Return to work

Disinfecting The Workplace

Katy Welch HSE, Return to work, Risk Assessment , , , , ,
Disinfecting The Workplace

Disinfecting Premises Using Fog, Mist, Vapour or Ultraviolet (UV) Systems During the Coronavirus Outbreak

The HSE has issued this guidance. It notes that, during the coronavirus (COVID-19) outbreak, fog, mist, vapour or UV treatments may be suitable options to help control the spread of the virus, by cleaning and disinfecting a larger space or room. Any use of these treatments for these purposes should form part of the COVID-19 risk assessment. Users must be competent and properly trained.

Selecting the correct treatment will depend on:

  • the size of the area to be treated, its shape and how easily it can be sealed off if delivering an airborne product
  • whether there are hard or soft surfaces – soft furnishings may act as a ‘sink’ for the airborne chemicals and emit them for some time after treatment (it may be possible to remove items such as sofas before treatment)
  • the type of business you have – some areas may be better suited to UV surface treatments than airborne chemicals or vice-versa.

Avoiding harm

Disinfectants applied as a fog, mist or vapour may reach harmful levels during delivery and UV systems may cause eye/skin damage if people enter an area undergoing treatment. Discuss with suppliers what safety features they can provide to prevent inadvertent access to a room during treatment. For example, safety sensors, simply locking rooms during treatment if feasible, or safety signage as part of a safe system of work.

The guidance says:

  • do not spray people with disinfectant
  • do not disinfect large outdoor spaces.

Ensure that you follow the manufacturer’s instructions to ensure you are using the product safely and effectively. Advice on the law on chemicals is set out.

The guidance goes on to cover sealing off rooms – which is necessary to avoid risk of human exposure to the potentially harmful treatments. Disinfectants may reach harmful levels during delivery and UV systems may cause eye/skin damage if people enter an area undergoing treatment. It suggests that rooms that are very difficult to seal may not be suitable for delivering airborne chemicals.

Source: Barbour 2020

Screening Employee’s… What’s your best option?

Katy Welch Return to work , , ,
Back to work

With many workplaces beginning to re-open or have gradual phased return to work the question is which technology, if any, do you use to assess infection in returning staff?

Many companies have opted to use temperature and moreover an abnormal rise in ‘core’ temperature to highlight possible cases of COVID-19.

If you are going to use temperature as a guide then you should be aware of the shortcomings so we’ve used peer reviewed evidence to give you the information you need.

So… what is normal ‘core’ temperature? The reality is, there isn’t one exact “normal” body temperature, so be prepared for a range of “normal”. However, the NHS consider a fever is usually when your body temperature is 37.8 C or higher.

Measurement of core temperature, if you want to be super accurate is best done using pulmonary artery catheterization as it is the reference standard to measure core body temperature, however we would not suggest you use this in the workplace…. “don’t do this at home folks”. Then of course there is the use of rectal and oral thermometers, which moderately correlates to core temperature but is also a tad invasive.

The tympanic (in your ear) infra-red thermometer frequently used in patient care has been shown to correlate with core body temperature and could be self administered to adhere to distancing guidance.

Handheld cutaneous (skin) infra-red thermometer is popularly used to screen large numbers of individuals due to it’s portability and that it does not require contact or cause discomfort to the individual being assessed, however there is little data to support its use.

Among common cutaneous infra-red thermometers evaluated for their ability to measure temperature traceable to the International Temperature Scale of 1990 (ITS-90), the majority performed outside the accuracy range stated by the manufacturers and the medical standard. (Fletcher et al 2018).

The handheld cutaneous infra-red thermometer was less accurate than the tympanic thermometer and other infra-red thermal systems for temperature measurements and fever detection. (Bijur et al, 2016, Lui et al, 2004, Hausfater et al, 2008 and Tay et al 2015).

The study by Tay et al 2015, showed that the handheld infra-red thermometer had a low sensitivity of 29.4% when compared with the oral thermometer to detect fever.

The performance of the hand held cutaneous infra-red thermometer is operator-dependent, as the thermometer is aimed at the temple or forehead, and distance between the thermometer and skin may affect its accuracy. It is not unlikely that sub-optimally trained operators, shying away from close contact with those being screened, hold the thermometer further away than the required proximity and thus compromise its effectiveness.

In a pandemic, a false negative is a false reassurance and a potential future infection cluster (Aw, 2020)

Information taken from The Journal of Hospital Infection.

AW, J. 2020. The non-contact handheld cutaneous infra-red thermometer for fever screening during the COVID-19 global emergency. The Journal of hospital infection, 104, 451-451.