Unshielded Radiant Heat Sources
Hazard [Health Devices Nov 1983;13(1):27-8]
A member hospital reported that heat radiating from an infant warming lamp
caused two nearby compressed air hoses to burst. Although a patient was in an incubator
below the warming light at the time of the incident, no injury occurred. However, the
reporting hospital expressed concern that a fire could result if such a rupture occurred
in an oxygen hose.
The warming lamp involved was a gooseneck fixture that uses two 250-watt
bulbs with reflective metal backing. The hoses, which were connected to overhead
compressed air outlets and were supplying air to an O2 blender and ventilator,
were inadvertently draped close to these bulbs. We created a similar setup in our
laboratory and tested hose samples identical to those that ruptured to determine whether
the hoses burst due to heat radiating from the bulbs or from contact with the hot lamp.
Within two minutes of placing a hose 2.5 cm from a hot lamp, the hose softened, developed
a bulge on the side facing the lamp, and finally burst loudly. Placing the hose in direct
contact with the lamp caused it to melt and rupture. Since there was no evidence of
melting on the hoses in the reported incident, we believe that radiant heat caused the
hoses to rupture.
To assess the potential for a fire resulting from such a rupture, we
substituted oxygen pressurized at 55 psi for the compressed air. As before, the hose
softened and burst when exposed to radiant heat, but did not spontaneously ignite. While
this may suggest that the chance of fire is minimal, combustible objects near the point of
rupture (and, thus, close to the lamp) or hoses of more combustible composition from other
manufacturers could be ignited in an oxygen-enriched atmosphere.
While the reported incident involved a specific model of infant warming
light, most perinatal and general-use heat lamps are of the gooseneck style and pose
similar risks. Very often, bulbs and other hot surfaces (e.g., metal reflectors) are not
adequately shielded, resulting in increased risk of damage to the bulb as well as burns to
personnel (especially during close procedures) and equipment damage.
- Keep hoses, as well as electric cords and patient
leads, and other flammable objects (e.g., drapes, towels) away from any heat
source. This is especially important for hoses carrying
combustion-supporting gases (e.g., oxygen, nitrous oxide).
- Avoid using radiant heat lamps that lack protective
shields. Such lamps are easily damaged and can burn personnel or damage
other equipment. Lack of protective shielding also increases the risk of
igniting nearby flammable objects.
- Hospitals that own radiant heat lamps without protective shielding
should contact the manufacturer to see if modifications are available.
- Warmers, Radiant, Infant [13-249]
- Warmers, Radiant, Infant, Mobile [17-433]
- Warmers, Radiant, Infant, Stationary [17-956]
- Warmers, Radiant, Infant, Transport [13-251]
Cause of Device-Related Incident
Device factor: Device interaction
User error: Incorrect clinical use
Mechanism of Injury or Death
Failure to deliver therapy; Fire; Suffocation