CSA Z23500-2-2020 pdf free download

CSA Z23500-2-2020 pdf free download.Preparation and quality management of fluids for haemodialysis and related therapies Part 2: Water treatment equipment for haemodialysis applications and related therapies
(ISO 23500-2:2019, MOD).
to prevent water containing chlorine or chloramine trom entering the teed water line of downstream purification devices, such as reverse osmosis, while the carbon beds are being backwashed. For carbon beds that are backwashed automatically on a time schedule, the face of the timers used to control the backwash cycle should be visible to the user and the timer should be set so that backwashing occurs when dialysis is not being performed.
In some instances, activated carbon might not provide adequate removal of chiorarnine. Inadequate removal of chloramine can occur when the pH of the water is high, or when municipal water contains high levels of organic material or additives, such as orthophosphate for lead and copper control. Inadequate removal of chloramine can also appear to occur when naturally-occurring N-chlorarnines are present in the water. N-chlorarnines are relatively large molecules and are removed by reverse osmosis; however, they test positive in the assays used for chloramine, thus giving the impression of inadequate chloramine removal,
In these circumstances, other strategies for chioramine removal might be needed. One approach that has been used successfully is the injection of sodium bisuiphite prior to the reverse osmosis system. Other approaches include installing anion exchange resin before the carbon beds to remove organic matter and other contaminants that might foul the activated carbon, or the injection of a mineral acid before the carbon beds to reduce the p1-I of alkaline feed water.
If carbon beds fitted with an online monitor for measuring total chlorine in the product water are used. there should be a means of preventing patient exposure to unsafe product water, such as the diversion of the product water to drain or a system shutdown, should the total chlorine level in the product water exceed 0,1 mg/I. Accompanying visual and/or audible alarms shall meet the relevant requirements of IEC 60601-1-8; for low-priority alarms If product water is diverted to drain or the system is shut down; otherwise, the alarms shall meet the relevant requirements of IEC 60601-1.8 for high priority alarms.
In addition, the sound emitted by the audible alarm shall be at least 65 d13 (A” scale) at 3 m and it shall not be possible to silence the alarm for more than 180 s. Alarms shall be situated so that they ensure a prompt response by personnel in the patient care area.
If the online monitor is placed between two carbon filters in series, a low-priority alarm can be accepted as long as manual surveillance is performed after the last filter or bed in the event of an alarm.
4.2.9 ChemIcal Injection systems
Sodium bisuiphite injected into the source water can be an effective means of reducing chlorine and chiorarnine concentrations. Ascorbic acid has also been used for this purpose. In addition, reducing the pH of alkaline feed water by the injection of mineral acids can enhance the efficiency of granular activated carbon. Chemical injection systems shall include a means of regulating the metering pump to control the addition of chemical. This control system shall be designed to tightly control the addition of chemical. The control system shall ensure that chemical is added only when water is flowing through the pre-treatment cascade and that it is added in fixed proportion to the water flow or based on some continuously observed parameter, such as pH. using an automated control system. If an automated control system Is used to inject the chemical, there shall be an Independent monitor of the controlling parameter. Monitors shall be designed so that the monitor cannot be disabled while a patient is at risk, except for brief, necessary periods of manual control with the operator in constant attention.CSA Z23500-2-2020 pdf free download.