15 June 2021
Decontamination showers are necessary to ensure a worker can fully remove harmful substances before moving on to the next task and in the event of a spillage, the first 10 seconds following exposure are vital in minimising serious injuries. Here, Wendy Baker provides an insight to the health and safety guidelines.
PROTECTING THE health, safety and welfare of the workforce is the responsibility of every employer. Around 38% of industries, and subsequently their workforce, are exposed to hazardous chemical or biological substances. The risk of contamination and injury due to accidental spills is high. From anhydrous ammonia contained in refrigerants at food manufacturing sites and data storage centres, to acids and alkalis used in mining, whatever the environment access to Personal Protective Equipment (PPE) and methods of decontamination are essential.
Personal protective equipment (PPE) contributes to a safe workplace and is required by law to control substances that are hazardous to health. Specific site standards and detailed risk assessments help to determine the steps that need to be taken to protect the safety of employees. However, health and safety guidelines surrounding hazardous substances and decontamination can be difficult to decipher.
Guidelines often recommend the provision of ‘hygiene procedures’ or ‘washing facilities’ to ensure potentially harmful substances are removed before a worker moves on to another task or finishes work for the day. An ordinary shower or sink is not enough to achieve complete decontamination, especially in the event of an accidental spill or splash. Where a substance can cause harm or severe irritation to skin or eyes, the first 10 seconds following exposure is critical to minimise serious injury. It is imperative that a specifically designed emergency safety shower or eye/face wash is provided to effectively decontaminate in the event of an accident or to clean PPE prior to removal.
EN15154 and ANSI Z358.1-2014 are the European and International standards focused on the performance, use, installation, testing, maintenance and training of safety showers and eye wash equipment. While not legally binding, it is considered best practice to adhere to them to remain compliant. The stipulations and recommendations of these standards can only be met by specifically designed safety equipment. Here we outline some of the general considerations.
Water temperature: According to the European Standard EN15154, safety showers and eye/face wash equipment should deliver tepid water in the range of 15-38C. Adhering to these parameters can be the difference between life and death. The human body strives to maintain a steady internal temperature within a normal range of 32 to 38C. When the body encounters water temperature significantly above or below its core temperature, it instinctively reacts.
A higher water temperature may scald the injured person, adding temperature burns to their chemical injury. Hotter water may also cause skin to absorb more of the hazardous chemicals. The opposite reaction occurs when the body experiences extreme cold. Lower temperatures can lead to hypothermia or thermal shock. People are also less likely to remove contaminated clothing and PPE if the water is too cold. Clothes containing chemical residue will prolong exposure and exacerbate burns if not removed.
Whether the water is scalding or freezing, the natural human reaction is to withdraw from the temperature extreme to protect the body. At least 15 minutes of flushing is recommended to completely rinse away most hazardous chemicals. The only way to ensure this length of time is adhered to is to control the water temperature in the tepid range.
Flow Rate: Emergency showers deliver a water flow of at least 76 litres per minute for 15 minutes. This provides enough time to remove contaminated clothing and rinse thoroughly. If the flow rate is too low, hazardous chemicals may not be completely washed off the skin leading to ongoing chemical burns. Water flow from emergency showers is much greater than the standard home shower head, which averages 8-11 litres per minute of flow. The dangers of hazardous chemicals vary by each chemical’s specific properties, however in general a deluge of water is required to wash them away. Eye/face wash equipment must deliver at least 12 litres per minute for 15 minutes to ensure a complete decontamination. Features such as aerated diffusers and individual flow controllers ensure the eye wash provides a gentle washing action without causing any further injury.
Operation: Emergency safety shower stations must be accessible and easy to-operate, even with impaired vision. Safety showers and eye wash valves are designed so the flushing flow remains on without the use of the operator’s hands. The control valve must go from ‘off’ to ‘on’ in one second or less.
Location: Installation of this equipment should be within 20 metres, or 10 seconds reach, of the hazard without stairs, ramps, or obstacles in the path. Obviously, it must be located in a clearly visible, easily identifiable position as a casualty would find it difficult to negotiate doors or partitions.
Decontamination solutions in challenging environments
How does a health and safety specifier select a shower that will maintain a tepid water supply when the site is remote, and perhaps has no mains water supply? What if a water supply does exist but operates at low flow or pressure? Perhaps the ambient conditions are in the extremes and are at risk of overheating or freezing? There are several types of emergency safety showers available for differing environments, each aimed at maintaining a tepid temperature.
Gravity fed tank showers incorporate an integrated overhead tank capable of storing enough water to deliver a 15-minute decontamination. With the addition of immersion heaters or cooling systems, dependent upon the ambient temperature, they ensure the water delivered is tepid.
Temperature controlled emergency safety showers feature an integral heated water tank designed to remain on standby to provide tepid water whatever the conditions.
Trace tape heating and insulation provide frost protection to outdoor tubular models and prevent the water inside the shower freezing.
In extreme hot climates, static water within the pipework can rise as high as 50C due to solar radiation. Self-draining showers drain water from the standpipes after each activation to avoid exposing the casualty to such elevated temperatures.
Protect your investment in safety
This specialised equipment must be regularly tested and maintained to ensure it operates first time, every time during its lifetime. Weekly activations, visual inspections and a routine servicing schedule are all advised by EN and ANSI standards. In remote locations or expansive sites this can be challenging. It requires manpower. The importance of tepid water, flow rate and reliable operation all contribute to the functionality of safety showers and eye/face washes and need to be monitored. Fortunately, digitalization of manufacturing is set to make a significant impact on industry operations.
Smart, or remote, monitoring of safety showers allows record keeping of testing. Periodical flushes are automatically logged and stored in a secure cloud platform meaning the need for onsite physical record keeping and checks are no longer required. Dashboard reporting of numerous parameters can be viewed and documented in real-time, around the clock. Most importantly, if a safety shower is activated, or non-compliant results are detected posing a risk of failure, alerts are sent to the relevant people as fast as possible, for example via email or SMS alert.
Smart technology has helped businesses to adapt the way they operate, and it now looks set to change the way we monitor safety measures.
The safety of the workforce is paramount. While standard hygiene facilities have their place as part of workplace health and safety, in the case of hazardous substances they cannot replace the efficiency and effectiveness of precisely designed emergency safety showers and eye wash equipment to provide a full decontamination process.
Wendy Baker is marketing manager at Hughes Safety Showers. For more information, visit www.hughes-safety.com