Emergency fixtures and emergency fixture mixing valve standards, Part 1

Employers are required by Occupational Safety and Health Administration (OSHA) guidelines to provide a safe work environment for workers. This includes providing safety equipment for workers in hazardous work environments in case of an accident.

The Occupational Safety and Health Act of 1970 was enacted into law to ensure that workers are provided with safe and healthy working conditions. Under this law, a new division of the U.S. Government was created. It was called the Occupational Safety and Health Administration (OSHA). OSHA was created and authorized to adopt safety standards and regulations to fulfill the mandate of improving worker safety.

OSHA directs compliance initiatives in the U.S. and their territories for occupational safety and health and requires businesses to protect their workers and reduce the number of workplace deaths, injuries and illnesses. When employees stay safe and healthy, it saves lives and it reduces costs to employers for insurance, medical costs, training for return-to-work programs and elimination of unsafe machinery among many other things, including fines.

Since the enactment of the act in 1970, workplace deaths have been cut by more than 60 percent and occupational injuries and illnesses have declined over 40 percent. In addition, OSHA conducts workplace inspections and issues citations for safety violations.

OSHA makes sure their OSHA Regulations are followed to provide safety training to employers and employees. When there has been a workplace accident that injures or kills a worker, they issue citations or fines to companies for failing to comply with OSHA Regulations if fault is found with the company's safety procedures. They work to find innovative ways to deal with workplace hazards and minimize safety risks. They work with employers to require record keeping and reporting requirements with respect to safety inspections and issues. They work to develop training programs for occupational safety and health personnel and they also partner with states that operate their own occupational safety and health programs.

OSHA regulations or standards require employers to:

1. Maintain conditions and/or adopt practices necessary and appropriate to protect workers on the job.

2. Become familiar with, and comply with standards applicable to their workplace.

3. Ensure that employees have and use personal protective equipment when required for safety and health.

In addition, the Occupational Safety and Health Act instituted a “general duty clause” (Section 5(a)(1) which requires that each employer: “furnish … a place of employment which is free from recognized hazards that are causing or are likely to cause death or serious physical harm to their employees.”

When companies work with, or around, hazardous chemicals they shall provide emergency showers and eyewashes.

OSHA已经采取了若干规定,参考the use of emergency eyewash and shower equipment. The primary regulation is contained in the Code of Federal Regulations, 29 CFR 1910.151, which states: “...where the eyes or body of any person may be exposed to injurious corrosive materials, suitable facilities for quick drenching or flushing of the eyes and body shall be provided within the work area for immediate emergency use.”

Emergency fixture standard

The only industry standard for emergency showers and eyewashes is developed by the International Safety Equipment Association (ISEA) using a consensus process and following the American National Standards Institute (ANSI) guidelines for development of an American National Standard. The standard is titled, “ANSI ISEA Z358.1 American National Standard for Emergency Eyewash and Shower Equipment.” The ISEA Z358.1 standard covers plumbed and self-contained emergency showers and emergency eyewash equipment, eye/face wash equipment, combination units, personal wash units and hand-held drench hoses. These systems are found in manufacturing facilities, construction sites, laboratories, medical offices, and other workplaces where hazardous materials are present.

ANSI Z358.1 standard

ISEA的权威docu Z358.1标准ment that specifies minimum performance criteria for flow rates, temperature, and drenching patterns – all characteristics that are important for a user to receive adequate rinsing of a contaminant in an emergency situation. Equally as important are the requirements and maintenance directives for the installer to ensure that the equipment is available in proper working condition in defined locations.

ANSI/ISEA Z358.1-2009 was prepared by ISEA and was reviewed by a consensus panel of stakeholders representing architects, design professionals, health care facilities, chemical and safety professionals, and government agencies.

Among the most notable revisions in the 2009 edition is the inclusion of defined temperature parameters for flushing fluid delivery. The standard defines a suitable delivery temperature of 60ºF -100ºF, the standard seeks to ensure that the victim continues flushing the affected area to minimize any damage.

Other significant changes from the 2004 version include clarification of certification procedures that allows for freedom in designing compliant equipment and the expansion of criteria for personal washes to ensure that they meet any applicable regulatory requirements. Additionally, illustrations have been updated to reflect design configurations that are known to meet the criteria in the standard.

When a corrosive chemical comes in contact with eyes or skin, tissue damage can begin immediately. The rate and extent of this damage depends upon the chemical involved and the most important step in halting the damage is flushing the affected area immediately with large amounts of water for a minimum of 15 minutes. Quick access to flushing reduces the risk of long-term tissue damage. If the flushing is delayed or cut short, because of a long distance to the emergency equipment or flushing water or fluid that is too cold, first aid treatment (flushing) is less effective, and the full extent of the injury becomes more serious. If the skin receives serious chemical burns, the body can be exposed to infections because of the loss of skin which can lead to sepsis infection and death.

合理的灌溉正确设计变得更加容易ning, locating and maintaining emergency shower and eyewash equipment. The emergency fixtures are designed to wash chemicals from the whole body, the eyes and face, or specific areas.

The history of emergency equipment

Although emergency shower and eyewash stations have been installed using common shower heads as part of the workplace for more than 70 years, it wasn't until 1981 that a comprehensive industry standard was developed and published.

With the coordinated efforts of the International Safety Equipment Association, manufacturers, industry, labor, government, and the medical community, worked together as a consensus group, culminating in the creation of the ANSI Standard Z358.1, first issued in 1981. I have contributed to the review process and update of the Standard. I understand that it was in the late 1970s that a manufacturer of drinking fountains, Haws Corporation in Sparks, Nev., was approached by industrial users with a large order for their drinking fountain bubblers.

The manufacturer was curious why someone was buying so many bubblers, but no drinking fountain fixture so they inquired as to what they were being used for. They found out the industrial user was trying to comply with the new OSHA safety requirements by building a home-made emergency eye wash unit for an industrial application. The user told them that by using two drinking fountain bubblers that were facing each other and adjusting the laminar flow arcs of water with the flow adjustment it was ideal for washing the eyes and face without having too much water pressure. The manufacturer soon realized there was a specific market for emergency equipment and they developed new emergency fixture product lines for the purpose of flushing the body and eyes as industrial safety equipment. The rest is history.

A reference to the "ANSI ISEA Z-358.1 Standard" was first included in the 2003 International Plumbing Code from a code change that I submitted prior to publication of the 2003 plumbing code which addressed installation requirements for emergency fixtures. Prior to 2003, the code simply stated that emergency fixtures needed an adequate supply of cold water. That code language did not address hypothermia issues in colder climates. The ANSI ISEA Z358.1 had been published and available for many years, yet was not referenced in the code. The standard had been successfully referred to by planners, engineers, contractors, hygienists, and safety consultants as the industry standard on how to design emergency shower and eyewash equipment installations and it provides uniform minimum requirements for equipment performance, location and temperature limitations, but it was not mandated in the code. The standard also provides information regarding installation, testing, maintenance, and training. Since 2003, the reference to the ISEA standard has been in the code.

Emergency fixture mixing valve standard

A few years ago, the American Society of Sanitary Engineering International (ASSE) developed a new standard for temperature actuated mixing valves intended for use with emergency fixtures. This standard complements the ANSI ISEA Z358.1 standard. The ASSE standard is titled, “ASSE 1071 - Temperature Actuated Mixing Valves for Plumbed Emergency Equipment.” There is a distinct difference between a temperature actuated mixing valve designed for use in a plumbing system and a temperature actuated mixing valve designed for use with emergency fixtures.

The mixing valve intended for use with emergency fixtures is designed to open a full cold water bypass in the event of valve failure. If the temperature exceeds a preset limit, it will still supply cold water, whereas an ASSE 1017 mixing valve will slide the shuttle over to compensate for a high temperature system. If a 1017 valve is installed and there is a cold water failure, the ASSE 1071 mixing valve is not supposed to leak enough cold water to allow an eye wash to function. Some models of ASSE 1017 valve will allow enough hot water to bypass or leak pass the shuttle and it could mean scalding hot water directed to the eye wash fixtures. It is for this reason the cold water bypass function is very important.

If the 1071 mixing valve fails, the theory is the cold water will bypass and a cold water flush is better than scalding hot water or no water at all. The eyes can be damaged with temperatures in excess of 100ºF. It is for this reason you cannot use an ASSE 1017 temperature actuated mixing valve which is intended for plumbing systems on an emergency fixture system. Unfortunately, I see ASSE 1017 mixing valves used for emergency fixture installations on a regular basis by engineers or contractors that do not understand the difference in these types of valves. The ANSI ISEA Z 358.1 standard and the ASSE standard 1071 are intended to work together to provide a safe installation. The model plumbing codes require the installation of emergency showers to meet the requirements of ANSI ISEA Z358.1.

Water temperatures

The older editions of the ANSI Z358.1 standard addressed the subject of flushing fluid temperatures a little different than it is reference now. The standard now refers to the temperature of the flushing fluid as "tepid" temperatures, and defines it as being:

Tepid - Moderately warm or lukewarm. Medical references support tepid temperatures in first aid treatment for a majority of chemical exposures, and providing water at a temperature conducive to use is considered an integral part of providing suitable first aid facilities.

术语“温水”出生在一个最近的edition of the ANSI Z358.1 standard to describe the temperature of the flushing fluid because they could not use the term “tempered water.” That is because “tempered water” is defined in the model plumbing codes with a specific temperature range of 85ºF to 110ºF , and that is not an appropriate temperature range for emergency fixtures so a new term of Tepid was chosen.

2009年版本的ANSI ISEA Z358.1标准states that the water temperature delivered by emergency equipment should be “tepid” (60ºF to 100ºF). However, where it is possible that a chemical reaction might be accelerated by warm water, a medical professional (and/or a chemist) should be consulted to determine what the optimum water temperature would be for a given application. The mandating of a specific tepid water temperature to emergency equipment could raise complicated medical, engineering and liability issues. At a minimum, all emergency fixtures should be provided with tepid water through an approved temperature actuated mixing valve conforming to ASSE 1071 so that the mixing valve can be adjusted so that outlet temperature of the tepid water system can be supplied to the emergency fixtures at whatever temperature is required for the application.

This will mean that design professionals should provide both hot and cold water for an emergency fixture water system and calculate that there will be an adequate supply of hot water to be able to mix with cold water at the desired temperature for the full 15-minute duration with all of the anticipated emergency fixtures in use simultaneously for a given emergency. This will require special consideration for the hot water system design and the installation of ASSE 1071 mixing valves where required to mix the water to the desired temperature. Many owners, design professionals and contractors have used master mixing valves to supply multiple emergency fixtures. This can create a condition where the water in the emergency fixture loop can go ambient and become stagnant. Proper flushing procedures should be followed to assure that flushing water from the fixture also flushes the water main and branches serving the emergency fixtures. This most likely will require more than a 5 gallon bucket for flushing of the fixtures.

Medical professionals recommend that tepid flushing fluids be used to treat chemically injured eyes and body tissue. Temperatures that exceed 100°F can enhance chemical interaction with the eyes and skin. Additionally, flushing fluid temperatures below 60°F can cause hypothermic shock. The ANSI Z358.1-2009 standard states that while cooler flushing fluids may provide immediate relief after chemical contact, (prolonged exposure to cold fluids affect the ability to maintain adequate body temperature and can result in the injured person prematurely stepping out of the first aid treatment before all of the chemicals are washed off).

Access to an adequate supply of hot water in a volume sufficient enough to allow a 15-minute flush of an emergency shower and eye wash is necessary for emergency fixtures and can be achieved through a properly sized storage type water heater, instantaneous water heaters, and with a mixing valve conforming to ASSE 1071. For large systems a recirculation system can be employed. Flush is a very important part of having emergency fixtures that are ready with a clean supply of water in case of an emergency. During the winter months, many areas in the U.S. have ground water that can get below 40ºF. Temperatures below about 60ºF-70ºF are not conducive to a 15-minute flush because it is very uncomfortable and it causes Hypothermia. As water temperatures get below 70ºF stepping into the shower can take your breath away.

Eyewash stations and drench shower units that are exposed to freezing temperatures must be protected from freezing. The emergency fixture standard states addresses where the possibility of freezing conditions exists, equipment shall be protected from freezing or freeze-protected equipment shall be installed.” Freeze protection valves are a cost-effective way to prevent water from freezing in supply pipes and within the flushing stations. Additionally, heat trace units, heater jackets, and freeze protected eyewash equipment can be used to prevent the freezing of flushing stations.

地方环境水温may exceed 100°F, or piping may be exposed to direct sunlight, provisions should be made to minimize the escalation of the water temperatures. Consider burying the piping or provide jacketed insulating thick enough to address the extreme temperatures. This can be done with temperature sensors, flushing valves and insulation should be used to purge potentially scalding water from the supply lines. This may include outdoor locations that are exposed to direct sunlight, or indoor locations that may be exposed to extreme temperatures from steam or hot water mains or other high temperature equipment, machinery or manufacturing processes.

Emergency fixture water temperature research

I investigated and prepared a report for a power plant that had lots of emergency fixtures. Many of the emergency fixtures were outdoors serving acid loading stations and chemical drum buildings where truckloads of acid and chemicals were transferred and offloaded for use at the facility. It was 22 degrees below zero on one of the days of my inspection. Many of the emergency fixtures were through the wall outdoor emergency showers with a control handle thru the wall. One installation required the employee if exposed to go up two steps, find a door, open the door and go down several steps inside the building to the emergency fixture location in the corner of a mechanical room. There can be no obstructions in the path, including steps and doors. Access to the fixture is important and falling down stairs with acid in your eyes would not be accessible or a pleasant experience. I’m sure if we tested the outdoor fixtures on that day we would have been making snow and it would have been an icy mess on the ground.

许多单位在这个电厂进行了测试weekly by maintenance staff and the results were recorded on maintenance charts. Many of the units were marked with signs that they were “out of service” for various reasons. There were problems with the water temperatures. Some were installed with the wrong type of ASSE mixing valves. They used ASSE 1017 mixing valves instead of ASSE 1071 mixing valves. Other emergency fixtures could not be used or were taken out of service because there were problems with the water temperature when they operated the emergency fixture. Some emergency fixtures could not maintain the temperatures because they were not designed for emergency shower flow rates. They used a mixing valve for the eyewash to supply a combination eye/face wash and shower unit.

Other installations had the proper ASSE 1071 type mixing valves, but the cold water mains serving the emergency fixtures were run above and very close to high pressure steam mains which were over 300ºF, and it caused the cold water in the emergency fixture water supply to get very hot. In some cases, they were mixing 114ºF cold water with 140ºF hot water and they could not get tepid water at the emergency fixtures. In other locations they had numerous outdoor installations at the acid and caustic loading stations and outside battery rooms where there was an emergency shower pipe thru the wall. It was -22ºF, with 25 mile per hour winds on the day of my inspection. They would have been making snow if we tested them on those days. The recommendation was to use heated enclosures at those locations.

I have done some research to determine a suitable temperature range for a client. I tested the water temperature at a fixture with a thermometer and recorded the water temperatures while immersing my hand and arm in the flow of the water and noting my comfort level. We determined that 60ºF would be too cold for an adequate flushing temperature and would not be conducive to someone with chemical exposure staying in the emergency shower for the entire 15-minute period recommended by the standard. When the water temperature from the shower was set to 72ºF, it was still very cold but I determined it was possible that I could stay in the water for 15 minutes if I had to. The 72ºF sounds comfortable if it was the air temperature for a furnace thermostat setting. But, when you are dealing with flowing water and evaporative cooling there is quite a bit of a wind chill effect. If the shower was outdoors in freezing temperatures, the wind chill effect becomes more extreme and 72ºF may not be tolerable.

For employee safety, it is important to provide heated enclosures and tepid water to encourage use of the emergency fixtures. So, with a quick look at a wind chill factor chart, the wind chill factor for 60ºF water with an outdoor temperature of -20 and a 25 mile per hour wind, the wind chill chart for bare exposed skin temperature states it would feel like about minus 58ºF. Given some warming effect of 60 degree water the wind chill effect would still probably feel like it was below freezing. That is very cold and would likely cause someone to not fully flush the chemicals off. If they stayed in the water, they would suffer from hypothermia very quickly.

I was mildly uncomfortable in a room with 72ºF air temperature, no wind speed and water at 72ºF, and if I had chemicals splashed on me I might have been able to force myself to stay in the water, but it would not be pleasant. I am pretty sure I would not stay in the emergency shower stream of water for the full 15 minutes in a cold climate with high winds. I am not aware of any official testing to see what the minimum shower temperature should be to prevent hypothermia. Much of the hypothermia studies involve being submerged in water. When I did some research on my own, I found lots of information from the coast guard, navy, boating clubs and ice fishing groups with information on hypothermia for someone submerged in icy cold water. That is not the same as having water flowing over your body and being exposed to a wind chill factor. A person submerged in water will develop a boundary layer of warm water around them that helps their body temperature as long as they do not move too much. When someone is in moving or flowing water like that from an emergency shower, there is a constant removal of body heat that can reduce the time required for hypothermia to affect someone.

As a designer, it should not matter what the temperature requirement is for a given application, as long as there is a temperature actuated mixing valve that meets the ASSE 1071 standard with a cold water bypass installed in the system that is vandal resistant and adjustable by the facility personnel and designed for the minimum and maximum flows it will see in the system. The facility safety person is ultimately responsible for determining the proper temperature and checking to make sure the setting the temperature of the mixing valves comply with their requirements and testing them on a regular basis to ensure the temperature and flow is adequate for the particular installation and flushing them regularly to assure there is an adequate supply of clean flushing fluid.

Emergency fixture piping materials

Emergency fixtures are often supplied with galvanized pipe material because of the strength of the galvanized steel pipe serving as both a support and a water supply pipe other pipe materials. There is a drawback to the structural strength of the galvanized pipe. I have found that galvanized pipe tends to corrode and rust and provide a rough surface where bacteria and biofilm can grow. The first flush of water from units with galvanized pipe that have not been flushed properly can be rusty, bacteria rich flushing fluid. I would prefer an NSF approved epoxy coating on the interior of these fixtures to eliminate the exposed zinc galvanizing coating. Another option is to specify stainless steel or copper for the plumbed waterways on emergency fixtures.

A flushing solution

There are many design considerations and maintenance issues with emergency fixtures that need to be considered. When an emergency water system is installed serving multiple fixtures it can be easy for building maintenance to neglect the weekly flushing requirements called for in the standard. I find many installations are flushed very weakly instead of weekly. There are requirements in some government hospitals for fixtures to be flushed more often than weekly. In other countries, like Germany, they have a law that requires all fixtures to be flushed every three days and the flushing must be documented. Improper flushing can create a stagnant water condition. Stagnant water can allow water treatment chemicals to dissipate and bacteria of all kinds can grow to high levels in stagnant water.

我参与了炉前的一项调查plosion and fire in an industrial facility a few years ago where a worker on scaffolding was blasted in the face and chest with a ball of fire from a furnace he was working on high above the floor. He held on and was burned for longer than usual because he did not want to fall. He eventually got out of harm’s way ran to an emergency shower and eyewash station in the facility to cool his burns with water. When he opened the emergency fixture valve it had not been flushed for a very long time. The first several minutes of flushing was with smelly black and orange water laden with bacteria flushing all over his burn injuries. Instead of helping, the emergency fixture made his burn injuries worse by flushing bacteria into his burns. Proper maintenance and scheduled flushing of the emergency fixtures would have helped in this application. Emergency fixtures need to be ready with a supply of clean water.

There is a company that offers an automatic flushing system that can monitor every part of the plumbing system and automatically flush areas of the building that have not been flushed with normal usage within a specified time period. The system also records the results for documenting the flushing. This type of system would be ideal for use with emergency fixture water systems to assure a clean supply of water for flushing of chemical burns. This is similar to the drinking water bubbler example. There is an application for an existing technology. We just need to put them together.

It’s like the guy who got peanut butter on the chocolate bar or was it chocolate in his peanut butter. It was an accident that led to a great idea. It should be just a short time before emergency fixture manufacturers offer automatic flushing systems.

Emergency fixture Inspection, maintenance and flushing

Weekly (or more often) Flushing Activation and Emergency Fixture Inspection Checklist

(Refer to ANSI ISEA Z358.1-2009 American National Standard for Emergency Eyewash and Shower Equipment Refer to sections 4.5, 4.6, 5.4, 5.5, 6.4, 6.5, 7.4, 7.5, and Appendices)

Survey the facility to ensure that the appropriate emergency shower or eye/face wash flushing system is installed within ten seconds or 50 feet from the hazard with no obstructions in the path. These units should be adjacent to the hazard if very serious hazards exist.

Notes

1. Material Safety Data Sheets (MSDS) or Safety Data Sheets (SDS) can help determine what flushing system is appropriate for your hazards.

2. Note travel path and stored materials that can block access.

Inspecting the emergency fixtures

Activate all eyewashes, drench showers and drench hose systems on the schedule provided in a water management plan to ensure the emergency water systems are compliant and operational in case of an emergency. Activation clears sediment bacteria and provides fresh water treatment chemicals in the supply line.

1. Replace any broken or missing parts immediately.

2. Remove any obstructions or trip hazards.

3. Ensure the system is on the same plane as the hazard.

4. Be aware that a door may be considered an obstruction if corrosive chemicals are present.

5. Protect equipment against freezing.

6. If a freeze protection valve is attached to bleed off cold water, be sure to funnel this water away from the system as it may be a slip hazard.

7. Evaluate if the user should be protected against scalding water.

8. If a scald protection valve is attached to bleed off hot water, be sure to funnel this water away from the system as it may be a slip hazard.

9. Consider an enclosed system if injured party may be exposed to freezing temperatures.

10. Self-contained eyewashes and drench showers must be visually inspected on a weekly basis to ensure they are ready for use.

11. Personal wash (supplemental) fixtures (i.e. bottle eyewash, single-head drench hoses) should be protected from freezing.

12. Ensure isolation valves controlling water supplies to these fixtures are locked open.

13. Ensure these fixtures are well marked to be easily found and identified.

NOTE: Personal wash systems are considered supplemental equipment and must be coupled with a plumbed system that provides a full 15-minute compliant flush, according to ANSI.

Measure the water released from the eyewash (min. 0.4gpm) or eye/face wash (3.0 gpm) system to ensure it is compliant. (A flow meter or measuring bucket is recommended).

1. Use a test gauge to determine if the flow pattern is compliant to the ANSI Z358.1-2009 standard.

Use a drench shower tester with a bucket to contain the water released from the drench shower.

1. Measure the water released from the shower to ensure it complies with the 20gpm ANSI minimum flow requirement.

2. Consider installing a shower flow control, if not already present, to limit the flow of water through the shower. As a reminder, a compliant showerhead with flow restrictor releases a minimum of 20gpm per minute, which equates to 300 gallons of water over a period of 15 minutes for a full 15-minute operational compliance test. Modified buckets with fire hose drains can be used to direct the water to a safe place of disposal.

3. If both the eye/face wash and shower are used, flow would be 23 gpm, for a total of 345 gallons.

Determine if it is in the organization and/or the employee's best interest to install either flow switch alarms or flow switches alone to alert the designated safety personnel that an emergency occurred.

1. Alarms are frequently requested to discourage false activations and save the facility from water damage.

Evaluate if there is a need for heated enclosures, privacy curtains on drench showers, to encourage immediate flushing.

Test the water temperature using an industrial thermometer to ensure it is tepid (60ºF-100ºF, 15.5º-37.7ºC), Ideally 80ºF (this depends on the individual and should be left to the discretion of the owner. 75-85ºF is a more appropriate recommendation) would encourage an injured party to complete the full 15-minute flush during an emergency and should be the target temperature.

Document activations on the unit’s inspection tag and in any centrally-controlled documentation log.

You can obtain a copy of the ANSI ISEA Z358.1 American National Standard for Emergency Eyewash and Shower Equipment at the following address:

The ANSI ISEA Z358.1 American National Standard for Emergency Eyewash and Shower Equipment is published by the International Safety Equipment Association – 1901 North Moore Street, Suite 808, Arlington, Va., 22209. Phone: (703)525-1695.

Ron George, CPD, is president of Plumb-Tech Design & Consulting Services LLC. Visitwww.Plumb-TechLLC.com.