Page 32 - OHS, January/February 2022

EMERGENCY EYEWASH & SHOWERS
Don’t Let Your Liquid Assets Become Frozen
How to ensure reliable heated water for drench showers and eyewashes.
TBY RYAN PFUND
he realities of weather are always
present on a job site and must be carefully considered by safety managers. Fortunately, today’s
advanced water heating technologies make emergency drench showers and eyewashes fully operational 365 days per year, whether it’s or -40 degrees Fahrenheit sub-zero or 120 degrees Fahrenheit above zero.
Extreme environments can lead to many concerns when it comes to safety showers. Sub-zero temperatures can cause pipes to break or burst and cause systemic damage affecting the usability of the safety equipment.1 ANSI/ISEA Z358.1 Section 4.5.5 states, “Where the possibility of freezing conditions exists, the emergency shower shall be protected from freezing or freeze-protected equipment shall be installed.”
No matter the weather, the current ANSI/ISEA Z358.1–2014 American National Standard for Emergency Eyewash and Shower Equipment calls for emergency eyewashes and drench showers to deliver tepid water (60–100° F/15.5– 37.7° C) for a full 15 minutes to ensure adequate flushing of hazardous materials from users’ bodies and/or eyes. For drench showers the minimum flow rate is 20 GPM (76 L-MIN), for Eye/Face Wash the minimum flow rate is 3.0 GPM (11.4 L-MIN) and for Eye Wash the minimum flow rate is 0.4 GPM (1.5 L-MIN).
Moreover, it’s recommended that eyewash stations be within 10 seconds or 55 feet (17 meters) from a potential hazard. In some cases, it is necessary to supply heated water to more than one safety shower simultaneously. The water for all equipment must sustain the required temperature, volume and flow for the requisite amount of time needed.
The bottom line is to ensure that all plumbed emergency safety equipment— despite any environmental conditions— has access to properly heated water to help avoid worker injury, prevent workers from having to use ice cold water (or discovering the pipes are frozen) in the event of an emergency, and avoid equipment downtime and costly repairs.
Freeze-Protection Options
The following are adaptable safety shower products and engineered solutions that help meet ANSI/ISEA requirements in both freezing and challenging settings, including enclosed safety showers, heat trace units, frost-proof units, gravity fed units as well as electric tankless water heaters used to supply water to these units.
Enclosed Safety Showers. When harsh environments—extreme weather and highly corrosive conditions—can affect the performance of emergency safety fixtures, enclosed safety showers are necessary for providing a safe refuge. No matter what unique environmental conditions exist, these units can be custom engineered to any particular application with turnkey shower, eyewash and drench hose systems.
These freestanding units are insulated and heated to keep the internal temperature warm down to -40 degrees Fahrenheit (-32 degrees Celsius), making them ideal for sub-zero applications. They also include lighting and a signaling system to provide an audible/visual notification when the safety shower has been activated. The signaling system can also be tied into a remote monitoring facility for faster response.
While some units require a plumbed water supply, there are also self-contained units that will only require a full tank of water and a constant power source. Enclosed safety showers feature the ability to provide tepid water via a tepid water inlet, a hot water tank and a thermostatic mixing valve, a heated self-contained storage tank, or a tankless hot water heater. In accordance with ANSI/ISEA Z358.1 Section 7.4.4, safety systems such as enclosed safety showers with multiple drenching platforms (shower, eyewash and drench hose) must be capable of simultaneous activation while delivering tepid water for 15 minutes.
It is important for these units to be certified to ANSI Z358.1 and consider local electrical (CEC AND NEC) codes along with any explosive atmospheres that may be present. When necessary, these
units can be built for Class 1 Division 1 or Class 1 Division 2 hazardous locations.
In all, enclosed safety showers address the physical and psychological needs of the injured party by providing privacy, delivering unlimited tempered water, warm ambient temperature and a shelter from the elements.
Heat Trace Units. Heat trace units guard against frigid temperatures so that water does not freeze in the fixture, putting safety fixtures at risk for frozen pipes and parts. These specialized showers, available as combination shower and eyewash units, feature insulated jackets over an electrical heat trace cable that wrap the piping and protects the water from freezing. Should power fail in cold temperatures, these units feature a freeze protection valve that will open when the water temperature drops below 35 degrees Fahrenheit and bleed out water until it warms up again.
Some units are protected from freezing down to -50 degrees Fahrenheit (-46 degrees Celsius). Like enclosed safety showers, these showers can be built for Class 1 Division 1, Class 1 Division 2 and Class 2 Division 2 hazardous locations. An indicator light can be included to show when power is on and when the heat trace cable is heating the unit.
In areas where high winds are prevalent, some units feature entire bowls and bowl covers to protect against wind, debris and weather. In especially harsh environments, stainless steel eyewash bowls with covers may be used for extra protection from the elements. These models come standard but are configurable as well.
Self-contained Safety Fixtures.
When a work environment does not have plumbed water, self-contained, portable gravity fed eyewash units can be an excellent choice. These convenient systems incorporate water tanks that provide adequate water volume to complete a full 15-minute flush of the eyes at the ANSI-mandated flow rate. Some units are designed with hinged eyewash trays that may be activated in one quick motion, while stainless steel clamp mechanisms secure the tank during transport.
28 Occupational Health & Safety | JANUARY/FEBRUARY 2022
www.ohsonline.com