athlete, the specific gravity (extent to which it is diluted) and Ph (acid base balance) of the urine is measured using a residual volume in the collecting vessel. Guidelines suggest a specific gravity exceeding 1.01 or higher is desirable, or the test must be retaken. Ph should not exceed 7.5.
The athlete then chooses two bottles from hermetically sealed containers. One is marked "A" and becomes the main sample. The other, marked "B", becomes the reserve sample. Sample A must contain a minimum of 40 ml of urine.
The bottles are sealed and the athlete ensures that the code on each bottle is the same as the code entered by the officer on the doping control form.
Signatures of the athlete, the officer and at least one accompanying official must appear on the form, confirming that the procedures were carried out as above. Test details and athlete details are filled out on this form, including time of test, sex and name of athlete, volume of urine collected, test code and bottle code numbers, and declarations of any medications taken by athlete in preceding three days. The athlete is permitted to make comments on the procedure.
The samples are then stored in special Envopak or Versapak zip-locked containers which comprise glass bottles in casing. These must have an integrity seal to ensure they were never previously used.
If the officer believes there were suspicious circumstances surrounding the taking of the sample, he may ask for another sample.
Once complete, the package is wrapped in tamper-evident security seals and another system-coded sealing system with an identifiable code number.
All samples are sent immediately to an accredited laboratory - there are 20 worldwide. A chain of custody document is used to record the contents and custody of the equipment from the site of collection to the lab. All equipment and samples must be received by the lab sealed with the seal of the collecting agency.
Analysis is geared towards detecting the presence of anabolic agents, diuretics, peptide hormones and glycoprotein hormones. Analysis of the A sample is carried out as soon as possible after arrival, while the B sample is stored in a locked refrigerator.
Analysis is carried out on a variety of equipment - principally, gas chromatographs and mass spectrometers which perform the basic screening for stimulants and narcotics.
Small amounts of the sample are measured into four test tubes, which undergo a chemical work-up so that it will be pure enough to inject into the instruments. The urine is dripped slowly through a resin which catches steroids but allows water, salt and other chemicals to pass through. The steroids are then removed and centrifuged till they become a two-layered liquid, the bottom layer of which contains the evidence.
These are reacted with chemicals called "derivatising reagents". Then one microlitre of the solution is inserted in a 25-metre long tube in the spectrometer, called the capillary column. It is heated to 200 Celsius and helium carrier gas flows constantly through the tube as the molecules pass through in an order determined by their volatility.
Results are measured on a graph which is compared with the graph read-outs of known substances. After these fragments are measured and counted, the results are calculated on computer in a manner analogous to fingerprinting and compared to a standard analysis of clean urine.