NHS Heatwave Thermometer Buyer’s Guide
The NHS Heatwave Thermometer Buyer's Guide will help you to purchase the appropriate equipment in order to satisfy the requirements of the NHS Heatwave plan.
The NHS Heatwave for England plan is a set recommended procedures to be used in the event of a period of very hot weather.
A wide range of thermometer equipment is available and this document will take you through the pros and cons of each option.
Heatwave Plan Requirements
When a heatwave code RED is declared in accordance with the NHS Heatwave plan, it is recommended that all areas with patients should be kept below 26°C.[i]
“ensure that cool rooms are consistently below 26ºC as this is the temperature threshold at which many vulnerable patients find it difficult to cool themselves naturally if sweating is impaired due to old age, sickness or medication”
In addition, the Heatwave Plan recommends that the temperature in cool areas should be measured four times per day to ensure the temperature remains below the 26°C threshold.
“check that indoor temperatures are recorded four times a day for all areas with patients in”
The big question is, when a code RED alert is declared, how should you check and record the temperature to ensure it doesn’t go over the 26ºC threshold?
Heatwave Monitoring Solutions
A wide range of solutions are available to solve the measurement requirement, ranging from simple manual systems to very sophisticated automated systems.
In order to conform with the Heatwave plan only a simple manual system need be implemented when a code RED has been declared.
You may wish to implement a more sophisticated temperature monitoring and alerting system as a part of your facilities management plan. The efficient use of power in your air conditioning and central heating is very much on the agenda at the moment and the two systems could be linked.
Manual Temperature Monitoring Solutions
The measurement and recording requirement, according to the Heatwave Plan, is that the temperature should be measured and recorded four times per day whilst a code RED is in effect.
The simplest solution would be to equip a person designated as the data collector with a handheld digital thermometer with an air thermometer and a clip board to record the temperatures.
It is worth bearing in mind when purchasing the temperature probe how long the response time is. The response time specifies how long the probe takes to adjust to the ambient temperature in the room. A long response time could have one of two results:
- Inaccurate temperature readings because the data collector did not wait for the probe to adjust properly to the room temperature; or
- Wasted time as the temperature probe adjusts to the ambient temperature.
One solution that would avoid the sensitivity problem would be to place the thermometer in the room being measured for the duration of the code RED alert.
A wall mounted analogue thermometer would be at the ambient room temperature and would display the value. The data recorder would then simply have to read the temperature from the display and record the value in an appropriate way.
More sophisticated wall mounted thermometers are available that not only have a visual readout of the current temperature but can produce a paper based log. The data recorder would then only need to retrieve the paper log from the thermometer periodically, say once per day, and store the log for auditing purposes.
A paper based log would reduce the time burden on the data collector significantly.
There are a number of problems with manually recording the temperature:
- Data collection is unlikely to be a full time job, so it may well be forgotten in the hustle and bustle of other duties;
- During a heat wave temperatures may rise quickly between temperature measurements leaving vulnerable patients potentially at the mercy of high temperatures. Precisely the situation that the Heatwave Plan is intended to remedy;
- Rooms on different elevations may heat and cool at substantially different rates. Measuring the temperature in one room doesn’t necessarily give an indication of temperatures in another room. Southern facing rooms are likely to heat up faster than northerly facing ones especially when the windows are not shaded or don’t have reflective glass;
- People generate heat whether they are active or not. Rooms that have a number of people within them warm faster than unoccupied rooms especially when some of the occupants are busy working. A typical occupant would generate 400 British Thermal Units (BTU) of heat.
Automated Temperature Monitoring Solutions
One way to overcome the problems with manual temperature monitoring is to automate it. Automated systems don’t forget to record the temperature and they operate twenty four hours per day.
The downside is that they tend to cost more than manual systems. Though you may be pleasantly surprised at how little they do cost.
Any automated system must have the capability to alert appropriate staff to any breach in temperature of the 26ºC threshold.
The simplest automated systems available are data loggers. Most data loggers do not have an adequate alerting system built in but some of the more specialist units are able to make telephone calls when the temperature goes outside acceptable bounds.
The main limitation of a data logger is that a data logger needs to be placed into each room requiring temperature logging.
Whilst data loggers are not particularly expensive finding a phone socket for the phone dialler in each room may be a problem.
In addition, managing a number of data loggers spread around your campus may well prove to be time consuming. A data logger will log the temperature readings in each room. Unfortunately, the log is stored inside the data logger itself and would need to be retrieved from the data logger via a PC if you need to maintain a comprehensive temperature log.
So, a data logger based solution wouldn’t be completely automated.
One step up from a data logger would be a network based environmental monitoring system.
The environmental monitoring system would enable the collection and alarming to be performed from a single central system.
Each room in the hospital that must be monitored would require a temperature probe. The temperature probe could use the structured cabling running throughout your building.
A single unit then periodically records the temperature readings and alarms via email/SMS or strobe light when the temperature threshold is breached.
One major plus for automated systems is that not only can they monitor the room temperature but the more capable systems can also monitor the systems designed to regulate room temperature like your air conditioning and heating systems.
A failure of your air conditioning system in a cool room is likely to lead to rapid heat gain especially if it is on a southerly elevation. Automated systems, like the AKCP product line, can monitor the dry contact on the air conditioner and alert you to any failures.
You could also expect your environmental monitoring system to provide network mapping. Temperature mapping is a picture of your building with the real time temperature readings displayed in the location that the temperature logging is taking place.
Temperature mapping gives a great way to display any problems very quickly, especially when displayed on a large monitor so that the temperature information.
Temperature mapping gives an operation centre a great centre piece so that everybody can see precisely what the current state of play is.
Calibration
Any measurement equipment is required to be calibrated every year according to ISO quality standards.
If you are required to calibrate your temperature measurement equipment installed in order to conform to the Heatwave Plan then any system put in place must take calibration into account.
Fortunately, any system installed does not need to run 24/7/365 so onsite calibration is not required.
Many thermometers are sold with a manufacturer’s certificate of calibration. The certification will last a single year and needs to be renewed each year.
Your own quality system may specify a specific calibration standard that must be adhered to such as UKAS. In which case, you will need to purchase thermometers and UKAS calibration as an extra cost item. Each year when the thermometers are not in use you will need to re-calibrate your thermometers to the UKAS standard.
Any system you decide to commission needs to take into account yearly re-calibration and especially the extra cost element over the lifetime of the system.
Facilities Management Integration
Facilities management is the control, maintenance and supervision of the fabric and facilities provided by and within your built environment.
A modern hospital contains a number of complex systems for maintaining the temperature at a level appropriate for both patients and health workers.
Systems like air conditioning and central heating boilers are highly complex machines that do occasionally break down.
When a system as critical as both air conditioning or heating breaks down it can cause considerable disruption to the medical functioning of a hospital.
In all probability any breakdown will occur when the system in question is under the heaviest use. So, a breakdown of your air conditioning is far more likely to occur during a heat wave than during the depths of winter and likewise the central heating boiler is most likely to fail during a hard winter.
Whilst monitoring won’t stop a failure from happening it will alert you to the failure more quickly than relying on service users to inform you of a failure, giving you more time for you take remedial action to mitigate the problem.
Many systems used in facilities management provide a means to detect system failure. Devices typically provide one or more dry contact ports that can be monitored to detect failure.
A number of environmental monitors provide a way to quickly and easily monitor dry contact ports for failure and alert you when things go wrong.
Many environmental monitors can interface with your existing alarm system using a dry contact port as input.
In addition, environmental monitors are also able to monitor temperature and humidity levels in a number of locations often utilising your existing structured cabling.
Summary
| Approach | Analog Thermometer | Digital Thermometer | Data Logger | Environment Monitor |
| Logging Method | Manual | Manual | Partially Automated | Fully Automated |
| Alerts | None | None | Alarm indication on unit | Automated – email/SMS/alarm integration |
| Cost | Low | Low | Medium | Medium/High |
References
HEATWAVE PLAN FOR ENGLAND 2008 PROTECTING HEALTH AND REDUCING HARM FROM EXTREME HEAT AND HEATWAVES
Gateway reference: 9575
Glossary
Thermometer
A device for measuring temperature though some models also combine relative humidity as well.
Analog thermometer
A simple thermometer that measures and displays the temperature using a simple dial.
Digital thermometer
A digitally controlled thermometer giving greater accuracy than an analog thermometer with a LED or LCD display. More functional digital thermometers include features like min/max readings and limited memory recall
Data logger
A thermometer designed to log temperature values over an extended period usually using battery power. Blind data loggers have no display capability though for a small premium units with a LCD display are available. Some data loggers are available with rudimentary alerting capabilities. All data loggers have some mechanism for connecting to a PC so that the temperature readings can be downloaded for storage and analysis purposes.
Environmental Monitor
An environmental monitor is a fully featured system capable of monitoring a number of different environmental conditions like temperature, humidity, wetness, smoke, dry contact, power presence/power meter and so on. Environmental monitors are completely stand alone devices that can record and alarm without external intervention. The more sophisticated environmental monitors are capable of complex visualization such as temperature maps.
