Treatment tabletops are usually made of carbon fibre due to its high mechanical strength and rigidity, low specific density, extremely light and regularly considered radiotranslucent. Our clinic acquired a Calypso 4D Localization System where electromagnetic (EM) frequencies to detect implanted transponders in the patient are used. Carbon fibre is an electrical conductive material which interferes with EM frequencies. Therefore, in order to be able to use the Calypso System the carbon fibre tabletop in the treatment room must be replaced. It is our goal to determine the attenuation of the new, non-carbon fibre, tabletop in treatment delivery.

Measurements were performed using an ionisation chamber inserted in a slab phantom positioned at the isocenter for 6, 10 MV, 6 and 10flattening filter free (FFF) MV photon beams. These measurements were performed with and without tabletop for 0°, 30° and 60° beam angle for a True Beam STx linac, for 5×5 cm2 and 10×10 cm2 field size beams. The attenuation was calculated for each measurement for each tabletop.

At 0° incidence on the Exact IGRT Couch, the measured attenuation for 10×10 cm2 was 2·8 and 2·1% for 6 and 10 MV beams, respectively. For the same field size was measured 3·3 and 2·6% attenuation for 6 and 10 FFF MV beams, respectively. At the same incidence and regarding the other tabletops, the calculated attenuation is lower. For 10×10 cm2 field, there is 2·0, 1·4, 2·1 and 2·6% attenuation for 6, 10 MV, 6 and 10 FFF MV energy beams on the kVueTM Universal Couch. For the KvueTM Calypso® Couch 10×10 cm2 irradiation field, the measurements were 1·6, 1·3, 1·9 and 1·5%, respectively. This tendency is observed for all gantry angles.

The attenuation outputs were definitely higher for the Varian Exact IGRT Couch when compared with the kVue tabletops. The attenuation measurements for the kVue tabletops were closer to each other. Nevertheless kVueTM Calypso® Varian tabletop showed smaller mean attenuation of the beams than kVueTM Universal Tip Insert for all measurements.

There was no loss in treatment quality administration due to beam attenuation in the tabletop when tabletops were exchanged because of Calypso system integration. There is no need to change between kVue tabletops whenever there is a regular treatment or a Calypso System guided treatment.

We aimed to develop and test a community resilience tabletop exercise to assess progress in community resilience and to provide an opportunity for quality improvement and capacity building.

A tabletop exercise was developed for the Los Angeles County Community Disaster Resilience (LACCDR) project by using an extended heat wave scenario with health and infrastructure consequences. The tabletop was administered to preparedness only (control) and resilience (intervention) coalitions during the summer of 2014. Each exercise lasted approximately 2 hours. The coalitions and LACCDR study team members independently rated each exercise to assess 4 resilience levers (partnership, engagement, self-sufficiency, and education). Resilience coalitions received more detailed feedback in the form of recommendations for improvement.

The resilience coalitions performed the same or better than the preparedness coalitions on the partnership and self-sufficiency levers. Most coalitions did not have enough (both quantity and type) of the partner organizations needed for an escalating heat wave or changing conditions or enough engagement of organizations representing at-risk populations. Coalitions also lacked educational materials to cover topics as far ranging as heat to power outages to psychological impacts of disaster.

A tabletop exercise can be used to stress and test resilience-based capacities, with particular attention to a community’s ability to leverage a range of partnerships and other assets to confront a slowly evolving but multifactorial emergency. (Disaster Med Public Health Preparedness. 2015;9:484–488)