Tony Constable, sales and marketing manager of Autron Products which makes LST radiators, discusses the challenges facing the commercial-heating sector
WITH the cost of heating rising, the pressure on facility managers to meet the varied needs of all tenants can be a challenge.
And, with local authorities' energy targets being ratcheted
down, and energy prices going up, it is vital that in specifying the appropriate heat source the system offers efficiency, controllability and safety.

Radiators are an efficient means of distribution, but standard panel radiator surfaces can reach up to 70˚C - 80˚C emitting between 20% and 50% of the output by radiated heat.
Children and the elderly have a risk of burns even at lower temperatures because of their skin thickness, so a low-surface-temperature (LST) radiator should be installed.

Duty of care

LST radiators emit almost 100% of the output by convection. Heat circulates around the room efficiently, limiting the surface temperature of the casing.

The relevant design criteria for LST radiators states the maximum casing surface temperature should not exceed 43˚C, a benchmark established by the NHS guidance notes, the DDA, DfeS BB87, BS8300 and others.

Social service agencies and Help the Aged have previously recommended the fitting of LST covers over existing radiators to enable and protect a vulnerable person in their home.
With litigation a real possibility, this is one risk assessment that should be taken seriously.

The fact that ordinary panel radiators are used in most domestic dwellings is no defence - ignorance is not an excuse. And anyone who provides a facility for the purpose of another has a duty of care over those who use it, especially those who are considered to be at risk.
Putting a warning label on a hot surface merely acknowledges the risk and the liability for any potential claims.

There are two types of LST radiators: those which are a cover for a standard panel radiator and those which are designed with an energy-efficient finned-tube
emitter.

However, the former LST radiator consists of a panel radiator behind a cover. But BSRIA testing confirms that, while the side and front reaches no higher than 43˚C, the top outlet grille can reach temperatures up to 59˚C - which could still burn a child.

Purpose-designed finned tube type LST radiators do not reach these unacceptable levels.

Modern LST radiators which use finned-tube emitters mounted in the lower part of a casing can be designed to offer an enhanced output but with a lower flow temperatures, by increasing the number of tubes within the same casing.

This design maintains the LST criteria including the outlet grille, while the finned-tube emitters can be easily adapted for applications where the outside air is induced below the emitter to temper the temperature of fresh air.

Most LST radiators heat by convected air and therefore those with finned-tube style emitters can be easily designed into corner units or recessed into an alcove.

The heating system with finned-tube emitters has a positive displacement of water, is responsive to control by temperature regulating valves and consequently heat a room quickly, saving energy.

Standards needed

However, there is no British or European standard for the design of LST radiators. Without a recognised standard, it is only a matter of time before a local authority or social-housing provider is sued for a lack of care and attention.

Both types of LST radiator have a place in social housing improvements and it is generally accepted that either design is better than using standard panel radiators.

Recently, a private retirement home was fined a sum of £30,000 for using radiator guards that did not prevent a resident from suffering fatal burns when she fell against the radiator.

Autron Sales: Tel 01787 473964 or e-mail sales@autron.co.uk