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The SARS-CoV-2 pandemic led to an unprecedented demand for PPE and generated a small-scale industry making personalised face coverings. Concerns had been raised about the use of natural rubber latex (NRL) as an elastomeric material, with its health risks. We have investigated the levels of four NRL allergens and total protein in elastomeric ear-straps in manufactured face coverings and the material sold for their production, and a number of imported N95/KN95 PPE masks. None of the samples identified whether NRL was involved or not. NRL allergens levels in manufactured masks were low or not detectable; 3/10 of the N95/KN95 masks showed levels above the limit of detection, probably reflecting low-level cross-contamination during manufacture. Three batches of material sold for “the manufacture of ear straps for face coverings” had significant but variable levels of allergen (250–2526 ng/g of material). Historically, extractable protein measurements have been used as an indicator of possible NRL proteins. This study showed significant levels of apparent protein in sample extracts without measurable NRL allergens or confirmation by electrophoresis. Therefore, the immunochemical measurement of NRL allergens remains key to rule out elastomeric material with the potential to cause latex-related health problems.

Normal practice in continuous digester operation is to set the production rate through the chip meter speed. This speed is seldom, if ever, adjusted except to change production, and most of the other digester inputs are ratioed to it. The inherent assumption is that constant chip meter speed equates to constant dry mass flow of chips. This is seldom, if ever, true. As a result, the actual production rate, effective alkali (EA)-to-wood and liquor-to-wood ratios may vary substantially from assumed values. This increases process variability and decreases profits. In this report, a new continuous digester production rate control strategy is developed that addresses this shortcoming. A new noncontacting near infrared–based chip moisture sensor is combined with the existing weightometer signal to estimate the actual dry chip mass feedrate entering the digester. The estimated feedrate is then used to implement a novel feedback control strategy that adjusts the chip meter speed to maintain the dry chip feedrate at the target value. The report details the results of applying the new measurements and control strategy to a dual vessel continuous digester.

To establish the relationship between quantitative tests of hand function and upper limb disability, as measured by the Disability of the Arm, Shoulder and Hand (DASH) questionnaire, in hand-arm vibration syndrome (HAVS).A total of 228 individuals with HAVS were included in this study. Each had undergone a full HAVS assessment by an experienced physician, including quantitative tests of vibrotactile and thermal perception thresholds, maximal hand-grip strength (HG) and the Purdue pegboard (PP) test. Individuals were also asked to complete a DASH questionnaire.PP and HG of the quantitative tests gave the best and statistically significant individual correlations with the DASH disability score (r2 = 0.168 and 0.096). Stepwise linear regression analysis revealed that only PP and HG measurements were statistically significant predictors of upper limb disability (r2 = 0.178). Overall a combination of the PP and HG measurements, rather than each alone, gave slightly better discrimination, although not statistically significant, between normal and abnormal DASH scores with a sensitivity of 73.1% and specificity of 64.3%.Measurements of manual dexterity and hand-grip strength using PP and HG may be useful in helping to confirm lack of upper limb function and 'perceived' disability in HAVS.

BACKGROUND Staging hand-arm vibration syndrome (HAVS) depends upon accurate reporting of the extent and frequency of blanching attacks. Reporting may not be repeatable and not all individuals classifiable using the Stockholm Workshop Scale (SWS). For Department of Trade and Industry (Dti) coal miners' assessments, the SWS was modified to include a blanching score. Further modifications, which involve splitting Stage 2V into 'early' and 'late' have been proposed but the impact of this on classification has not been investigated. AIM To investigate the impact of modifications in the SWS on HAVS classification. METHODS Staging of individuals with HAVS according to the SWS using two modified scales. Two different cut-offs for defining 'frequent' blanching attacks (>or=3 or >or=7 attacks/week, respectively) were used. RESULTS One hundred and sixty-five individuals were staged. Using the SWS, 58 and 31% of the population were unclassifiable using the two cut-offs, respectively. The modification splitting Stage 2V reduced the proportions that were unclassifiable to 2 and 9%, respectively, and increased those classified as Stage 2V. The cut-off for frequent attacks used (3 or 7) affected the proportion of individuals falling into the subdivisions of Stage 2 with 17 and 42% being classified as 2Vearly and 45 and 20% as 2Vlate, respectively. CONCLUSIONS Subdividing Stage 2V enables more individuals to be classified, but the proportion falling into each category is susceptible to the cut-off used for defining frequent attacks. Caution may need to be applied if this categorization is used to make decisions regarding fitness to work.

This paper describes a routine, robust, and reproducible liquid chromatography-inductively coupled plasma-mass spectrometry (LC-ICP-MS) speciation method for five arsenic compounds [arsenobetaine (AB), arsenite, arsenate, monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA)] in urine. Concentrations of these arsenic species in urine samples are reported in two sets of non-occupationally exposed controls with one set having consumed fish within 24 h (n = 31) and the other not having consumed fish for 48 h (n = 34). Arsenic species in urine samples from workers in both the timber treatment industry (n = 49) and semiconductor industry (n = 46) are also reported. The arsenic content in all of the samples was also determined using hydride-generation coupled with ICP-MS. The results show that urine samples from people not occupationally exposed to arsenic contain low levels of DMA, MMA, and AB and that only urine from smokers contained any inorganic arsenic. Consumption of seafood was seen to significantly increase the levels of AB and DMA in the unexposed persons. Urine samples from the semiconductor workers exhibited significantly higher levels of arsenite, arsenate, and DMA than the unexposed samples. The urine samples from timber treatment workers exhibited significantly higher levels of four arsenic species (not AB) than those observed in both the control groups and the semi-conductor workers.

To investigate whether hand-arm vibration syndrome (HAVS) leads to disability in the upper extremity or deficit in quality of life (QoL) using validated questionnaire tools, and to establish whether these effects are related to the Stockholm Workshop Staging (SWS).This was a postal cross-sectional questionnaire study with a 50% response rate. Four hundred and forty-four males, who had been diagnosed and staged according to the SWS were sent the Disability in the Arm, Shoulder and Hand (DASH) and the SF-36v2 QoL questionnaires.HAVS cases had significantly greater DASH disability scores and reduced QoL physical and mental component scores compared to published normal values. Those HAVS cases with a presumptive diagnosis of Carpal Tunnel Syndrome(CTS) had even higher disability scores. There was a clear, linear relationship between both the DASH disability score and the physical component of the QoL and sensorineural SWS, but not with the vascular SWS.HAVS has a significant effect on an individual's perceived ability to perform everyday tasks involving the upper extremity, and their quality of life. Physical capability may be further compromised in those individuals who have a presumptive diagnosis of CTS. These findings may have important implications regarding management of the affected worker.

Hand-arm vibration syndrome (HAVS) is a complex condition with vascular, sensorineural and musculoskeletal components. A number of quantitative tests have been used for assisting in the diagnosis of HAVS and grading disease severity.To investigate and compare the diagnostic value of finger systolic blood pressure (FSBP) and rewarming of finger skin temperature (FST) following cold-provocation testing, in the assessment of vascular HAVS.Twenty-four individuals with vascular HAVS (Stockholm Workshop stage 2 or 3V) and 22 control subjects underwent FSBP measurements at 30, 15 and 10 degrees C and monitoring of FST following immersion of the hands in water at 15 degrees C for 5 min.There was a significant reduction in median FSBP% in the vascular HAVS group in the change in FSBP from 30 to 15 degrees C adjusted for brachial blood pressure (FSBPC%). There was no difference in the median time for FST to rewarm by 4 degrees C between HAVS cases and controls. The sensitivity and specificity of FSBP to discriminate between the groups varied between 44 and 61% and 91 and 95%, respectively. The sensitivity and specificity for the time for FST to rewarm by 4 degrees C were 71 and 77%.There is little evidence that the described form of finger rewarming after cold-provocation testing is a useful diagnostic test for vascular HAVS, although it may have some moderate influence in ruling out vascular problems. Based on our data, the FSBP may also have limited use in confirming a positive diagnosis of vibration-induced vascular problems. The higher specificity of the FSBP test suggests it may have some value in ruling out the vascular component of HAVS. The data from this study do not confirm the diagnostic power of FSBP for the vascular component of HAVS reported by a few other investigators.

Background - Accurate diagnosis and staging of hand-arm vibration syndrome (HAVS) is important in health surveillance of vibration-exposed workers and the substantial number of related medico-legal cases. The measurement of the rewarming rate of fingers after cold provocation to the hands (CPT) has been suggested as a useful test in diagnosing HAVS. Aim - To investigate the diagnostic value of a standardized version of the CPT test using a 15 degrees C cold challenge for 5 min applied in the recent compensation assessment of UK miners. Methods - Analysis of a subset of UK miners assessed at our unit, together with data from a small repeatability study of the standardized CPT in normal subjects. Results - Rewarming time in the CPT was significantly lower in those subjects classified as vascular Stockholm stage 0 compared with Stockholm stages 1-3 combined, but did not discriminate between the stages of abnormality. Using the suggested cut-off in the CPT test, the sensitivity and specificity were calculated as 43 and 78%, respectively. Receiver operator characteristic analysis suggested that the rewarming time of highest accuracy gave a sensitivity of 66% and specificity of 59%. In 10 miners who reported unilateral hand blanching, there was no significant difference in CPT measurements between blanching and non-blanching hands. Repeat CPT measurements in normal subjects suggested mean differences of 52 and 107 s for each hand, and the Bland-Altman coefficient of repeatability was approximately 600 s for all fingers. Conclusion - Single application of this standardized CPT test may have limited value in diagnosing the vascular component of HAVS in an individual.

Soya is an important worldwide agricultural product widely shipped and imported in bulk. It contains a number of recognised allergens and the use of soya products and its dockside unloading have been associated with occupational asthma and community episodes of asthma. Two recognised inhalation soya allergens, soya trypsin inhibitor (STI) and hydrophobic soya protein (HSP), were measured in personal and static air samples collected at a United Kingdom (UK) dock during 3 days of unloading three bulks of processed soya beans and soya pelletised husk. Static samples included task-related and those taken at the workplace perimeter and neighbouring sites. Soluble total protein (STP) and gravimetric dust analyses were also undertaken. While gravimetric dust results in personal air samples were below half of the current UK exposure limit of 10 mg m-3 for grain dust, and generally less than 0.5 mg m-3 for the static samples, airborne concentrations for STI and HSP ranged between 0-3,071 and 11-12,629 ng m-3, respectively, while the correlation between the two specific allergen measurements was generally good (Rank Spearman coefficient 0.74). The data from this investigation suggest that HSP is a more sensitive indicator of soya exposure than STI, but only for soya husk, while STI may be equipotent in detecting exposure to both hull and bean derived soya products. Both assays appear sensitive techniques for investigating the control of exposure to allergenic soy material. The endotoxin level in the husk bulk was 15-60-fold that found in the two chipped bean bulks., Soja je gotovo u cijelome svijetu važan poljoprivredni proizvod, pa se prevozi često i u velikim količinama. Sadrži mnoštvo poznatih alergena, a korištenje proizvoda od soje i rukovanje njima prilikom iskrcavanja robe povezivani su s pojavama profesionalne astme. Razine dvaju inhalacijskih alergena, soja tripsin inhibitora (STI) i hidrofobnog proteina sojina zrna (HSP), mjerene su u uzorcima zraka prikupljenim osobnim uzorkovačem i stacionarnim uzorkovačima u jednom britanskom lučkom doku tijekom 3 dana iskrcavanja triju pošiljaka prerađena sojina zrna i kuglica sojine mahune. Također je provedena analiza ukupnih topivih proteina i gravimetrijska analiza prašine. Rezultati gravimetrijske analize uzoraka prikupljenih osobnim uzorkovačem bili su dobrano ispod polovice trenutačne granice izloženosti u Velikoj Britaniji (10 mg m-3 za prašinu sjemena) i općenito ispod 0,5 mg m-3 kod statičnih uzoraka, a razine STI-a i HSP-a u zraku prikupljenom stacionarnim uzorkovačem bile su unutar raspona 0-3.071, odnosno 11-12.629 ng m-3. Korelacija između ta dva alergena bila je dobra (Rank Spearmanov koeficijent 0,74). Rezultati ovoga istraživanja pokazali su da je HSP precizniji pokazatelj izloženosti soji od STI-a, no samo za sojine mahune; STI bi mogao biti precizniji pokazatelj u pogledu proizvoda od sojine ljuske ili zrna. Obje su se vrijednosti pokazale preciznim tehnikama za praćenje izloženosti sojinim alergenima. Razina endotoksina u pošiljci sojinih mahuna bila je 15 do 60 puta veća od one u dvjema pošiljkama usitnjenog zrna.

Soya is an important worldwide agricultural product widely shipped and imported in bulk. It contains a number of recognised allergens and the use of soya products and its dockside unloading have been associated with occupational asthma and community episodes of asthma. Two recognised inhalation soya allergens, soya trypsin inhibitor (STI) and hydrophobic soya protein (HSP), were measured in personal and static air samples collected at a United Kingdom (UK) dock during 3 days of unloading three bulks of processed soya beans and soya pelletised husk. Static samples included task-related and those taken at the workplace perimeter and neighbouring sites. Soluble total protein (STP) and gravimetric dust analyses were also undertaken. While gravimetric dust results in personal air samples were below half of the current UK exposure limit of 10 mg m(-3) for grain dust, and generally less than 0.5 mg m(-3) for the static samples, airborne concentrations for STI and HSP ranged between 0-3,071 and 11-12,629 ng m(-3), respectively, while the correlation between the two specific allergen measurements was generally good (Rank Spearman coefficient 0.74). The data from this investigation suggest that HSP is a more sensitive indicator of soya exposure than STI, but only for soya husk, while STI may be equipotent in detecting exposure to both hull and bean derived soya products. Both assays appear sensitive techniques for investigating the control of exposure to allergenic soy material. The endotoxin level in the husk bulk was 15-60-fold that found in the two chipped bean bulks.

Anaerobic toxicity assays and biochemical methane potential studies were performed on three waste streams (acrylic acid, ethylene oxide and total wastes) from a petrochemical facility. The acrylic waste contained high concentrations (> 350 mg l−1) of acetic acid, acrylic acid, formaldehyde and benzaldehyde and low concentrations ( 950 mg l−1) of ethylene glycol, formaldehyde and acetaldehyde and low concentrations (< 50 mg l−1) of other compounds. The total waste was the combination of all waste streams generated at the plant. Unacclimated anaerobic glucose-acetate enrichment culture and a culture acclimated to the acrylic waste were used. The oxide waste with total organic carbon (TOC) concentrations of about 1400 mg l−1 was found to be readily degradable even without an acclimation period. The total waste showed no inhibition to the unacclimated glucose-acetate culture at a TOC concentration of about 250 mg l−1; however, the culture was inhibited at a TOC concentration of about 450 mg l−1. The acrylic waste caused inhibition at a TOC concentration of 269 mg l−1 in the unacclimated culture. An acclimated culture degraded a TOC concentration of 223 mg l−1 of the acrylic acid stream but was inhibited by a concentration of 643 mg l−1. A reduced acrylic waste load with a significant portion of the acetic acid removed was degradable at a TOC concentration of 138 mg l−1.

Preliminary study for a group of perspective reconstruction drawings of the exterior of Durham Cathedral has led to a reappraisal of the original design and of its progress towards completion. The west towers may be fifty or more years earlier than the generally accepted date of c. 1200, preceding the Galilee chapel. The paired eastern towers strongly suggest links with the ‘imperial’ churches of the Rhineland, and are not readily paralleled in Normandy. Some English churches with eastern towers are listed, indicating that they were not especially rare.Durham was built on the largest scale to house the body and shrine of St Cuthbert. It was an avant-garde showpiece indicating the wealth and importance of its bishop and monastic community at both English and European levels.

Exposure to hand-transmitted vibration is usually assessed according to International Standard ISO 5349-1:2001 using the frequency weighting W(h). This paper compares eight frequency weightings that might be used to supplement or replace W(h). The comparison is based on a data from two databases, one containing over 7200 measured hand-arm vibration (HAV) spectra from a wide range of industrial machines the other recording exposure history and injury for workers referred to the Health and Safety Laboratory. Acceleration spectra from the machinery database are analysed to give weighted values for the alternative frequency weightings. These weighted values are compared and then used to estimate a set of alternative lifetime vibration dose values for subjects in the referral database. Statistical comparison of these lifetime dose values against assessments of hand-arm vibration syndrome (HAVS) and sensorineural HAVS prevalence suggests that values based the two weightings W(h) and W(h50lp) (the W(h) weighing low-pass filtered at 50 Hz) provide the strongest indicators for developing these injuries. For vascular HAVS there was no clear evidence to advocate any individual frequency weighting. For all injury categories the strongest relationships were for the first power of acceleration magnitude.

The aim was to investigate whether the use of infra-red thermography (I-R) and measurement of temperature gradients along the finger could improve the diagnostic accuracy of cold-provocation testing (15 degrees C for 5 min) in vascular hand-arm vibration syndrome (HAVS). Twenty-one controls and 33 individuals with stages 2/3V HAVS were studied. The standard measurement of time to rewarm by 4 degrees C (T4 degrees C) and temperature gradients between the finger tip, base and middle (measured using I-R) were calculated. Receiver Operating Characteristics (ROC) analysis to distinguish between the two groups revealed that for T4 degrees C the area under the ROC curve was not statistically significantly different from 0.5 (0.64 95% confidence interval 0.49-0.76). The difference between the tip and middle portion of the finger during the sixth minute of recovery was the most promising gradient with an area of 0.76 (95% confidence interval 0.62-0.87), and sensitivity and specificity of 57.6% and 85.7% respectively. However, this was not significantly different from that for the time to rewarm by 4 degrees C. In conclusion, the cold-provocation test used in this study does not appear to discriminate between individuals with stage 2/3V HAVS and controls and this is not improved by the measurement of temperature gradients along the fingers using I-R.

The team of TIAX LLC, ExxonMobil Research and Engineering Company, and Callidus Technologies, LLC conducted a six-year program to develop an ultra-low emission process heater burner and an advanced high efficiency heater design. This project addresses the critical need of process heater operators for reliable, economical emission reduction technologies to comply with stringent emission regulations, and for heater design alternatives that reduce process heater energy requirements without significant cost increase. The key project targets were NOx emissions of 10 ppm (@ 3% O2), and a heater thermal efficiency of 95 percent. The ultra low NOx burner was developed through a series of pilot-scale and field tests combined with computational fluid dynamic modeling to arrive at simultaneous low emissions and suitable flame shape and stability. Pilot scale tests were run at TIAX, at the 2 MMBtu/hr scale, and at Callidus at 8 MMBtu/hr. The full scale burner was installed on a 14 burner atmospheric pipestill furnace at an ExxonMobil refinery. A variety of burner configurations, gas tips and flame stabilizers were tested to determine the lowest emissions with acceptable flame shape and stability. The resulting NOx emissions were 22 ppm on average. Starting in 2001, Callidus commercialized the original ultra lowmore » NOx burner and made subsequent design improvements in a series of commercial burners evolving from the original concept and/or development. Emissions in the field with the ultra low-NOx burner over a broad spectrum of heater applications have varied from 5 ppm to 30 ppm depending on heater geometry, heater service, fuel and firing capacity. To date, 1550 of the original burners, and 2500 of subsequent generation burners have been sold by Callidus. The advanced heater design was developed by parametric evaluations of a variety of furnace and combustion air preheater configurations and technologies for enhancing convective and radiative heat transfer. The design evolution relied heavily on computational fluid dynamic predictions of design alternatives. The final design features modular separate radiant cells, each with one and two-side fired vertical tubes. The convection section configuration is vertical tube banks enclosed in the radiant channels. Commercial modular plate air preheaters are used. The predicted performance for the integrated advanced heater and Callidus burner is 95 percent efficiency with 9 ppm NOx emissions firing natural gas, and 12 ppm firing refinery gas. The total erected cost is less than a conventional heater with combustion air preheat.« less

BACKGROUND Renovation of windows in old houses has recently established itself as an industry. A recognizable occupational lead exposure exists, which has not been studied previously. AIM To compare lead exposure amongst window renovators with other groups of lead-exposed workers. METHODS Using blood lead results measured at the Health and Safety Laboratory (HSL), Sheffield, comparisons were made between three cohorts: window renovation workers, all male workers monitored by HSL during the period 1999-2001 and 63 male subjects involved in chemical paint-stripping of wood. RESULTS Both the window renovation and the wood-stripping cohorts show significantly higher blood lead distributions than the 'all workers' cohort (P < 0.001). A similar pattern was also found for comparison of the prevalence of subjects above the UK suspension level of 60 microg/dl (2.89 microM) (window renovation, P < 0.001; wood-stripping, P < 0.0001). Blood lead results at or above the suspension level in wood-strippers were significantly higher compared to window renovators (P = 0.034). CONCLUSION Window renovation is shown to present a potential for significant lead exposure, and suspension from work under The Control of Lead at Work Regulations 2002. Two groups of risk factors predominate: the well-documented potential for release of lead from old paint, and the peripatetic nature of the work.

Hand-arm vibration syndrome (HAVS) consists of vascular, neurosensory and musculoskeletal components, characterized by symptoms that include Raynaud's phenomenon, tingling and numbness in the hands. However, there has been little published data on the effects of HAVS on the capability to carry out normal daily tasks. We have investigated the application of the widely-used disability, arm, shoulder and hand (DASH) disability questionnaire that reflects functionality problems in the upper extremities, as well as symptoms, in a HAVS cohort.The cohort consisted of 118 males who, as a part of their health surveillance, had been referred for further assessment and Stockholm workshop staging. This process involved medical interview, physical examination and quantitative tests covering neurosensory function, manual dexterity and handgrip strength.The relationship between DASH outcome metric and a combination of quantitative tests reflecting a range of abnormalities found in HAVS, supports the validity of this questionnaire in HAVS studies. The data suggest that HAVS cases have a greater level of upper extremity disability compared with a general population. The study confirms that disability in HAVS is very largely related to sensorineural Stockholm workshop staging, rather than vascular staging. Any influence of vibration-induced Raynaud's phenomenon on upper extremity disability is related to the frequency of blanching attacks rather than their extent across the digits.This study strengthens the importance of identifying and preventing the exacerbation of the neurosenory component of HAVS, that unlike the blanching attacks of the vascular component does not have such an obvious pathognomic signal.

Aim To define the diagnostic power of simple questions most applicable for a hand-arm vibration syndrome (HAVS) assessment screening questionnaire. Method Using a binary logistic regression we analysed 365 physician led HAVS health surveillance assessments to identify which questions could form the basis of a screening questionnaire. Results Four sensorineural related questions regarding tingling and numbness in response to the cold and after using vibrating tools, and two vascular-related questions focusing on the patient's fingers going white on exposure to cold and numbness during an attack of whiteness were identified. Conclusions Questions of high sensitivity for screening subjects for the vascular and neurosensory components of HAVS were identified, which can be used to identify those requiring further clinical investigation and functional testing.

We used urinary assays as a non-invasive method to examine corticosterone levels in two outbred strains of male laboratory mice (BKW and CD-1). Measures were taken before and after 2 weeks of pair housing, to examine the effects of social stress. We found that CD-1 mice had significantly higher corticosterone levels compared to BKW mice both before and after pairing. Behavioural measures provided evidence that, when paired, both strains of mice polarised into dominants and subordinates, with a higher overall incidence of aggressive acts in the BKW mice. Some pairings had to be separated to prevent injuries so the pairing procedure introduced a selection for non-aggressive socially tolerant mice. Social status was nevertheless found to be associated with pre-existing differences in urinary corticosterone in the CD-1 strain: mice that later became dominant had overall lower levels of urinary corticosterone compared to subordinates. In conclusion, urinary corticosterone levels indicated clear differences in physiology, likely to be related to the adrenal stress response, dependent on both strain and social status. Thus, this non-invasive measure could help to predict the welfare outcomes of social housing and how these may depend on dominance status, rather than overall levels of aggression, in different strains of mice.