var r={
  'special':/[\W]/g,
  'quotes':/['\''&'\"']/g,
  'notnumbers':/[^\d]/g
}

function valid(o,w){
  o.value = o.value.replace(r[w],'');
}

function valid2(o,w){
  o.value = o.value.replace(r[w],'');
  if (o.value < "10" ) then 
 document.pesq.chq1.value ="";  
 document.pesq.chq2.value =""; 
 document.pesq.chq3.value =""; 
 document.pesq.chq4.value =""; 
}