Eye washes :- 1.5 L per minute for 15 minutes
Safety Showers:- 76 L per minute for 15 minutes
Therefore the SE590A with a 45 or 106 L cylinder do meet the standards for eyewash, however not for a safety shower.
Therefore the Safety shower (on the 106 L cylinder) and the Drench Hose (on the 45L cylinder) can be described as Supplementary body washes intended as a support system, not in place of Primary Emergency Response Systems.
Below are some relevant parts of AS4775 to assist you in your decision:-
AS 4775 Emergency Eye wash & Shower Equipment
Section: 7 Plumbed and Self -Contained Eyewash Equipment
7.2 Performance of plumbed and self-contained eyewash units
When activated plumbed and self-contained eye wash equipment shall deliver flushing fluid to the eyes at a flow rate not less than 1.5 litres per minute for a minimum of 15 minutes. Where the fluids supply to plumbed equipment is time-limited, this shall be clearly indicated and quantified by prominent signage adjacent to the equipment.
Where eye wash equipment has a time-limited supply of flushing fluid, a risk assessment shall be conducted to identify whether a longer flow period is required. Such a risk assessment may address the nature and quantity of hazardous materials at the location, likely exposure scenarios, distance to emergency response and emergency facilities and so on.
Appendix F1 Personal Eyewash Units
The first seconds following an eye injury are often critical to keeping eye injury to a minimum. A personal eye wash may be kept in the immediate vicinity of employees working in a potentially hazardous area. The main purpose of these units is to supply immediate flushing. With this accomplished, the injured individual should then proceed to a plumbed or self-contained eye wash and flush the eyes for the required 15 minutes.