Safety shower and eyewash - how do they differ and when are they required?
A safety shower and an eyewash serve different functions in the chemical first aid system. The shower is used to quickly rinse the entire body or a large area of it, whereas the eyewash is designed exclusively for rinsing the eyes and face with a gentle, dispersed stream of water. In laboratories where corrosive, irritating, or toxic substances are used, occupational health and safety regulations require the installation of both devices simultaneously - each neutralizes a different type of hazard.
There are three basic structural variants available on the market. Stationary devices are permanently connected to the water supply system and are operated with a single movement, hands-free. Combination stations integrate a combination emergency shower with an eyewash on a common supply column, which saves space when designing the laboratory furniture layout. Portable solutions, not connected to the water supply, are used where a permanent installation is impossible.
In rooms exposed to the constant presence of acid vapors, the choice of equipment material is crucial. Stainless steel and chemically resistant plastics do not corrode under the influence of an aggressive environment and retain full functionality for many years of operation. It is worth noting that manual eye wash bottles and rinses do not replace a stationary device - they are only a temporary supplement until the victim reaches the proper station.
In practice, a safety shower is intended to rinse the entire body or a large area of it with a strong stream of water and becomes essential when working with larger amounts of corrosive substances. An eyewash, on the other hand, provides a gentle, dispersed stream used exclusively for rinsing the eyes and face, and its installation is necessary wherever there is a risk of chemical contact with the eyes.
The EN 15154 standard - what does it specify for showers and eyewashes?
The EN 15154 standard is divided into parts corresponding to different types of devices. The section on laboratory showers specifies the requirements for stationary safety showers, another covers stationary eyewashes, and the others refer to devices without a water connection and showers installed outside laboratories, for example in industrial plants.
The standard specifies the minimum flow rate: a safety shower must provide at least 60 liters of water per minute, and a stationary eyewash - 6 liters per minute. Both types of devices must operate continuously for a minimum of 15 minutes without a pressure drop, which corresponds to the time recommended for effective decontamination.
The standard also determines the water stream distribution - the distance below the shower head and the radius of the circle that the stream should cover, so as to effectively rinse the entire body. Wall-mounted safety showers and ceiling-mounted safety showers must meet the same stream distribution parameters regardless of the installation method. Activating each device must be possible with a single movement (for example, using a pull rod or a push plate), and the valve must remain open automatically. This leaves the user's hands free during the entire decontamination process.
Comparing both devices: a safety shower requires a minimum flow of 60 liters per minute, and an eyewash - 6 liters per minute, while both must operate continuously for a minimum of 15 minutes, start with a single movement, and continue working without the need to hold the valve.
How far can the shower be from the workstation?
The primary requirement is that the time to reach the device must not exceed 10 seconds. In practice, this means that the injured person cannot cover more than about 20 meters, moving at a free pace on an obstacle-free path. This time limit directly stems from the physiology of chemical burns; the longer the corrosive substance remains in contact with the skin or eye, the deeper it penetrates the tissues.
The path to the shower must be completely free of obstacles, doors, and stairs. Any additional barrier extends the real reaction time beyond the allowable 10 seconds, even if the straight-line distance is within the norm. When working with highly corrosive substances, such as concentrated acids or bases, the recommended distance is shortened well below the maximum - the device should be located practically next to the workstation where the operations are performed.
In multi-space laboratories, consisting of several rooms or zones with different risk profiles, laboratory emergency showers and decontamination showers are placed separately near each hazard zone, and not exclusively at the building entrance. The location of the device must be marked with a visible pictogram and adequately lit, so that it can be located even in a stressful situation.
The location of the shower and eyewash is determined at the design stage of the decontamination infrastructure, and not after the room has been equipped with laboratory furniture and sinks. Such an approach avoids a situation where the finished layout of workstations interferes with the required distance or blocks free access to the rescue device.
Pressure, temperature, and drainage - what does the installation require?
The water supplying the shower and eyewash should have a temperature in the range of 15-37°C. Water that is too cold prompts the victim to stop rinsing before the required 15 minutes have elapsed, which limits the effectiveness of decontamination. Conversely, water that is too warm accelerates the absorption of certain chemicals through the skin and mucous membranes, exacerbating the effects of contact.
Maintaining the proper temperature is ensured by a mixing valve with thermostatic protection, which automatically limits the inflow of water that is too hot or too cold. The installation must also provide appropriate dynamic pressure and the correct supply diameter, although these requirements differ for the eyewash itself, the shower itself, and the combined device. The selection of appropriate laboratory fittings should be determined already at the installation design stage.
The drain must carry away the water corresponding to a full 15 minutes of uninterrupted device operation, which in practice means several hundred liters. A separate issue is water stagnation in a rarely used installation - standing water promotes the growth of bacteria, including Legionella, therefore regularly activating the device serves as both a test and a system flush.
How often should the shower and eyewash be tested?
Regular activation of the shower and eyewash serves two purposes simultaneously. First, it allows checking if the device is working properly. Second, it replaces the water stagnating in the system between uses, limiting the risk of biological stagnation.
During the test, several parameters are evaluated: the size and uniformity of the outflow, the correct stream distribution, the proper operation of the activating mechanism, and the water temperature at the outlet. The exact frequency of such tests is specified by the device manufacturer in the technical documentation, and the laboratory should strictly adhere to it, as it depends on the specific design of the valves and nozzles.
Regardless of functional tests, periodic technical inspections are carried out, performed less frequently and covering a broader scope - the condition of the thermostatic mixing valve, the tightness of connections, and the condition of mechanical elements. An important design detail are the eyewash flushing nozzles with dust caps, which protect the nozzles from contamination between uses.
These caps must be removed automatically when the device is activated, without any additional action from the injured person. This is one of the details worth paying attention to already when choosing the laboratory furniture equipment, because it translates directly into the quality and reliability of the rescue station.
Five mistakes that will prevent the shower from working when needed
The first mistake is blocked access to the device. A shelf, a laboratory cart, or a temporarily placed box can effectively block the path to the shower, which is why a constant, clear space must be maintained around the station - regardless of the laboratory's current organizational needs.
The second mistake is water in the installation being too cold. When the temperature drops below the required range, the victim instinctively stops rinsing long before the 15 minutes are up, which significantly reduces the effectiveness of decontamination. The solution is a mixing valve that maintains a constant temperature regardless of the season.
The third mistake is the lack of a proper drain. Without an efficient sewage system, several hundred liters of water from a full operating cycle of the device ends up on the laboratory floor, creating an additional slip hazard and hindering evacuation.
The fourth mistake is skipping periodic tests - water stagnating for months in an unused installation promotes bacterial growth and may reveal a fault only at the moment of real danger.
The fifth, often underestimated mistake is determining the location of the shower only after the furniture has been placed. Such an order leads to a collision with the laboratory bench, fume hood, or safety cabinet, and consequently to shortening the real, free access path. The proper approach, used for example in modular systems like RL6, assumes designating the location for laboratory benches, laboratory fume hoods, and safety stations already at the stage of the joint room layout design.
September 16, 2026