X-ray tube operators can be exposed to equal or higher scattered radiation doses to the hand as cassette holders during diagnostic radiographic procedures of the equine vertebral column and limbs.

OBJECTIVE: The objectives of this study were to investigate scattered radiation doses to the hands of equine workers holding the cassette and the x-ray tube by hand, for both limb and vertebral column studies, and to compare the scattered radiation attenuation of lead with radiation protection lead-free gloves. Radiation doses to the hands of the cassette holder in the primary beam were also investigated. SAMPLE: A whole-body horse cadaver. PROCEDURES: A portable x-ray unit was used to simulate 6 radiographic study types in the horse cadaver. Doses were measured with no shielding and, for cassette holders, with the ion chamber enclosed in a lead glove and a lead-free glove. Thirty exposures were performed for each study view and condition (n = 1,920). RESULTS: Mean scattered doses to x-ray unit operators were higher than doses to cassette holders for ungula (hoof), thoracic vertebrae, and lumbar vertebrae studies, whereas doses to cassette holders were higher than doses to x-ray tube operators for studies of the metacarpophalangeal joint (fetlock) and tarsus (hock). Doses did not differ for the stifle joint. Mean percentage decrease in scattered radiation dose was 99.58% with lead gloves and 98.9% with lead-free gloves. CLINICAL RELEVANCE: X-ray tube operators can be exposed to equal or higher scattered radiation doses to the hand as cassette holders. Lead-free hand shielding should only be considered as an alternative to lead gloves if their lighter weight increases frequency of use by workers.

Workers should take steps to mitigate surface lead exposure when using lead-containing personal protective equipment.

Veterinary workers use lead shielding for protection against harm from ionizing radiation during diagnostic imaging. Surface lead on shielding has been reported as a potential exposure hazard. The purpose of this prospective, analytical, descriptive study was to measure surface lead on lead-containing shielding in the field service and small animal radiology areas of a veterinary teaching hospital, and to examine potential risk factors for surface lead. Surface lead on a convenience sample of 54 lead shielding items was measured in a commercial laboratory using inductively coupled plasma mass spectrometry. The median and range of surface lead for aprons, thyroid collars, and gloves were 3.6 µg/dm2 (range, 1.3-22.4 µg/dm2 ), 23.1 µg/dm2 (range, 2.6-116 µg/dm2 ), and 134 µg/dm2 (range, 1.5-155 µg/dm2 ), respectively. In the final multivariable analysis, the mean surface lead on thyroid collars and gloves was higher than on aprons (relative differences 4.8, 95% confidence interval [CI] 2.2, 10.5, P < 0.001; and 9.5, 95% CI 4.4, 20.6, P < 0.001, respectively). The mean surface lead on shielding in the worst condition was higher than on shielding in the intermediate and best conditions (P < 0.001). Lead shielding provides effective protection against the harmful effects of ionizing radiation, and shielding should always be worn during radiation exposure. Based on our findings and the common use of lead shielding in veterinary workplaces, we recommend that employers inform workers of this hazard and provide training on steps to mitigate exposure, including the use of disposable gloves when wearing lead shielding and handwashing after use.

Survey of self-reported radiation safety practices among North American veterinary technicians involved in equine radiography using portable x-ray equipment.

OBJECTIVES: To describe self-reported radiation safety practices by equine veterinary technicians in North America and identify factors associated with these practices. SAMPLE: 154 equine technicians. PROCEDURES: An electronic questionnaire regarding radiation safety practices during the use of portable x-ray equipment was sent to 884 members of the American Association of Equine Veterinary Technicians and Assistants. Data were summarized, and various factors were evaluated for associations with reported safety practices. RESULTS: 221 of 884 (25.0%) questionnaires were completed, including 154 by equine technicians who had been involved in equine radiography as x-ray tube operators, cassette holders, or both in the previous year. Lead apron use was suboptimal, reported as "always" for 80.0% (104/130) of tube operators and 83.1% (123/148) of cassette holders. Approximately 20% of participants never wore thyroid shields, and approximately 90% never wore lead eyeglasses. Almost 50% of participants did not have lead eyeglasses available. Although > 55% of participants always held the x-ray equipment by hand, 58.4% (73/125) of tube operators and 25.0% (35/140) of cassette holders never wore gloves. Cassette holders wore lead gloves and personal radiation dose-monitoring devices significantly more frequently than did tube operators. CONCLUSIONS AND CLINICAL RELEVANCE: Compliance of North American equine technicians with radiation safety recommendations by the National Council on Radiation Protection and Measurements was suboptimal. Improvements in radiation safety training and education, strengthening the connection between academic institutions and private practices, and greater availability and requirement of personal protective equipment use by senior clinicians and employers might aid in improving safety practices.

Self-reported radiation safety behaviors among veterinary specialists and residents performing fluoroscopic procedures on small animals.

OBJECTIVE: To describe the radiation safety behaviors of veterinary specialists performing small animal fluoroscopic procedures and examine potential risk factors for these behaviors, including knowledge of radiation risk and training regarding machine operating parameters. SAMPLE: 197 veterinary specialists and residents in training. PROCEDURES: An electronic questionnaire was distributed to members of the American Colleges of Veterinary Internal Medicine (subspecialties of cardiology and small animal internal medicine), Veterinary Radiology, and Veterinary Surgery. RESULTS: The overall survey response rate was 6% (240/4,274 email recipients). Of the 240 respondents, 197 (82%) had operated an x-ray unit for a small animal fluoroscopic procedure in the preceding year and fully completed the questionnaire. More than 95% of respondents believed that radiation causes cancer, yet approximately 60% of respondents never wore hand or eye protection during fluoroscopic procedures, and 28% never adjusted the fluoroscopy machine operating parameters for the purpose of reducing their radiation dose. The most common reasons for not wearing eye shielding included no requirement to wear eyeglasses, poor fit, discomfort, and interference of eyeglasses with task performance. Respondents who had received training regarding machine operating parameters adjusted those parameters to reduce their radiation dose during procedures significantly more frequently than did respondents who had not received training. CONCLUSIONS AND CLINICAL RELEVANCE: On the basis of the self-reported suboptimal radiation safety practices among veterinary fluoroscopy users, we recommend formal incorporation of radiation safety education into residency training programs. All fluoroscopy machine operators should be trained regarding the machine operating parameters that can be adjusted to reduce occupational radiation exposure.

Radiation safety practices among Canadian equine veterinary workers during diagnostic procedures with portable X-ray equipment.

The objective of this study was to report observed radiation safety practices among equine workers using portable X-ray units at 3 veterinary practices in Canada. Practice 1 was comprised of equine field service workers from an academic institution, whereas Practices 2 and 3 were comprised of workers from private equine referral practices. Out of 2969 exposure-worker observations, protective aprons were worn for > 99% (2968/2969), thyroid shields for 87% (2584/2969), and eyeglasses for 10% (310/2969). The cassette was held by hand for 97% (1078/1114) of observations, and the X-ray unit was held by hand for 100% (1293/1293) of observations. Gloves were used for 54% (606/1114) and < 1% (5/1293) of observations involving cassette holders and X-ray tube operators, respectively. Use of gloves was more frequent among technologists than DVMs (P = 0.004), and among workers in Practices 1 and 3 than in Practice 2 (P < 0.001). In conclusion, given that workers commonly hold cassettes and X-ray tubes by hand, improvement in shielding use is needed. Consideration should be given to specific behavior recommendations in radiation regulations.

Pratiques de radioprotection chez les travailleurs vétérinaires équins canadiens pendant les procédures de diagnostic avec un équipement de radiographie portable. L'objectif de la présente étude était de rapporter les pratiques de radioprotection observées chez les travailleurs équins utilisant des appareils de radiographie portatifs dans trois pratiques vétérinaires au Canada. La pratique 1 était composée de travailleurs équins sur le terrain d'une institution universitaire, tandis que les pratiques 2 et 3 étaient composées de travailleurs sur le terrain issus de pratiques de référence équines privées. Sur 2969 observations de travailleurs exposés, des tabliers de protection ont été portés pour > 99 % (2968/2969), des écrans thyroïdiens pour 87 % (2584/2969) et des lunettes pour 10 % (310/2969). La cassette a été tenue à la main pour 97 % (1078/1114) des observations et l'unité de radiographie a été tenue à la main pour 100 % (1293/1293) des observations. Des gants ont été utilisés pour 54 % (606/1114) et < 1 % (5/1293) des observations impliquant des porteurs de cassette et des opérateurs de tubes à rayons X, respectivement. L'utilisation de gants était plus fréquente chez les technologues que chez les vétérinaires (P = 0,004) et chez les travailleurs des Pratiques 1 et 3 que ceux de la Pratique 2 (P < 0,001). En conclusion, étant donné que les travailleurs tiennent généralement des cassettes et des tubes à rayons X à la main, une amélioration de l'utilisation du blindage est nécessaire. Il faudrait tenir compte des recommandations de comportement spécifiques dans les réglementations relatives aux rayonnements.(Traduit par Dr Serge Messier).

A 7-min video training intervention improves worker short-term radiation safety behavior during small animal diagnostic radiography.

Although manual restraint for small animal diagnostic radiography is common, worker protection is often not optimized, particularly for hands and eyes. Radiation safety training videos generally include hours of material on content other than personal protective equipment (PPE), have limited content, if any, on reducing dose to the lens of the eye, and are presented at the level of veterinary professionals. The objectives of this prospective, observational study were to develop a short, open access video training intervention at the layperson level, focused on proper use of PPE, and to test the effectiveness of the training video in changing behavior of workers. The use of PPE, optimal head position, and body position relative to the source of scattered radiation were compared before and after the video training was completed by workers. Results of unconditional and multivariable analyses were similar. In final multivariable analysis, workers wore gloves correctly more frequently (odds ratio [OR] = 2.09; 95% confidence interval [CI], 1.68-2.59; P < .001) and wore eyewear more frequently (OR = 1.85; 95% CI, 1.23-2.78; P = .003) after completing the training intervention. Workers also had an optimal head position more frequently (OR = 1.27; 95% CI, 1.03-1.58; P = .03) and stood straight or leaned back more frequently (OR = 1.85; 95% CI, 1.48-2.23; P < .001) after completing the training. The video training developed in this study is an effective tool that can be incorporated into a radiation protection program to improve worker radiation safety behaviors during manual restraint for small animal diagnostic radiography.

Effect of full versus open-palm hand shielding on worker radiation dose during manual restraint for small animal radiography.

Open-palm hand shields are used by veterinary workers during manual restraint for small animal radiography. The objective of this study was to measure the reduction in scatter and primary beam radiation dose to the hand provided by a full glove and an open-palm shield, using a cadaver dog to simulate restraint by 2 workers of an awake, cooperative patient undergoing thoracic and abdominal radiography. Dose was measured for 30 exposures for each condition, for a total of 795 exposures. The mean percentage decrease in scatter radiation dose was 99.9% for a full glove and 40% for an open-palm shield. The mean percentage decrease in primary beam radiation dose was 98.4% for a full glove. To optimize worker protection, fully enclosing gloves should be used during manual restraint for radiography, and body parts should never be placed in the primary beam, even when shielded.

Des protecteurs à paume ouverte sont utilisés par le personnel vétérinaire pour la contention manuelle des animaux de compagnie lors de radiographie. L'objectif de la présente étude était de mesurer la réduction de radiation du faisceau primaire et de rayonnement de dispersion du faisceau fournie par un gant complet et un protecteur à paume ouverte, en utilisant un cadavre de chien pour simuler la contention par deux employés d'un patient coopératif soumis à des radiographies thoracique et abdominale. La dose fut mesurée pour 30 expositions de chaque condition, pour un total de 795 expositions. Le pourcentage moyen de diminution de radiation du rayonnement de dispersion du faisceau était de 99,9 % pour le gant complet et de 40 % pour le protecteur à paume ouverte. Le pourcentage moyen de diminution de radiation du faisceau primaire était de 98,4 % pour le gant complet. Afin d'optimiser la protection des employés, des gants complets devraient être utilisés durant la contention manuelle pour les radiographies, et des parties du corps ne devraient jamais être dans le faisceau primaire, même si elles sont protégées.(Traduit par Docteur Serge Messier).

Use of protective hand shielding by veterinary workers during small animal radiography.

Federal government guidelines recommend wearing hand shielding that provides full protection for the entire hand during manual restraint of animals for radiography. The primary objective of this cross-sectional survey of 143 Saskatchewan veterinary workers was to describe behaviors of workers who do not follow guidelines for effective hand shielding, and to examine the factors associated with these behaviors. An electronic invitation to complete an online questionnaire was sent to 1261 members of the provincial veterinary medical and veterinary technologist associations. More than half of the workers reported that their hand protection was visible on a radiograph at least once a month, and 1/5 reported visible unshielded body parts at least once a month. More than 1/3 of workers never used shielding that fully enclosed their hands. Use of fully enclosing gloves or mittens was more likely for workers in academic workplaces (P < 0.001).

Usage d'une protection pour les mains par les préposés vétérinaires durant la radiographie des petits animaux. Les lignes directrices du gouvernement fédéral recommandent le port d'une protection pour les mains qui offre une protection complète pour l'ensemble de la main durant la retenue manuelle des animaux lors de la radiographie. L'objectif primaire de cette enquête ponctuelle auprès de 143 préposés vétérinaires de la Saskatchewan consistait à décrire les comportements des préposés qui ne respectent pas les lignes directrices en matière de protection efficace des mains et à examiner les facteurs associés avec ces comportements. Une invitation électronique à répondre au questionnaire en ligne a été envoyée aux 1261 membres des associations provinciales de médecins vétérinaires et de technologues vétérinaires. Plus de la moitié des préposés ont signalé que leur protection était visible sur une radiographie au moins une fois par mois et 1/5 a signalé des parties du corps visibles non protégées au moins une fois par mois. Plus de 1/3 des préposés n'utilisait jamais une protection complète des mains. L'usage de gants ou de mitaines entièrement fermées était plus probable pour les préposés travaillant en milieu universitaire (P < 0,001).(Traduit par Isabelle Vallières).

Self-reported use of x-ray personal protective equipment by Saskatchewan veterinary workers.

OBJECTIVE To describe self-reported use of x-ray personal protective equipment (PPE) by veterinary workers in Saskatchewan, Canada, and to examine factors that affected their use of x-ray PPE. DESIGN Cross-sectional survey. SAMPLE 331 veterinary workers. PROCEDURES A questionnaire was distributed to Saskatchewan veterinary workers electronically and by conventional mail. Recipients were encouraged to share the questionnaire with colleagues. The questionnaire consisted of questions regarding radiation safety practices used during small animal radiographic procedures, including frequency of use of dosimeters and lead aprons, thyroid shields, eyeglasses, and gloves. Respondents were also requested to provide suggestions for increasing use of PPE. RESULTS 460 questionnaires were completed, of which 331 were returned by workers involved with performing radiographic procedures. Two hundred eighty-five of 331 (86%) respondents reported that at least 1 worker was always in the room during x-ray exposure, and 325 (98%), 291 (88%), and 9 (3%) respondents reported always wearing a lead apron, thyroid shield, and protective eyeglasses, respectively, during radiographic imaging. Two hundred seventeen of 327 (66%) respondents used lead gloves correctly less than half the time. Mean percentage of time that gloves were worn correctly was higher for workers who were required to do so by their employers than for those who were not. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested use of PPE during radiographic procedures can be increased by employers making PPE use mandatory. Other respondent-identified factors that would increase PPE use included the availability of properly fitting and functional PPE and education of workers about health risks associated with ionizing radiation exposure.

Use of personal protective equipment in a radiology room at a veterinary teaching hospital.

The use of personal protective equipment by veterinary workers during radiographic imaging is inconsistent. While the self-reported use of leaded aprons and thyroid shields approaches 100% in some studies, the use of leaded gloves and eyeglasses is much lower. Previous studies describing personal protective equipment use are based on self-reporting. Objectives of this prospective, observational study were to describe use of leaded personal protective equipment during radiographic imaging by veterinary workers, and to compare observed use with self-reported use. Use of leaded personal protective equipment during radiographic imaging by veterinary workers was observed over a 10 week period using two motion-triggered video cameras, and a questionnaire was then completed by workers on their use of personal protective equipment. Workers restrained the animal during 91.8% (753/820) of exposures. An apron and a securely closed thyroid shield were worn for >99% of studies. Gloves were used correctly for 43.6% (156/358) of radiographic studies. Leaded eyeglasses were worn for 1.7% (6/358) of studies. Correct glove use was more frequent during regular working hours than after-hours for both veterinarians (odds ratio 32.7, P = 0.001) and veterinary students (odds ratio 75.1, P < 0.001). The number of workers in the room was lower when animals were sedated (P = 0.002) or anesthetized (P = 0.017). Workers overestimated their frequency of glove use (P <0.001). In conclusion, workers use personal protective equipment less frequently in an unsupervised environment, and overestimate their use of personal protective equipment. Use of sedation or anesthesia decreases worker exposure to ionizing radiation.

Endotoxin and dust at respirable and nonrespirable particle sizes are not consistent between cage- and floor-housed poultry operations.

BACKGROUND: Individuals engaged in work in intensive animal houses experience some of the highest rates of occupationally related respiratory symptoms. Organic dust and in particular endotoxin has been most closely associated with respiratory symptoms and lung function changes in workers. It has previously been shown that for intensive poultry operations, type of poultry housing [cage-housed (CH) versus floor-housed (FH)] can influence the levels of environmental contaminants. The goal of the study was to determine the differences in endotoxin and dust levels at different size fractions between CH and FH poultry operations. METHODS: Fifteen CH and 15 FH poultry operations were sampled for stationary measurements (area) of dust and associated endotoxin. Fractioned samples were collected utilizing Marple cascade impactors. Gravimetric and endotoxin analysis were conducted on each of the filters. RESULTS: When assessed by individual Marple stage, there was significantly greater airborne endotoxin concentration (endotoxin units per cubic meter) in the size fraction >9.8 µm for the FH operations whereas at the size fraction 1.6-3.5 µm, the CH operations had significantly greater airborne endotoxin concentration than the FH operations. Endotoxin concentration in the dust mass (endotoxin units per milligram) was significantly greater in the CH operations as compared to the FH operations for all size fractions >1.6 µm. As such, endotoxin in the respirable fraction accounted for 24% of the total endotoxin in the CH operations whereas it accounted for only 11% in the FH operations. There was significantly more dust in all size fractions in the FH operations as compared to the CH poultry operations. CONCLUSIONS: There is more endotoxin in the presence of significantly lower dust levels in the respirable particle size fractions in CH poultry operations as compared to the FH poultry operations. This difference in respirable endotoxin may be important in relation to the differential respiratory response experienced by CH and FH poultry operation workers.