The routine maintenance of a hydraulic system may be the responsibility of a staff member without a background in the operation and repair of hydraulic machinery, who should follow a strict procedure with a checklist to ensure tasks are carried out in the right order and using the correct equipment. The replacement of hydraulic fluids is one area where extra care must be taken to use the right oil, as the average layperson may not distinguish between hydraulic oil and engine oil, or even fuel. Mistakes like this can be costly, and when equipment breaks down because of avoidable oversights it can undermine the integrity of the whole company; one silly mistake is usually a sign that other things are being overlooked. Maintenance procedures should be written by an experienced engineer, possibly working with a technical writer, to produce a document that is easy to follow and contains all the relevant information. Procedures should be tested several times to ensure there is no room for interpretation of instructions – ambiguity in procedural documents can lead to poor practises. It is worth adding pictures to a checklist, to further enable staff to comply with the procedure. Some people take in information better when it is presented in a visual format than in words, and vice versa so by using both forms of communication the document will be comprehensible by non-hydraulically savvy staff. There is one important ingredient in a checklist for hydraulic machinery maintenance and operation, and that is the “idiot test”. This refers to a step in a procedure or clause in a contract that clearly shows whether attention has been paid to detail. Some common examples are rock stars insisting on a bowl of sweets in their dressing room with a certain colour removed. This is not, as it appears on the face of it, brattish behaviour but a clever way of knowing whether or not standards have been followed throughout. If a simple task, like removing all the yellow sweets from a bowl, has not been done properly it is indicative of carelessness. The same concept applies for exams where the final instruction is to only answer one question – students who are not paying attention and are not interested in the bigger picture will answer every question before reading the last instruction. If you want to ensure that your hydraulic equipment is being used and maintained to the correct standards you can incorporate an “idiot test”, like having to note down the volume of hydraulic fluid that has been added, or signing materials in and out of a book. These are easily checked by a supervisor without arousing suspicion, and failure to complete the “idiot test” lets you know to check over that person's work and offer extra training. Of course, it is desirable to always have hydraulics savvy people undertaking maintenance and in some cases, the operation of equipment with a hydraulic motor, but this cannot always be achieved. Training courses in the operation of hydraulic equipment are essential for health and safety, but your ‘in house’ policies can always be tightened and tweaked to close any potential holes in procedure, and engineer out bad practise and common problems by refining your processes.