Eyewash Solutions

According to the American National Standards Institute Standards (ANSI), which also apply to Canadian workplaces, the "flushing fluid" or eyewash solutions can be defined as potable (drinking) water, preserved water, preserved buffered saline solution and other medically acceptable solutions.

1. Drinkable tap water may not be the best solution for flushing away hazardous substances.  Tap water often contains contaminants, such as chlorine, rust, scale and other trace chemicals, which can aggravate the problem.  Plumbed eyewash stations should use water that is tested periodically and treated to remove contaminants

2. Portable Eyewash Stations have a limited amount of fluid and therefore regular maintenance is required to ensure that the units are fully filled at all times.

3. Eyewash Solution have a limited shelf life.  Amoebae have been found in these solutions and therefore it is important to monitor the shelf life of these products and replace any expired solutions.

4. Eyewash Bottles do not replace the ANSI Z358.1-2004 "Emergency Eyewash and Shower Equipment" recommended eyewash stations.  They allow for immediate flushing of contaminants.  Once this is complete, the casualty should be taken quickly to the ANSI recommended eyewash station.

The affected area should be flushed immediately and thoroughly for at least 15 minutes with lots of clean fluid under low pressure.  Because water does not neutralize the contaminants, large amounts of water are required.

Enclosed below is a guide to the length of time to flush an affected area dependant on the type of contamination:

1. Mildly irritating chemicals - minimum of 5 minute flushing time
2. Moderate to severe irritants - minimum of 20 minutes
3. Non-penetrating corrosives - minimum of 20 minutes
4. Penetrating corrosives - minimum of 60 minutes

If the irritation persists, repeat the flushing.  Ensure that the casualty seeks medical attention as soon as possible.

ANSI Z358.1-2004 recommends that the solution be "tepid" under 38C (100F) and above 15.5C (60F). Temperatures higher than 38C (100F) are harmful to the eyes and can enhance chemical interaction with the skin and eyes. Flushing with cold water less than 15.5C (60F) can cause hypothermia and may result in not rinsing or showering for the full recommended time (ANSI 2004). With thermal burns (injuries to the skin), the American Heart Association noted that optimal healing and lowest mortality rates are with water temperatures of 20-25C (68-77F).

Flushing can occur from 15-60 minutes and therefore, it is important that the water temperature be comfortable for the casualty.  Temperature control valves can help to maintain a consistent temperature and flow rate.