We may mock present-day Health and Safety regulations and make them the butt of many jokes, but we also understand they are there for a very good reason. Many areas of industry use machinery and other equipment that can, if not used with due care and attention, be dangerous. Accidents in the workplace do happen, and minimising the chances of injury from mis-use of equipment is one of the many requirements of an employer.
This is why, in recent years, many procedures have come into place that are designed to prevent or minimise the risk of injury in set situations. When a machine is undergoing maintenance or servicing, for example, it is essential that it cannot be made to operate for the safety of those performing the task. This is where lockout-tagout, or LOTO, comes into the picture. What is it, and when is it used?
What is LOTO?
Lockout-tagout works via a very simple routine, but it is one that needs to be carefully adhered to if it is to have the desired effect. The idea is that the person who shuts down the machine prior to its service or maintenance isolates and turns off the power supply. They are then required to lock it, a tag is placed upon it bearing their name, and they are the designated sole carrier of the key to unlock and restart the power supply.
The advantage is that there is only ever one person who can restart the power, and therefore the machine is rendered idle and inoperative while others are at work on it. In some countries this procedure is mandated by law, and there is usually a standardised routine that goes as follows:
- Announce shut off
- Identify energy sources
- Isolate energy sources
- Lock and tag energy sources
- Prove that the isolation is effective
The above procedure should be followed carefully and step-by-step every time, and the result is that the maintenance or service engineers can be sure they are working in a safe and stable environment.
Where is Lockout-Tagout Used?
There are many instances where the LOTO procedure should be used, as power sources within industrial complexes can be many and varied. The main source of power, of course, is the mains electricity, but things can be more complex than this and it should be left to an experienced operator with full knowledge of the machinery to carry the responsibility of the lockout-tagout routine.
In some cases, where machinery has one simple power source that needs to be isolated, LOTO is an easy procedure, but there can be exampled of many more danger sources, which should also be subject to the procedure. For example, some machines may have very hot or cold surfaces that need to be isolated, there may be blades that have their own power source, or it could be that a procedure involves more than one machine operating in conjunction. In these cases, when expert equipment may also be required, you should turn to companies like Substation Safety to make sure you have the right tools for the job.
The following are some of the potential danger sources that need to be attended to in the lockout-tagout process:
- Compressed air and pneumatic systems
- Kinetic systems – think springs and other tension devices
- Hydraulic systems
- Radiation – including thermal
- Certain liquids – including water
- Any movable parts
This is not a comprehensive list, but should give you an idea of what you need to know in order to make sure the LOTO procedure is carried out correctly, and that the machine cannot be restarted until the designated operator returns with the key or keys that are relevant to the tags in place.